Pre-Conference CubeSat Developers’ Workshop
Technical Chair Jordi Puig-Suari
Session I: Beyond Leo
9:30 AM
BioSentinel: A 6U Nanosatellite for Deep Space Biological Science
Hugo Sanchez, James Chartres, Robert Hanel, Sharmila Bhattacharya, Antonio Ricco, Matthew Dortenzio
NASA Ames Research Center
ABSTRACT
BioSentinel is a "6U" (10 x 22 x 34 cm; 14 kg) nanosatellite flying as a secondary payload aboard NASA's
Space Launch System (SLS) Exploration Mission (EM) 1, scheduled for launch in 2018. BioSentinel
measures the damage and repair of DNA in a biological organism and compares that to information to
onboard physical radiation sensors. In order to understand the relative contributions of the space
environment's two dominant biological perturbations, reduced gravity and ionizing radiation, results
from deep space will be compared to data obtained in LEO (on ISS) and a ground control on Earth. These
data points allow the validation of existing biological radiation damage and repair models, and for
extrapolation to humans, to assist in mitigating risks during future long-term exploration missions
beyond LEO.
In addition to providing the first biological results from beyond LEO in over 4 decades, BioSentinel will
provide an adaptable small-satellite instrument platform to perform a range of human-explorationrelevant measurements that characterize the biological consequences of multiple outer space
environments. BioSentinel is being developed at NASA Ames Research Center and funded by NASA's
Advanced Exploration Systems program.
The spacecraft operates in a deep space environment (heliocentric orbit) with functions that include
command and data handling, communications, power generation (via deployable solar panels) and
storage, and attitude determination-and-control system with micropropulsion. The BioSentinel
spacecraft advances multiple nanosatellite systems in order to function beyond LEO:
* Biofluidics managing long term (12 - 18 months) biological stasis and modular integrated sample
instrumentation
* Biological measurement of solar particle events and the radiation environment beyond Earth orbit
* Close integration of living biological radiation event monitors with miniature physical radiation
spectrometers
* Shielding-, hardening-, design-, and software-derived radiation tolerance for electronics
* Communications from distances of ≥ 500,000 km
* Autonomous attitude control, momentum management, and safe mode of nanosatellites in deep
space
* Reliable functionality for 12 - 18 months of key subsystems
* Thermal control capable of maintain a biological payload
BioSentinel is approaching the Critical Design Review (CDR) with initial subsystems approaching
completion or undergoing testing. Integration and testing of multiple subsystems are beginning. The
mission concept of operations and fault management plan address mode transitions and fault recovery
with limited ground communication. The BioSensor has been operating in a lab environment and the
modular integrated detectors have undergone radiation testing with biological samples showing
promising results for filling a strategic knowledge gaps in radiation effects on biology.
9:45 AM
Near Earth Asteroid (NEA) Scout Solar Sail Implementation
Jared Dervan - NASA Marshall Space Flight Center; Corydon Loomis, Travis Imken - Jet Propulsion
Laboratory, California Institute of Technology; Tiffany Lockett, Naeem Ahmad, Andrew Heaton - NASA
Marshall Space Flight Center; Damon Landau - Jet Propulsion Laboratory, California Institute of
Technology
ABSTRACT
The Near Earth Asteroid (NEA) Scout mission is an innovative CubeSat concept manifested on Space
Launch System (SLS) Exploration Mission 1 (EM-1), the first planned flight of the SLS and second uncrewed test flight of the Orion Multi-Purpose Crew Vehicle. This paper will focus on mission elements
involved in the implementation of a solar sail on a deep space CubeSat mission and will leverage
component and subsystem test and analysis results. Spacecraft configuration dependencies and
constraints will be addressed including the manipulation of the spacecraft center-of-mass and center-ofpressure relationship through a new enabling technology, the Active Mass Translator (AMT). Prediction
of the resulting propulsive solar sail characteristics through thrust model development and associated
impacts on mission design and trajectory resiliency will also be included. Subsequent to these inputs,
imposed power and telecommunication constraints and overall impacts on the mission ConOps will be
outlined. Breadboard and engineering development unit test results will be presented in the context of
these system-level dependencies to provide developmental lessons learned and address competing
spacecraft needs.
The "6U" solar sail-propelled CubeSat will address human exploration-focused Strategic Knowledge
Gaps. NEA Scout will perform a close and slow rendezvous to provide the first imagery and
characterization of a NEA in the <100m range. The CubeSat will utilize an 86 m² solar sail to serve as the
primary means of propulsion to the NEA providing a ΔV up to two kilometers per second, a magnitude
currently impossible to meet with other high technology readiness level CubeSat-sized propulsion
systems. Momentum exchange between the Sun's photons and the solar sail membrane provides the
means necessary to perform a long duration deep space cruise and perform a NEA rendezvous at <1 AU
distance from Earth. The mission combines synergies across multiple fields (resource utilization,
planetary defense, human operations, and science) and paves the way for future multi-spacecraft
exploration of NEAs. Using an optical imaging payload, NEA Scout will characterize the morphology,
rotational and orbital properties, volume, color type and meteoritic classification, as well as the
dust/debris environment of the target.
NEA Scout is funded through NASA's Human Exploration and Operations Mission Directorate's Advanced
Exploration Systems program and is under joint development by the Marshall Space Flight Center
(MSFC) and Jet Propulsion Laboratory (JPL). The missions leverage technologies and experience gained
from JPL's deep-space CubeSat developments (Interplanetary Nano-Spacecraft Pathfinder In Relevant
Environment (INSPIRE) and Mars Cube One (MarCO)) and MSFC's NanoSail-D2, the first CubeSat mission
to deploy a solar sail.
10:00 AM
A Europa CubeSat Concept Study for Measuring Europa's Atmosphere
Nancy Chanover, James Murphy, Kyle Rankin, Steven Stochaj, Alexander Thelen - New Mexico State
University
ABSTRACT
This presentation is the product of a nine-month mission concept study for a CubeSat that would be
carried aboard the JPL Europa Multiple-Flyby Mission, released in the Jovian system and make
measurements at Europa. We examined the scientific return as well as the technical feasibility of a
CubeSat designed to study the linkage between Europa's radiation environment which generates
Europa's atmosphere through sputtering and radiolytic processes, and its atmospheric structure. This
would be accomplished by measuring a) energetic particles at Europa and b) its atmospheric density
through drag forces on the CubeSat. The findings of our concept study for the Deployable Atmospheric
Reconnaissance CubeSat with Sputtering Ion Detector at Europa (DARCSIDE) indicate that the
technology exists to enable a 3U, 4.4 kg CubeSat to detect Europa's tenuous atmosphere beginning ~200
km above the surface for ~400 s of flight time during a single flyby, by measuring drag on the vehicle. By
including a charged particle detector, we can also measure the sputtering-induced charged particle flux
incident on Europa's surface - either for a single arc across the surface or for a number of predeployment Jovian orbits while onboard the Europa Multiple-Flyby Mission - depending on the length of
time the instrument is powered on. In addition to providing highly complementary science to the Europa
Multiple-Flyby Mission, the combination of the accelerometer and charged particle detector will yield
important insights for the study of Europa's atmosphere and surface composition, its interaction with
the Jovian magnetosphere, and possibly links to its subsurface ocean.
This presentation will be focused on the technical challenges of the DARCSIDE mission. The major
challenges to be discussed will include how to survive with only one twenty-fifth the energy available at
the Earth, this has significant implications for spacecraft temperature and electrical power generation.
Additionally, survival in the extreme Jovian radiation environment will be discussed, along how to meet
planetary protection requirements for Europa, which requires DARCSIDE to never impact Europa. Finally,
the design for the DARCSIDE drag system, and accelerometers will be discussed.
10:15AM
The Lunar Polar Hydrogen Mapper (LunaH-Map) CubeSat Mission
Hannah Kerner, Craig Hardgrove, Jim Bell, Robert Amzler – Arizona State University; Alessandra Babuscia
- Jet Propulsion Laboratory, California Institute of Technology; Matthew Beasley - Planetary Resources;
Zach Burnham, Kar-Ming Cheung - Jet Propulsion Laboratory, California Institute of Technology
ABSTRACT
The Lunar Polar Hydrogen Mapper (LunaH-Map) is a 6U CubeSat mission recently selected by NASA's
Science Mission Directorate to fly as a secondary payload on first Exploration Mission (EM-1) of the
Space Launch System (SLS), scheduled to launch in July 2018. LunaH-Map is led by a small team of
researchers and students at Arizona State University, in collaboration with NASA centers, JPL,
universities, and commercial space businesses. The LunaH-Map mission will reveal hydrogen
abundances at spatial scales below 10 km in order to understand the relationship between hydrogen
and permanently shadowed regions, particularly craters, at the Moon's South Pole. The mission's
primary payload is designed to use the scintillator material Cs2YLiCl6:Ce, or "CLYC" to measure count
rates of thermal and epithermal neutrons. Enabled by a low-thrust ion propulsion system, LunaH-Map
will achieve lunar orbit insertion within ~12 months of SLS separation and maneuver into a highly
elliptical, low-perilune (5-10 km) orbit centered around the South Pole of the Moon. In this orbit, LunaHMap will achieve over 140 low-altitude fly-bys of the South Pole during its two month science phase.
LunaH-Map and two fellow secondary payloads selected by NASA to fly on SLS EM-1 will be the first
CubeSats to explore the Moon and interplanetary space.
Session II: C&DH
11:00 AM
NASA Operational Simulator for Small Satellites (NOS3): Tools for Software-based Validation and
Verification of Small Satellites
Matthew Grubb, Justin Morris, Scott Zemerick NASA, John Lucas - NASA IV&V
ABSTRACT
The NASA Operational Simulator for Small Satellites (NOS3) is a suite of software tools to aid in areas
such as software development, integration & test (I&T), mission operations/training, verification and
validation (V&V), and software systems check-out. NOS3 provides a software development
environment, a multi-target build system, operational interface/ground software, dynamics and
environment simulations, and software-based hardware models. NOS3 enables the development of
flight software (FSW) early in the project life cycle when hardware availability is limited. Small satellite
development suffers from extensive lead times on many of the commercial-off-the-shelf (COTS)
components as well as limited funding for engineering test units (ETUs). To alleviate the need to provide
a hardware test-bed for each developer/tester, NOS3 hardware models are based upon characteristic
data or manufacturer's data sheets for each individual component. The NOS3 hardware models' fidelity
is such that FSW executes unaware that physical hardware is absent. This allows FSW binaries to be
compiled for both the simulation environment and the flight computer without changing the FSW
source code. For hardware models that provide data which is dependent upon the environment and
spacecraft dynamics, such as a GPS receiver or magnetometer, an open-source tool from NASA GSFC (42
Spacecraft Simulator) is used to provide the necessary data. The underlying infrastructure used to
transfer messages between FSW and the hardware models can also be used to monitor, intercept, and
inject messages, which has proven to be beneficial for V&V of larger missions such as James Webb Space
Telescope (JWST). As hardware is selected and becomes available, drivers can be added to the NOS3
environment to enable hardware-in-the-loop (HWIL) testing. When strict time synchronization is not
vital, any number of combinations of hardware components and software-based models can be tested.
The NOS3 operator interface is the open-source COSMOS User Interface for Command and Control of
Embedded Systems, developed by Ball Aerospace. For testing FSW, plug-ins are implemented in
COSMOS to control the NOS3 simulations, while the command and telemetry tools available in COSMOS
are used to communicate with the FSW. NOS3 is actively being used for FSW development and
component testing of the Simulation-to-Flight 1 (STF-1) CubeSat. As NOS3 matures, hardware models
have been added for common small satellite components such as NovAtel GPS receivers, Clyde Space
electrical power systems and batteries, and Innovative Solutions in Space antenna systems. In the
future, NASA IV&V plans to distribute NOS3 to other small satellite developers and release the suite to
the open-source community.
11:15 AM
Multi-algorithmic Hybrid Attitude Determination and Control System of the CubeSat "CADRE"
Dae Young Lee, Prince Kuevor, James Cutler - University of Michigan
ABSTRACT
The CubeSat investigating Atmospheric Density Response to Extreme driving (CADRE), developed by the
Michigan eXploration Laboratory, carries the Wind Ion Neutral Composition Suite (WINCS). WINCS
monitors the response of Earth's upper atmosphere to auroral energy inputs and requires a specific
attitude within 1 degree of pointing accuracy.
To satisfy the required pointing accuracy, multiple estimation and control algorithms are required in the
attitude determination and control system (ADCS). For instance, if a satellite adopts a reaction wheel
assembly (RWA) as its main control actuator, an additional sub-control algorithm and actuator set is
required for desaturation of the reaction wheels. If the sub-algorithm is not managed properly, its usage
could reduce the pointing accuracy established by the main control algorithm due to the conflicting
objectives. Additionally, when an Extended Kalman Filter (EKF) is used for on-orbit attitude
determination, a primitive estimation algorithm, such as quaternion estimation (QUEST), must be used
prior to activating the EKF to reduce the initial estimation error. For such a system, the switching
condition from the primitive algorithm to the EKF is critical as it can determine the performance of the
filter on estimation accuracy. In order to manage the potential conflicts and switching conditions that
occur in implementing multiple estimation and control algorithms, an active ADCS can benefit from
adopting a hybrid system concept which is based on a finite-state machine. Dennis et al[1]. showed the
effectiveness of applying a hybrid system to single and multiple satellites capable of performing orbit
corrections.
To analyze the performance of the hybrid estimation and control algorithms, a hardware-in-the-loop
simulation (HILS) with a 3D hemispherical air bearing was developed and tested against the results of
mathematical simulations. To facilitate the HILS, and as part of the operations of CADRE, an ADCS
middleware was developed based on a real-time operating system (RTOS) and timer interrupt service
routine (ISR). The design of the middleware emphasizes minimization of sensor/actuator access delay to
improve performance.
This paper aims to introduce and summarize our development of a multi-algorithmic hybrid ADCS
system for a CubeSat, explain the procedure we used to verify this hybrid system by use of simulations
and a HILS, and present the on-flight results of such a hybrid system on the CubeSat CADRE which is
currently awaiting deployment onboard the International Space Station (ISS).
[1] Dennis, Louise, et al. "Satellite control using rational agent programming." Intelligent Systems, IEEE
25.3 (2010): 92-97.
11:30 AM
System Design and Assessment of a 100 W Power Management and Distribution Capability in a 3U
CubeSat
Katie Oriti - NASA Glenn Research Center
ABSTRACT
The Advanced eLectrical Bus (ALBus) CubeSat project is a technology demonstration mission of a 3-U
CubeSat with an advanced, digitally controlled electrical power system capability and novel use of Shape
Memory Alloy (SMA) technology for reliable deployable solar array mechanisms. The objective of the
project is to, through an on orbit demonstration, advance the state of power management and
distribution (PMAD) capabilities to enable future missions requiring higher power, flexible and reliable
power systems. The goals of the mission include demonstration of: 100 Watt distribution to a target
electrical load, efficient battery charging in the orbital environment, flexible power system distribution
interfaces, adaptation of power system control on orbit, and reliable deployment of solar arrays and
antennas utilizing re-settable SMA mechanisms. The power distribution function of the ALBus PMAD
system is unique in the total power to target load capability of 100 W, the flexibility to support
centralized or point-to-load regulation and ability to respond to fast transient power requirements.
Power will be distributed from batteries at 14.8 V, 6.5 A to provide 100 W of power directly to a load.
The deployable solar arrays utilize NASA Glenn Research Center superelastic and activated Nitinol
(Nickel-Titanium alloy) Shape Memory Alloy (SMA) technology for hinges and a retention and release
mechanism. The deployable solar array hinge design features utilization of the SMA material properties
for dual purpose. The hinge uses the shape memory properties of the SMA to provide the spring force to
deploy the arrays. The electrical conductivity properties of the SMA also enables the design to provide
clean conduits for power transfer from the deployable arrays to the power management system. This
eliminates the need for electrical harnesses between the arrays and the PMAD system in the ALBus
system design. The uniqueness of the SMA retention and release mechanism design is the ability to
reset the mechanism, allowing functional tests of the mechanisms prior to flight with no degradation of
performance. The project is currently in preparation at the NASA Glenn Research Center for a launch in
late calendar year of 2017. The 100 Watt power distribution and dual purpose, re-settable SMA
mechanisms introduced several system level challenges due to the physical constraints in volume, mass
and surface area of 3-U CubeSats. Several trade studies and design cycles have been completed to
develop a system which supports the project objectives. This paper is a report on the results of the
system level trade studies and assessments. The results include assessment of options for thermal
control of 100 Watts of power dissipation, data from system analyses and engineering development
tests, limitations of the 3-U system and extensibility to larger scale CubeSat missions.
11:45 AM
Model Based Design and Auto coding of an FPGA Based Satellite Control System
Jorden Luke, Charles Swenson - Utah State University/Center for Space Engineering
ABSTRACT
We describe the implementation of a low-power, radiation-tolerant field programmable gate array
(FPGA) satellite control system targeted for CubeSats. FPGA based control systems have advantages
over microprocessor systems in that they provide parallel and real time processing and can more easily
be radiation hardened. They can provide larger computational capability at low powers than a
microprocessor. A major drawback has been the inflexibility and difficulty in programming FPGAs
relative to the simplicity of using a microprocessor and a real time operating system. Another drawback
has been the difficulty in testing the FPGA design without complete hardware. Recently tool chains have
been developed by Mathworks that can auto code FPGAs directly from Simulink models. This
development process can mitigate difficulties in developing a fully FPGA based satellite control system.
Simulink can be used to verify the functionality and performance of the satellite control system as a
model of the high level algorithms. The Hardware Description Language (HDL) for the FPGA can be auto
generated from the Simulink model. The Simulink model can then be used in a hardware in the loop
verification of the FPGA performance.
We have used Simulink to model control systems for two different spacecraft subsystems. The first
being an Attitude Determination and Control System (ADCS) and the second being a controller for a
science payload. The Simulink model of the ADCS allows for testing of the algorithms in a way we can
track what is happening form input to output. This allows us to thoroughly understand the implantations
of the algorithms and test how data will be transferred between throughout the ADCS using flight
commands. These models have been auto coded to HDL and then placed on the FPGAs. We are
currently proceeding to a hardware in loop with model to verify that the hardware implementation
matches the model. This has allowed the use Simulink as a kind of testing interface for the FPGAs. With
the science payload we have done the same kind of hardware in the loop testing with the advantage
that the direct connection with Matlab simplifies the calibration process of the instrument. Data from
the payload is sent directly back to Simulink which is then analyzed in real-time. We report on the
advantages and disadvantages of using FPGA based state-machine verses microprocessor controllers
and how this is impacted by modern development tools.
12:00 PM
The Internet of Satellites: a C&DH software framework for small satellites built on open Internet
standards and software
Shaun Houlihan - Pumpkin Inc
ABSTRACT
Methods for satellite command & data handling (C&DH) system abound; flight software frameworks,
both open and closed source, are available to pick up and build on (e.g. NASA's cFS) and mission
developers often choose to build custom systems for their missions from the ground up. Existing flight
software packages can offer the advantage of rapid development, which is nothing to shrug off, and
custom solutions may eke out performance gains where it is critical. Both approaches, however, fail to
addresses a much larger challenge, which is to enable frictionless communication between satellite
nodes of various designs, ground stations, ground based sensors, and any resource available on the
Internet. Such a standardized approach to communication interfaces, if widely adopted, would not only
reduce barriers to flight software development, but would open up a huge array of networked
application possibilities that were not possible on traditional siloed satellite systems.
There are two steps necessary to enable this. The first is to treat satellites as fully as possible as you
would nodes on the Web: that is, as changing collections of data in universally standard formats that can
be accessed and acted upon, rather than as specialized machines to be controlled. The second is to
adhere to published international Internet standards and use only open source software for all
communication and data handling operations.
The Internet Engineering Task Force (IETF) has a published standard for Constrained Access Protocol
(CoAP), a transfer protocol that closely mirrors the functionality of the HTTP protocol but addresses the
needs of resource constrained nodes such as satellites and autonomous sensors. These constraints
include reduced bandwidth, unreliable connections, and limited power and memory. CoAP's 'ReSTful'
API and use of familiar URI path conventions make interfacing with the wider Web straightforward.
Along with standards for data formatting (e.g. JSON) it can completely describe the control and data
interface of a small satellite in a manner that can be replicated across satellite nodes. A CoAP server can
be installed on a flight computer running Linux, SQLite, and Python to create an 'LCSP' stack, analogous
to the well-known 'LAMP' stack that powers much of the Web.
We examine the process and results of implementing a 'LCSP' stack on a nanosat and look at the
implications that Internet standard interfaces could have on satellite operations and capabilities.
Session III: Big Picture
1:15 PM
Are We There Yet? Looking Back at a Decade Of Disruption of the Space Market Using Cubesats
Jeroen Rotteveel, Abe Bonnema - Innovative Solutions In Space BV
ABSTRACT
For the past 10 years ISIS - Innovative Solutions has been part of the CubeSat revolution after being
started as a Delft University spin-off in January 2006. In the past decade, CubeSat have become an
important element in the space domain as it offers a fast and affordable way for a wide array of
stakeholders to be active in space and allow for a fast innovation cycle.
Since the early days in 1999, when California Polytechnic State University at San Luis Obispo (Cal Poly)
and Stanford University developed a very small spacecraft concept to help universities worldwide to
enable students and researchers perform space science and exploration, the CubeSat movement has
come a long way.
Even though the original concept was never intended to pioneer a new space niche market and carve
out a position within the traditional space business, CubeSats have turned out to be a disruptive force in
the midst of a space sector that is slowly coming to terms that the market should accelerate its
transition towards a more commercially driven market.
A key element to a disruptive innovation is that it targets a new customer base, with different customer
requirements and decision drivers than the main market. CubeSats did exactly that over the past years
as students, universities, small companies and even individuals (e.g. through crowdfunding) became
satellite customers and broadened the overall space technology base. It also opened up many
opportunities for new actors to make their way to their space sector to extent the supply chain in the
sector, often adopting new technologies from outside the space business.
Can a concept remain disruptive for 10-15 years? For over a decade CubeSats hold promise of a different
way of doing space missions and although CubeSats have enabled a new and fast growing nichemarket
for themselves, an important questions remains on whether the concept has left its mark on the space
sector as a whole.
This paper will look back into the past decade of CubeSat activities and initiatives and elaborate on some
of the key innovations that CubeSats brought to the space sector. It will amongst others analyse
advances made in access to space, series production, managing high risk projects and the adoption of
non-space technology for space missions. It will investigate market dynamics and growth, public policy
changes and private initiatives all related to the effect CubeSats have had on the space business in the
passed years. In addition, the paper will address the spill-over effect to other areas of spaceflight and
provide a forward look for the decade to come.
1:30 PM
Pathfinder Technology Demonstrator: Demonstrating Novel CubeSat Technologies in Low Earth Orbit
John Marmie, Darin Foreman, John Hanson, Vanessa Kuroda, Scott Sawyer - NASA Ames Research
Center; Eric Pencil, Tim Smith - NASA Glenn Research Center
ABSTRACT
NASA's Pathfinder Technology Demonstrator (PTD) project will test the operation of a variety of novel
CubeSat technologies in low-Earth orbit, providing significant enhancements to the performance of
these small and effective spacecraft. Each Pathfinder Technology Demonstrator mission will consist of a
6-unit (6U) CubeSat weighing approximately 12 kilograms and measuring 30 centimeters x 25
centimeters x 10 centimeters.
The PTD project-led by NASA's Ames Research Center at Moffett Field, California, in collaboration with
NASA's Glenn Research Center in Cleveland, Ohio and a commercial partner-will benefit future missions
by demonstrating the operation of new subsystem technologies on orbit. These technologies include
propulsion systems that provide the capability to maneuver small science platforms and send small
spacecraft to deep space; novel technologies to stabilize spacecraft, and laser communications systems
that will greatly increase the amount of data that can be transmitted from the spacecraft to the ground.
As small spacecraft increase mobility and capability, NASA benefits by flight-qualifying these subsystems,
providing access to low-cost, highly capable, science and technology platforms that can operate from
the near-Earth to the deep space environment.
The PTD mission is funded through NASA's Small Spacecraft Technology Program (SSTP), which is
chartered to develop and mature technologies to enhance and expand the capabilities of small
spacecraft with a particular focus on communications, propulsion, pointing, power, and autonomous
operations. The SSTP is one of nine programs within NASA's Space Technology Mission Directorate.
This paper will include an overview of the PTD project, the PTD spacecraft bus interfaces and capabilities
as an adaptable, commercially developed small satellite bus for LEO technology demonstration,
potential types of payloads, expected timeframe and flights, and how the PTD project will be a
pathfinder for novel small spacecraft technologies to be flight demonstrated for science, commercial,
and governmental use.
1:45 PM
NASA Cube Quest Challenge: Citizen Inventors Advance CubeSats into Deep Space on 2018 EM-1
Mission
Jim Cockrell, Kay Twitchell, John Hanson - NASA Ames Research Center; Monsi Roman, Eric Eberly NASA Marshall Space Flight Center; David Klumpar - Montana State University
ABSTRACT
Cube Quest Challenge, sponsored by Space Technology Mission Directorate's Centennial Challenges
program, is NASA's first in-space prize competition. Cube Quest is open to any U.S.-based, nongovernment CubeSat developer. Entrants will compete for one of three available 6U CubeSat dispenser
slots on the EM-1 mission - the first un-crewed lunar flyby of the Orion spacecraft launched by the Space
Launch System in early 2018. The Cube Quest Challenge will award up to $5M in prizes.
The advanced CubeSat technologies demonstrated by Cube Quest winners will enable NASA,
universities, and industry to more quickly and affordably accomplish science and exploration objectives.
This paper describes the teams, their novel CubeSat designs, and the emerging technologies for CubeSat
operations in deep space environment.
Over a 2-year development period, teams demonstrate progress and vie for one of three available
dispenser slots on NASA's SLS vehicle through a series of ground-based competitions called "Ground
Tournaments". The first Ground Tournament (GT-1) was conducted in August of 2015. The remaining
three events are at roughly 6-month intervals. Judges assess the team's designs and mission plans for
technical excellence and compliance with rules and safety requirements. The top three winners of the
fourth Ground Tournament, scheduled for March 2017, will be selected for integration with the SLS
vehicle.
After being dispensed in a trans-lunar injection trajectory, the three competing CubeSats will boldly go
where no CubeSat has operated before, to compete at the moon and well beyond. The in-space
competition is also open to qualified teams that can procure their own launch.
There are two competition tracks: Lunar Derby requires teams to successfully achieve and maintain a
lunar orbit, while the Deep Space Derby will be conducted only after CubeSats have achieved a range of
over 4M km from Earth. Once in either lunar orbit or beyond 4M km, teams will attempt to achieve or
exceed communications data goals (rates and data volume over time), to survive the longest (up to a
year), and to successfully communicate from the farthest distance (for the Deep Space Derby).
To survive in deep space and demonstrate the rigor needed to operate at the moon or beyond and
attempt prizes, teams will have to push the envelope of CubeSat capabilities. Teams will have to
demonstrate advancements in propulsion in order to get into lunar orbit, in navigation without GPS or
Earth's magnetic field, in reliability, in fault tolerance and radiation hardening to survive and operate in
deep space beyond the Van Allen belts, and in long distance communications capabilities that no
CubeSat has previously demonstrated.
Twelve teams of "citizen inventors" registered for GT-1 and ten for GT-2. About two thirds of the
competitors are from academia, while the remaining teams are small companies. At GT-1 there was one
high school team and a team comprised of one individual engineer. Cube Quest is open to any team at
no charge. Teams develop CubeSats on their own time without government support.
2:00 PM
Quick-Turn, Low Cost Spacecraft Development Principles
John Abel - Tyvak Nano-Satellite Systems
ABSTRACT
Adoption of small spacecraft form factors and commercial off the shelf electronics can enable quickturn, low-cost development cycles. However, spacecraft miniaturization does not always involve
reduction in system complexity and poses many unique technical and programmatic challenges relative
to traditional aerospace approaches. Successful execution hinges on the availability of flexible
spacecraft bus hardware and software, vertically integrated development and agile program
management.
Leveraging these development principles, Tyvak Nano-Satellite Systems Inc. has managed numerous
parallel small-spacecraft development cycles. Activities within the last 18-months include three rapidturn 1U CubeSats, four state of the art 3U CubeSats, a multi-phase commercial CubeSat program
totaling five 6U CubeSats and five additional ongoing DOD and proprietary concept-to-launch vehicle
development efforts. Tyvak has launched and operated a number of these vehicles providing end-toend technology and process validation as well as invaluable lessons-learned benefiting ongoing
enhancement of institutional best-practices.
An overview of Tyvak's quick-turn missions is provided, with specific emphasis on the ever-evolving
development cycle principles as influenced by lessons learned from Tyvak's design-build-operate
experience.
2:15 PM
How CubeSats are Helping Address the Space Debris Problem: Results from the Polar Orbiting Passive
Atmospheric Calibration Spheres
Marcin Pilinski - ASTRA; Gilbert Moore - Project POPACS
ABSTRACT
Satellite drag variability caused by the dynamics of the upper atmosphere is a major cause of orbit
specification and prediction errors in Low Earth Orbit. The problem is particularly severe during
geomagnetic storms. These storms can severely degrade the accuracy of conjunction analysis between
debris and spacecraft with LEO perigees and all other resident space objects. The Polar Orbiting Passive
Atmospheric Calibration Spheres (POPACS) were launched as secondary payloads on the September
29th, 2013 Falcon 9 launch. Their purpose is to provide stable and well defined atmospheric calibration
objects leading to improved specification of atmospheric densities and satellite drag.
POPACS consists of three spheres deployed successfully from a Planetary Systems Corporation CSD 3U
CubeSat ejection system. Specially designed spacers separated the spheres during launch and
deployment. After summarizing the POPACS mission parameters and design, we review early mission
validation results including data comparisons with the Drag and Atmospheric Neutral Density Explorer as
well as comparisons with various atmospheric models.
We also look at the ability of the POPACS data to alert us to large changes in atmospheric densities and
satellite drag during geomagnetic storms. Finally, we show that well-designed reference satellites, such
as POPACS, can be used to calibrate the state of the atmosphere. This calibrated data can be used to
improve global atmospheric modeling and orbital predictions for both space debris and active satellites.
2:30 PM
Citizen Satellite: A Way to have Low Cost Space Missions for the Unordinary Innovator
Robert Twiggs - Morehead State University; Tony So, Ted Tagami - Magnitude.IO; Amin Djamshidpour Teton Systems
ABSTRACT
The ten centimeter cube Cubesat and the P-POD deployer, although not intended, has brought about a
major change in space missions. When introduced in 1998 and first launched in 2003, the CubeSat
originally proposed for the academic community along with the commercial miniaturization of the
electronics has now been whole heartedly accepted by the space community. Along with many
academic and scientific missions there is now a rapidly growing commercial community of unique
applications.
With this acceptance though, the original intent for academic training has been greatly diminished due
to the increased complexity of getting approval for launch and the cost of the launches. Some relief has
been provided by the NASA ElaNa program, but this is still a complex and time consuming meeting and
paperwork process that mostly benefits experience academic organizations or professional space
industry.
What we propose with the Citizen Satellite is to take a step down in size, cost and complexity of a space
mission for unexperienced academic community and the novice space enthusiast to get an experiment
into space. As with the CubeSat originally, the reduction is size and the use of the P-POD provide a less
expensive way to get secondary launches to space. Now the addition of the International Space Station
low altitude launches eliminates the objection of long term space debris. This short orbit life, however,
meets the needs of this new space community.
The Citizen Satellite is now based around a five centimeter cube. A deployer has been developed by
Teton Sys that is the form factor of a 3U CubeSat called a PQ-POD that can use the standard P-POD. The
small five centimeter cubes called PocketQubes are contained within the 3U CubeSat that has its own
space mission bus. This bus then releases the PocketQubes at some time after the deployment from the
P-POD. The present PQ-POD can hold sixteen five-centimeter PocketQubes (1p), or other combinations
of 2p and 1p sizes. Our primary launch platform is the ISS so all will have a short orbit life.
The first PocketQubes were launch with the GAUSS Team UniSat in 2013 on a Russian Dnepr. These
small femtosats costing less than $1,000 proved that off-the-shelf low-cost electronics can work for
introductory space missions. Our hope is that these Citizen Satellite PocketQubes will encourage the
novice space enthusiast to provide innovation for new and useful applications for space as the apps has
done for the iPhone.
Session IV: LEO Missions
3:15 PM
A Preliminary Design for the INSPIRESat-1 Mission and Satellite Bus: Exploring the Middle and Upper
Atmosphere with CubeSats
Loren Chang, Jude Salinas, Jack Chieh Wang, Jia-Yu Su, Duann Yi, Joe Hong, Yi-Chung Chiu - National
Central University; Steven C.R. Chen - National Space Organization
ABSTRACT
Spanning an altitude range from 20 - 1000 km, the Earth's middle and upper atmosphere forms the
interface between the Earth system and near Earth space. Driven by solar activity, geomagnetic storms,
as well as waves and tides propagating upward from below, the winds and temperatures in this region
have important implications both for the Low Earth Orbit space environment, as well as understanding
vertical coupling processes in the atmosphere as a whole. However, existing satellite measurements of
this region are limited both in spatial and temporal coverage. There is therefore a need for compact
sounding payloads that may be deployed using small satellites satisfying the payload requirements.
As part of the International Satellite Program in Research and Education (InSPiRE), we present a
preliminary design and analysis for InSPiRESat-1: a CubeSat mission carrying the Doppler Wind and
Temperature Sounder (DWTS) instrument being co-developed by CU LASP, GATS Inc. and BrandyWine
Photonics. This design for InSPiRESat-1 was spearheaded by students from National Central University
(NCU) in Taiwan, in collaboration with Taiwan's National Space Organization (NSPO). The final design for
InSPiRESat-1 will be based upon this design, in conjunction with parallel designs from other universities
participating in the InSPiRE consortium.
3:30 PM
Outernet: The Development of 1U CubeSat Platforms to Enable Low-Cost Global Data Provision
Pamela Anderson, Craig Clark - Clyde Space Ltd; Syed Karim – Outernet
ABSTRACT
The Outernet constellation aims to revolutionize telecommunications provision by offering a low-cost,
mass-producible alternative to traditional infrastructure. Highly-capable 1U CubeSats, manufactured by
Clyde Space for Outernet Inc., will provide the solution. The UK Space Agency have part-funded
development of three platforms, due to be launched in Q3 2016, as an in-orbit demonstration (IOD) of
the full Outernet concept. These initial platforms are intended to be a precursor to a 200-satellite
constellation, and will test much of the functionality of the full constellation, which aims to provide low
data-rate global broadcasting specifically for remote regions of the World. Each spacecraft will receive
data streams from a network of ground stations and the data transmitted to the user's hand-held
devices on the ground.
Traditional telecommunications platforms typically have a mass of the order of a few tonnes, cost
several million dollars and take a number of years to develop. Therefore, the development of 1U
CubeSats with the ability to distribute information across a constellation and subsequently transmit it to
receivers is not trivial. Some of the challenges of the Outernet CubeSats are: power generation, volume,
high duty cycle operation and satellite batch production techniques.
To overcome these challenges, the platforms will incorporate a number of state-of-the-art Clyde Space
subsystems. Power will be provided by a bespoke version of the standard 1U solar panels consisting of
body mounted and deployable panels to maximise power generation. These solar panels will also host
coarse sun sensors, capable of providing illumination information, along with temperature sensors.
Power conditioning will be performed using an off-the-shelf next-generation Clyde Space electric power
system with an integrated 20Wh battery. Outernet platforms will also include the newly developed onboard computer which will carry out all platform and mission control and management and will provide
the on-board storage necessary for payload operations. The attitude determination and control system
will be the Clyde Space motherboard with standard on-board sensors and will interface to the solar
panel embedded magnetorquers, coarse and fine sun sensors. A modified VHF/UHF transceiver (VUTRX)
will be the primary transceiver for telecommand, telemetry, and payload data. The VUTRX will provide a
VHF uplink and UHF downlink at nominal rates of 9600bps using modified CCSDS packets and a resilient
broadcast protocol. The bespoke 1U CubeSat structure has also been designed with the necessary
interface and aperture cut-outs to satisfy the Outernet subsystem requirements.
The Outernet IOD mission will allow understanding of the platform from subsystem level to full
operation (provision of data to the fixed Earth station and pick up by a simple receiver at a different
location) to extrapolate the expected performance of a future full Outernet constellation. The
completeness of the received data, the effect of missing packets and the end to end reliability will be
assessed.
This paper provides an overview of the ambitious Outernet IOD mission where Clyde Space will push the
boundaries of platform development to enable Outernet to pursue its goal of offering a near continuous
broadcast of humanitarian data to those most in need.
3:45 PM
Athenoxat-1, Night Vision Experiments in LEO
Giulio Manzoni, Yesie Brama, Meini Zhang, Naushad Rahman - Microspace Rapid Pte Ltd
ABSTRACT
On 16th December 2015 Athenoxat-1 was launched by a PSLV from India in to Equatorial Orbit.
Athenoxat-1 has been developed by Microspace Rapid Pte Ltd to demonstrate the feasibility of night
vision imaging on a 3U Cubesat. The night vision payload is based on a high sensitive CCD and, in
combination with the large optical aperture allows for very fast imaging of Earth surface in the night
with 25m resolution. In addition to the main payload, Athenoxat-1 is equipped with 4 optical payloads
for wide angle and horizon imaging. Sensor placement allows capturing a synchronized view of Earth
and Space across almost 4Pi steradians thereby allowing various ADCS experiments such as Nadir
determination and Moon tracking. Attitude control is achieved by magnetorquers and reaction wheels
specifically developed for this mission. The talk will focus on the mission achievements, difficulties and
challenges and, while discussing the lessons learned, will trace a roadmap for future work.
4:00 PM
Retooling Space Solar Cell System CIC for CXBN-2
Jacob Wade, Eric Thomas - Morehead State University
ABSTRACT
The power subsystem is vital to any spacecraft operation, making solar cells a valuable aspect. Critical to
all spacecraft, they provide constant charge to the batteries and produce power for the electronics onboard. Solar cells have been engineered for large commercial and military space missions, up to
thousand kilogram class satellites, and may not fit the requirements for smaller CubeSat form factors.
Additionally, this restrains CubeSats from using higher voltage busses due to the mismatch in solar cell
scaling. The purpose of this project is to retool the solar cell CIC (Solar Cell Interconnects Coverglass) to
satisfy the small satellite system requirements while having the most effective surface area and
providing the necessary wattage. We have undertaken an experimental process to dice commercial solar
cells to customize them for the CXBN-2 (Cosmic X-Ray Background NanoSat 2) mission. CXBN-2 is
constrained by having two scientific payloads extruding outward from the space frame in opposite
directions that make fitting large format solar cells impossible. Staff and students from the Morehead
State University Space Science Center and the Micro-Nano Technology Center at the University of
Louisville are developing a process to dice existing commercial off the shelf solar cells to facilitate
mission customization. The CXBN-2 mission provides an opportunity to develop these processes. This
project will reveal the design decisions, dicing, testing, and model verification of the modified solar cells
that will be mounted onto the spacecraft body and deployable solar panels, achieving higher power
system performance.
4:15 PM
MakerSat: A CubeSat Designed for In-Space 3D Print and Assembly
Braden Grim, Mitch Kamstra, Aaron Ewing, Connor Nogales, Joshua Griffin, Stephen Parke - Northwest
Nazarene University
ABSTRACT
We are engaged in historic proof-of-concept missions that will ultimately deploy into orbit from the ISS,
the first 3D-printed cubesat that has been explicitly designed to be easily and safely crew-assembled in
microgravity. MakerSat will be the first satellite or spacecraft ever built in space! The first MakerSat
mission will be on ELaNa XX in 2017.
We have been engaged the past two years in a technology development partnership between
Northwest Nazarene University (NNU) engineering students in Idaho and Made In Space (MIS) at NASA
Ames. During this time, we have designed and developed a simple-to-assemble 1U cubesat, named
MakerSat, which utilizes a structural frame that will be 3D-printed on MIS’s new Additive Manufacturing
Facility (AMF) that is already printing aboard the ISS. MakerSat’s polyetherimide (PEI) 3D printed frame
rails slide and snap securely together with six PCB/solar panel assemblies. This eliminates the need for
using any small fasteners or tedious assembly, which would be difficult, time consuming, and potentially
hazardous for the ISS crew if accidentally released into the ISS cabin. Following MakerSat’s print and
simple snap-together assembly, it will be USB charged and tested, followed by deployment into orbit
using the “Stash and Deploy” model announced by Made In Space and NanoRacks at the 2015 SmallSat
conference.
MakerSat is also a multi-project satellite that provides four different research teams the opportunity to
fly their science with very low project complexity and cost. All satellite power, computing, and radio
communication tasks are supplied to the four science team boards in a round robin fashion by our
MSP430-based “Hub” controller. The four science teams will each personalize a science board with their
own sensors and code, passing their data to the radio downlink via the Hub. Student teams will be able
to do design and programming of their space science experiments from their own Makerspace here on
earth, then upload them to the ISS to personalize MakerSat science boards that are already stored
there. These will then be assembled on-demand, along with a Hub and an EPS/radio board, into frames
that are 3D-printed onboard the ISS. After assembly, charging, and test, MakerSats will be gently
launched from the ISS directly into low earth orbit. This methodology makes it possible to design, build,
test, and orbit cubesats on-demand, in much larger numbers, at lower cost, and with more design
iterations possible. Because these satellites will never have to experience a high-g launch, it will now be
possible to design more intricate and fragile 3D printed CubeSat structures and sensors that might not
even be able to withstand their own weight on Earth.
On our first MakerSat mission, we are particularly interested in the space worthiness of a variety of
polymer materials that have been 3D printed on the ISS AMF. These polymers, such as ABS, PEI, PMA,
are susceptible to outgassing, monoatomic oxygen erosion, and UV degradation while in orbit, resulting
in mass and structural integrity loss. To quantify these effects, we have designed a novel experiment to
monitor the mass loss of these polymer samples continuously throughout the MakerSat orbit. We are
flying an array of small piezo-resistive micro-cantilevers that are each loaded with a different small
polymer sample. These samples are directly exposed to the space environment through small windows
in the satellite exterior. These cantilevers are excited by a small vibration motor over a 40-60Hz range of
frequencies, while sensing their various resonant frequencies, using an FFT algorithm. The system can
resolve 0.1Hz changes, versus an unloaded, unchanging reference cantilever. We anticipate seeing at
least a 10% mass loss for ABS (poor material choice) over a year-long mission, which will result in a 2Hz
increase in cantilever resonant frequency. By studying the real time degradation of 3D printed polymer
structures in space, we will allow good material choices to be made for future 3D printed spacecraft.
4:30 PM
RSat Flight Qualification and Test Results for Manipulable Robotic Appendages Installed on a 3U
CubeSat Platform
Dakota Wenberg, Benjamin Keegan, Morgan Lange, Edward Hanlon, Jin Kang - United States Naval
Academy
ABSTRACT
Satellites cannot return to Earth for repair if they are damaged, malfunction or fail to deploy as planned.
Even simple, non-catastrophic failure can cripple a spacecraft and severely impede research efforts.
Plans for a robotic repair force have been proposed, but the cost remains prohibitive. One way to make
on-orbit diagnosis and repair a reality is to miniaturize functionality. As part of its Autonomous Mobile
On-orbit Diagnostic System (AMODS), which was recently selected to participate in the University
Nanosat Program, the United States Naval Academy has constructed a 3U CubeSat equipped with
robotic arms and manipulators, allowing it to latch on to and maneuver around a client satellite in order
to take pictures, make small repairs and otherwise support satellite diagnostics. RSats may either be
incorporated directly into the design of a new spacecraft or colaunched with a modular transport vehicle
- another 3U CubeSat (BRICSat) specially designed to seed RSats across a constellation of on-orbit client
satellites. This unique delivery method spreads the cost of otherwise unnecessary ADCS, Propulsion and
Rendezvous Systems across the entire constellation. Because RSats do not require propulsive or
navigational capability, functionality requirements focus on robotic orbital operations and launch
tolerance.
The space environment simplifies robotic operations. In zero gravity, any torque output will allow RSat
to move components or to locomote - given time - allowing the design team to focus on length,
dexterity and accuracy over brute force. Using less powerful and more accurate motors also allowed the
design to scale to the CubeSat form factor. With minor alterations (all in accordance with the CubeSat
Developers Manual), the CubeSat frame was modified to create a secure storage for the twin seven
degree of freedom 60 cm long arms, allowing the RSat to maneuver in and out of very tight areas. Long
term accuracy tests and a closed loop control algorithm facilitate arm accuracy at full extension of ±10
mm.
But space also offers unique challenges. Motors and motor lubricants must be vacuum tolerant. They
must not be dependent on convective cooling, and must also function for long durations without repair.
Extensive testing was completed to assure these capabilities in RSat. Similarly, the arms, manipulators
and motors themselves must survive launch forces. A wedge system was created to restrict movement
to only one plane while custom dual burn resistor blocks provide security in that plane. Iterative
vibration testing was made possible through 3D printing's rapid prototyping capability, allowing the
design of the robotic appendage, its motor and launch duration stability to converge.
A launch targeted for early 2017 will validate RSat's on-orbit capability with the execution of a test
pattern or patterns intended to simulate simple diagnostic or repair tasks.
This presentation will discuss the development and testing of RSat, including design and programming
considerations covering precision manipulation, arm capability, proximity operation and launch
tolerance. The presentation will detail critical test results, how they affected design decisions and their
overall implications for robotization on the small satellite platform.
4:45 PM
CubeSat Nighttime Lights
Dee Pack, Brian Hardy - The Aerospace Corporation
ABSTRACT
Monitoring of visible emissions at night from satellites has evolved into a useful capability for
environmental monitoring and mapping the human footprint globally. Pioneering work with Defense
Meteorological Support Program (DMSP) sensors has been followed by new work with the Visible
Infrared Imaging Radiometer Suite (VIIRS), and International Space Station (ISS) photography. We have
been investigating the ability of CubeSats to carry out nightlights mapping missions and present recent
results from existing visible wavelength cameras on AeroCube satellites. CubeSat sensors were
successfully tasked to image oil industry natural gas flares in the Persian Gulf region, urban areas and
other sites of interest. Point and stare maneuvers to maximize resolution and sensitivity were
demonstrated. Our initial work demonstrates both the ability of CubeSats to conduct nightlights
missions, as well as the limitations of the small cameras flown to date. Comparison of VIIRS and
AeroCube imagery are made. Potential uses of the CubeSat platforms include: 1) providing different
overpass times than the early morning overpass provided by VIIRS to potentially spot missing lights
activity, 2) providing multi-color nightlights to supplement the monochromatic VIIRS day-night-band
(DNB) data, and 3) "swarming" the nighttime mission with multiple platforms to provide more frequent
taskable data on transient events such as fires, volcanic activity, and natural disaster power outages.
CubeSats sensors may be able to improve mapping of the human footprint in targeted regions via
nighttime lights and contribute to better monitoring of: urban growth, light pollution, energy usage, the
improvement of electrical power grids in developing countries, and oil industry flare activity. Future
CubeSats sensors should be able to contribute to nightlights monitoring efforts by NOAA, NASA, ESA, the
World Bank and others. Our current results will be summarized and next steps discussed, including
soon-to-be-launched sensors and future program development.
5:00 PM
Nodes: A Flight Demonstration of Networked Spacecraft Command and Control
John Hanson - Millennium Engineering and Integration; Ali Luna, Rodolphe DeRosee - NASA Ames; Ken
Oyadomari, Jasper Wolfe, Watson Attai, Cedric Priscal - Stinger Ghaffarian Technologies
ABSTRACT
Nodes is a pair of 1.5 U Cubesats developed by the NASA Ames Research Center under the Small
Spacecraft Technology Program (SSTP) within NASA Space Technology Mission Directorate (STMD). The
Nodes spacecraft were launched to the ISS in December, 2015 and deployed from the ISS in late March
of 2016. Nodes is designed to expand the utility of small spacecraft networks and to explore issues
related to the command and control of swarms of multiple spacecraft making synchronized, multipoint
scientific measurements. Networked swarms of small spacecraft will provide new insights in the fields
of astronomy, Earth observations and solar physics. Their range of applications include the formation of
synthetic aperture radars for Earth sensing systems, large aperture observatories for next generation
telescopes and the collection of spatially distributed measurements of time varying systems, probing the
Earth's magnetosphere, Earth-Sun interactions and the Earth's geopotential. While these swarms have
great potential, they create new challenges to the Cubesat community related to managing large
numbers of spacecraft in close proximity. The Nodes mission addresses these challenges through three
primary objectives. The Nodes spacecraft will autonomously self-organize, selecting which spacecraft
will lead the formation, collect data and pass those data to the ground, all based on the states of the
spacecraft. It will also demonstrate the commanding of spacecraft in a swarm, from the ground and
through the network. Finally, Nodes will make synchronized, multi-point science measurements of the
Earth's charged particle environment. This paper describes the Nodes spacecraft and mission and
preliminary results from the Nodes flight experiment. Furthermore, the communications architecture
and approach to managing swarms of spacecraft are discussed. Finally, future network enhancements
that can be built on top of the current Nodes hardware are suggested.
Session V: Guidance and Control
9:00 AM
New Tools for the ELaNa Program
Garret Skrobot - NASA Kennedy Space Center
9:15 AM
Small Mission Opportunities for the Vega launch System: The Small Spacecraft Mission Service
Fabio Caramelli - European Space Agency
9:30 AM
MinXSS CubeSat On-Orbit Performance and the First Flight of the Blue Canyon Technologies XACT 3axis ADCS
James Mason - University of Colorado, Boulder; Matthew Baumgart - Blue Canyon Technologies; Thomas
Woods - University of Colorado, Boulder; Daniel Hegel, Bryan Rogler, George Stafford - Blue Canyon
Technologies; Stanley Solomon - National Center for Atmospheric Research; Phillip Chamberlin NASA
Goddard Space Flight Center
ABSTRACT
The Miniature X-ray Solar Spectrometer (MinXSS) 3U CubeSat was launched to the International Space
Station (ISS) on 2015 December 6. Its deployment from the ISS is scheduled for 2016 March. MinXSS was
designed and developed at the University of Colorado Boulder through a graduate project class, with
significant professional support from the Laboratory for Atmospheric and Space Physics (LASP). The 3axis attitude determination and control system (ADCS) is the Blue Canyon Technologies (BCT) XACT. This
is the first flight of the XACT unit, which is the most capable commercially available 3-axis ADCS for
CubeSats on the market today.
MinXSS is a science mission funded by NASA's Heliophysics division and is the first CubeSat to be flown
from NASA Science Mission Directorate's new CubeSat Implementation Panel. The primary objective for
the MinXSS mission is to better understand the energy distribution of solar soft x-ray (SXR) emissions
and their impact on earth's ionosphere, thermosphere, and mesosphere (ITM). MinXSS observes the
solar SXR spectrum between 0.5 to 30 keV with an energy resolution of 0.15 keV full width half
maximum at 5.9 keV. Very few prior spectrally-resolved solar observations exist in the SXR range, leaving
a critical gap in our ability to determine the spectral energy distribution for ITM modeling and solar flare
studies. These issues can be addressed with new MinXSS data.
This paper will provide details of the on-orbit performance of MinXSS and first-light observations from
the primary science instrument, which is a commercially available system that was modified for flight.
First light observations will include the first solar SXR spectrum from MinXSS and comparisons between
quiet-Sun and flare spectra as observed by MinXSS.
MinXSS represents the first opportunity for on-orbit characterization of BCT's XACT ADCS. Performance
of star tracker-based attitude determination, 3-axis reaction wheel-based attitude control, and torque
rod-based momentum control will be assessed using on-orbit telemetry. This system is being used by
several NASA centers, the DoD, many universities, and commercial entities for a multitude of upcoming
missions that require precision attitude control at low cost.
The exceptionally simple design of the LASP PPPT will be reviewed. The addition of a single fixed-value
resistor mitigates the high current draw from the battery, which prevents the solar cell voltage from
dropping below buck converter input requirements. The PPPT was successful in increasing the power
output of the electrical power system by nearly a factor of 2 in mission simulations. The on-orbit power
performance will be analyzed.
In addition to thermal vacuum testing, MinXSS underwent thermal balance, which is dedicated to tuning
the thermal model. The thermal balance procedure and model will be briefly overviewed and
predictions compared to on-orbit temperatures. The results of this analysis have been generalized such
that other CubeSat programs, who may not have the means to perform the test, may apply the results
to their models and get improved model predictions. Thermal control of CubeSats is important to their
lifetime and few if any prior results on this topic have been previously presented.
9:45 AM
Laboratory Validation of Vision Based Grasping, Guidance and Control with Two Nanosatellite Models
Subhransu Mishra, Max Basescu, Marin Kobilarov - The Johns Hopkins University, Applied Physics Lab
ABSTRACT
The goal of this work is to demonstrate the autonomous proximity operation capabilities of a 3U scale
cubesat in performing the simulated tasks of docking, charging, relative navigation, and deorbiting of
space debris, as a step towards designing a fully robotic cubesat. The experiments were performed on
an air-bearing testbed, using an engineering model of a 3U scale cubesat equipped with cold-gas
propulsion. An appendage with a gripper is integrated into the model to enable grasping. Onboard vision
and control algorithms are employed to perform precise navigation and manipulation tasks. Three
experiments incorporating the tasks above have been successfully demonstrated.
Hardware: The experimental setup consists of two 3U cubesat engineering models, an air-bearing
testbed, and a motion capture system. The current cubesat model is derived from a previous version
that has been used to demonstrate autonomous point-to-point navigation and obstacle avoidance tasks.
The cubesat model consists of the following main subsystems: 3D printed cold-gas propulsion, sensing
and computing, and power. In addition, we developed and integrated an appendage with a multipurpose end effector that is effective in grasping objects, docking to, and charging a second cubesat
model. The sensor suite consists of pressure sensors, an inertial measurement unit (IMU), short range IR
sensors, and a camera. An Odroid XU4 computer with an octa-core processor was chosen to satisfy the
computational, power, and form constraints of the model.
Software: The perception and control algorithms used for the proximity operations were developed and
implemented using an open source robotics software framework called Robot Operating System (ROS)
as a middleware for communication. The perception algorithm estimates the 3D pose and rate of
change of the cubesat and objects of interest in its vicinity. The object detection requires a textured 3D
model of objects and works by matching SURF features of a given image to those generated from the 3D
model. The object tracking employs KLT tracking with outlier detection to obtain robust estimates. The
textured 3D model is constructed from multi-view images, however, it can also be generated from CAD
models. A state machine is employed to automatically switch between the desired control behaviors.
Experiment: The system's performance is validated through three experiments showcasing precise
relative navigation, docking, and reconfiguration. The first experiment is a simple docking and
reconfiguration maneuver, in which a "primary" cubesat detects and navigates to the closest face of a
passive "secondary" cubesat, upon which it deploys its appendage and docks. The primary then
navigates the joined system to a final goal position. In a variation of this experiment, after docking, the
primary transmits power to the secondary which is indicated by an LED. The next experiment explores
the scenario of debris deorbiting. Similar to the first experiment, the docking procedure is performed,
followed by unlatching and release of the secondary with a desired velocity vector. In the last
experiment, the primary and secondary execute relative navigation along a set path while maintaining
formation.
Additional details can be found here: https://asco.lcsr.jhu.edu/nanosatellite-guidance-navigation-andcontrol
10:00 AM
The Ranging and Nanosatellite Guidance Experiment (RANGE)
Brian Gunter, Byron Davis, Glenn Lightsey, Robert D. Braun - Georgia Institute of Technology
ABSTRACT
The Ranging And Nanosatellite Guidance Experiment (RANGE) cubesat mission was recently selected for
a flight opportunity as part of the Skybox University Cubesat Partnership, with a tentative launch date
scheduled for 2016. The RANGE mission involves two 1.5U cubesats flying in a leader-follower
formation with the goal of improving the relative and absolute positioning capabilities of nanosatellites.
The satellites' absolute positions will be tracked using GPS receivers synchronized with miniaturized
atomic clocks, and will be validated using ground-based laser ranging measurements. The relative
position of the satellites will be measured using an on-board compact laser ranging system, which will
also double as a low-rate optical communication system. The satellites will not have an active
propulsion system, so the separation distance of the satellites will be controlled through differential
drag techniques. The results of the mission should serve to enable more advanced payloads and future
mission concepts involving formations and constellations of nanosatellites. The presentation will give
an overview of the mission design and status, as well as the key innovations and expected outcomes.
10:15 AM
Attitude Determination and Control System Design for STU-2A CubeSat and In-Orbit Results
Guowen Sun, Xiwang Xia, Shufan Wu, Zhiyi Wu, Wen Chen - Shanghai Engineering Center for
Microsatellites
ABSTRACT
STU-2A, a 3U CubeSat developed by Shanghai Engineering Center for Microsatellites, along with the
other two 2U CubeSats and one MicroSat, has been sent into a 481km sun-synchronous orbit by CZ-11
launch vehicle with its maiden journey. As the first batch of CubeSats in China that is made in
accordance with CubeSat standard, the 2.9kg satellite is featured with the on-board CMOS color camera
for taking pictures of polar glacier, Gamalink for Cubesats Networking, MEMS based cold-gas
micropropulsion for attitude/orbit maneuver and formation flight and precise ADCS module for
technology demonstration.
The ADCS module, equipped with two 3-axis magnetometers, 1 fine Sun sensor, five coarse Sun sensors,
one three-axis MEMS gyro, one Nano-scaled star tracker, three magnetic coils and three reaction
wheels, would provide three-axis stabilization and maneuver capability. Combining the attitude sensors,
TRAID and unscented Kalman Filter (UKF) algorithms are adopted to determine the attitude knowledge.
Some attitude control modes, such as damping control, Sun-pointing, magnetic-based nadir pointing,
momentum-biased stabilization and reaction wheels-based control, are designed to achieve the prefect
attitude.In-Orbit data received by ground station verified the performance of ADCS of STU-2A.
10:30 AM
Simulation Results of Alternative Methods for Formation Separation Control
Thomas Heine, Charles Bussy-Virat, Mark B. Moldwin, Aaron J. Ridley University of Michigan
ABSTRACT
Missions that want to maintain specific separation distances have previously relied on propulsion
systems or aerodynamic actuators to compensate for differential drag effects. These systems can be
complex and resource consuming for resource constrained missions like SmallSats. For example, the
SCintillation and Ionospheric Occultation Nanosats (SCION) mission requires separation distances
between its two 1U CubeSat spacecraft on the order of 10 km for at least 90 days. Ensemble runs on an
orbit propagator that models aerodynamic drag demonstrate the validity of alternatives to propulsive
and actuator-based separation control such as coarse attitude control and spin-averaged drag matching
to meet such requirements. Initial results suggest that separation distances less than 1 km are possible
at least 10 days into the mission and further simulations will demonstrate the potential to restrict
separation distance for even longer periods of time.
Session VI: Propulsion
11:15 AM
Development of a Nitrous Oxide-Based Monopropellant Propulsion System for Small Satellites
Vincent Tarantini, Ben Risi, Robert, Nathan Orr, Robert Zee Space Flight Laboratory, University of
Toronto
ABSTRACT
As the demand for highly capable microsatellite missions continues to grow, so too does the need for
small yet effective satellite technologies. One area which needs to be addressed is compact propulsion
systems capable of performing on-orbit maneuvers, station keeping, and de-orbit impulses with good
efficiency. Another important consideration for propulsion systems is the safety and ease in handling,
integrating, and testing the propulsion system. This is particularly important for small satellites in order
to maintain simplicity by avoiding toxic propellants such as hydrazine. In response to this demand, the
Space Flight Laboratory has developed its next generation propulsion system which builds on the
experience of the Canadian Nanospace Advanced Propulsion System (CNAPS), a cold gas system that
enabled the successful CanX-4/CanX-5 formation flying mission in 2014. The new propulsion system uses
nitrous oxide (N2O) as the propellant. The benefits of nitrous oxide are that it is safe to handle, non
toxic, cheap, and much easier to access and transport than traditional propellants. Nitrous oxide also
self pressurizes to 50.5 bar (733 psi) at 20 °C and thus does not require the addition of a pump or
pressurant gas to move the propellant; this allows the tank and feed system design to be much simpler
than for liquid propellants. Nitrous oxide can also be used as monopropellant, that is to say that it can
be exothermically decomposed to provide an increase in efficiency from an input power point of view.
This paper summarizes SFL's effort in the development of this system. A 100 mN resistojet was initially
developed. The performance using nitrous oxide was verified with a specific impulse of 100 s and input
power of <75 W. In the next stage of development, a monopropellant version of the thruster was
developed. The 100 mN monopropellant thruster has successfully demonstrated sustainable nitrous
oxide decomposition with a specific impulse of 148 s and operational endurance of greater than 50
hours. Current research focuses on evaluating different catalysts and further extending the operational
lifetime of the system.
11:30 AM
Flight Development of Iodine BIT-3 RF Ion Propulsion System for SLS EM-1 CubeSats
Michael Tsay, John Frongillo, Joshua Model, Jurg Zwahlen - Busek; Benjamin Malphrus - Morehead State
University
ABSTRACT
Busek previously developed a 3cm RF ion thruster known as BIT-3 that was the world's first iodinefueled gridded ion thruster. The 60W prototype thruster completed a 500-hour endurance test on
iodine and was shown capable of delivering 1.3mN thrust and 3200sec Isp nominally, excluding
neutralizer flow. This exceptional performance, combined with the many benefits of iodine propellant,
has led to a number of CubeSat flight opportunities on NASA's SLS EM-1 mission. The first confirmed
EM-1 mission for the thruster is onboard the 6U "Lunar IceCube" spacecraft that is being developed by
Morehead State University and its partners. This paper will describe the technological advances made
to date on the BIT-3 system and the remaining development to flight readiness. Specifically it will
include updates on the thruster design and power optimization, measured thruster and Isp performance
with an innovative RF cathode neutralizer, and details regarding the flight iodine feed system and power
electronics module. In addition, it will include an overview of the BIT-3 system's digital
command/control structure and mechanical interfaces in the context of the Lunar IceCube bus.
The BIT-3 ion thruster's ability to use iodine as propellant is a huge game-changer for CubeSats, as
iodine is stored in high-density solid form (4.9g/cc vs. xenon's 1.95g/cc at 2000psi) devoid of bulky
pressure vessels. The solid storage property makes iodine-fueled propulsion systems safe and facilitates
compliance with range safety requirements, which is especially important for secondary payloads. The
sub-Torr storage vapor pressure also allows for thin-walled, lightweight and conformal tanks that could
further reduce the overall volume and mass budget impact without compromising performance. For
example, Lunar IceCube's tightly packaged 2U iodine BIT-3 system can provide more than 2km/s delta-V
to a 6U/14kg CubeSat for lunar or other deep-space missions. Such unprecedented capability can help
increase the practicality and appeal of CubeSats alike, ultimately gaining acceptance within the science
community as a viable platform for future robotic exploration missions to destinations currently
unachievable with small satellites.
11:45 AM
In-Orbit Demonstration of a MEMS-based Micropropulsion system for Cubesats
Kristoffer Palmer - NanoSpace; Zhao Li, Shufan Wu - Shanghai Engineering Centre for Microsatellites
ABSTRACT
Cubesats is rapidly maturing beyond educational projects and low cost technology demonstrators.
Today we want cubesats to provide useful data with a scientific or commercial value. One of the unique
advantages of cubesats is that the size and cost enables large numbers of satellites to be built and
launched at the same time. Both commercial examples such as Planet Labs or SPIRE as well as scientific
mission like QB50 are utilizing fleets of cubesats to achieve valuable or unique data that was not
thinkable a decade ago. However, there are still a few more steps to be taken in order to make fleets or
constellations of cubesats even more viable or efficient in providing useful data. One field that is still
immature is propulsion. Propulsion capability on every cubesat in a large constellation can provide faster
deployment, better dispersion, longer life time and possibly also controlled de-orbit of the satellites at
end of life.
NanoSpace has for more than a decade worked on a various types of miniaturized propulsion using
MEMS (Micro Electro Mechanical Systems) technology. In 2015 the first flight of a MEMS-based
propulsion system for cubesats was peformed onboard a 3U cubesat STU-2A that was part of a three
satellite constellation built and launched by Shanghai Engineering Centre for Microsatellite (SECM).
The CubeSat MEMS Propulsion Module comprises of four individually controlled thrusters, each
containing a proportional valve and sensors for closed-loop thrust control. The nominal thrust is 1 mN
per thruster. Total mass is 330g including 50g propellant. The size of the module is less than ½ U even
including a control and interface electronics board. Apart from the proportional valve, there are two
additional valves to create independent barriers between each thruster and the propellant tank. It has
the capability of 40Ns total impulse (specific impulse is rated as 81s). The average power consumption
during operation is about 3W.
Since the launch and initial tests of the system, the propulsion system has been activated tested
multiple times. The propulsion system has demonstrated both the ability to raise the orbit of STU-2A
and has also been used to de-spin the spacecraft after and accidental spin up. In this case the spacecraft
was despun from about 65 to 13 deg/s using thrusters, after which magnetic tourqers could be used to
stabilize and fine tune the spin rate. Further details and results from the tests already done and the
upcoming rendezvous with STU-2C will be given in the presentation.
12:00 PM
Canadian Electric Propulsion Development: A Cylindrical Hall Thruster
Carl Pigeon, Nathan Orr, Benoit Larouche, Robert Zee - Space Flight Laboratory, University of Toronto
ABSTRACT
Recent electric propulsion research in the field of Hall Thrusters has developed relatively high thrust
efficiencies in the order of 45-55% for large thrusters of half a kilowatt to a few kilowatts. This
technology has enabled deep space missions and extended station-keeping capabilities. Although
conventional hall thrusters operate efficiently at high power levels, this statement does not hold true
when scaling down for a power and volume constrained microsatellite mission. In order to address this
issue, the traditional Annular Hall Thruster has been modified to have a cylindrical ionization chamber,
thus bearing the name Cylindrical Hall Thruster. The cylindrical ionization chamber configuration
decreases plasma wall interactions in the ionization chamber and has been shown to be more efficient
in lower power operation. To enable more advanced microsatellite missions, the Space Flight Laboratory
(SFL) at the University of Toronto Institute for Aerospace Studies (UTIAS) was contracted by the
Canadian Space Agency to develop a low power electric propulsion system compatible with
microsatellites. The program lead to the development of a SFL's prototype Cylindrical Hall thruster
which has demonstrated the ability to sustain stable operation between 15 - 300 W with an efficiency of
5% - 27% respectively. Test results at the nominal 200 W power level show 6 mN of thrust with a specific
impulse of 1140 s using Xenon propellant. The prototype thruster was initially developed to be
reconfigurable which allowed the parameters such as propellant flow rate, magnetic field and electric
field to be experimentally tuned to find the best configuration. After determining a suitable thruster
configuration for stable thruster operation, a refined protoflight thruster has been developed. By using
permanent magnets instead of electromagnets, a mass savings of 70% was achieved with a thruster
mass of only 450 grams. At 95 mm long and 58 mm in diameter, the thruster was designed to fit in a 1U
CubeSat standard volume will be flight qualified to TRL 6. This paper will present and compare the
performance results using both Xenon and Argon propellant of the prototype and protoflight thruster.
Session VII: Communications
1:15 PM
A Novel Planar Antenna for CubeSats
Jan Verwilligen, Prem Sundaramoorthy - Delft University of Technology
ABSTRACT
The UHF radio amateur band situated around 436 MHz is a very popular radio band for CubeSat
Communications. This band has around 14.5 dB lower path loss compared to the popular S-band due to
the lower frequency. The longer wavelength accompanied with the UHF band results in antennas that
are relatively big compared to the size of a CubeSat. To communicate in this band, CubeSats are
therefore equipped with linear wire antennas in dipole or turnstile configuration. Compared to patch
antennas which are used to communicate in the S-band, these linear wire antennas have the downside
that they need a deployment mechanism. This deployment mechanism increases the risk of failure
during the mission, and subsequently asks more attention during design, integration and testing of the
CubeSat. Furthermore, this system adds extra mass to the CubeSat and it takes up space that could be
used by other subsystems. A novel planar antenna is proposed in this paper that obviates the need for
deployment and meets most of the communication requirements for a CubeSat.
To resolve the issues associated with a wire antenna requiring deployment, research was conducted to
use a patch antenna to communicate in the UHF band. Conventional patch antennas that are resonant
at 436 MHz proved to be too big to integrate in a CubeSat body. The planar inverted F antenna (PIFA)
with it small form factor with respect to the operating frequency was identified as a suitable antenna
choice for CubeSats. The electromagnetic simulation software FEKO has been used to successfully
simulate a PIFA. Results indicate that the antenna is resonant at 436 MHz and fits on a 3U CubeSat body.
The simulated antenna has a low profile height of only 3mm such that it still fits in a CubeSat launch
POD. The radiation pattern is similar to the radiation pattern of a dipole antenna with a maximum gain
of 3.72 dBi and a bandwidth of 2.82MHz is obtained. The use of such a PIFA antenna with no
deployment mechanisms and with potential to be integrated as part of the CubeSat structure, promises
further benefits and opportunities for future CubeSat missions.
1:30 PM
Linkstar, a Globalstar Based Duplex Radio for Satellites In LEO - Architecture and Test Results
Andrew Santangelo - sci_Zone; Paul Skentzos - Space Analytics
ABSTRACT
LinkStar is a full duplex radio system (concurrent uplink and downlink) for satellites in LEO providing
communications coverage to over 50% of the Earth. LinkStar treats the satellite as a secure node on the
internet while it is in orbit and on the ground for testing. LinkStar utilizes the Globalstar satellite radio
network, a constellation of 32 satellites in LEO providing global data and voice services for a range of
uses including oil rigs, shipping containers, gas pipelines and supporting remote communications. Our
research focused on adapting the Globalstar GSP-1720 modem and creating the LinkStar radio
architecture for use in space. Work included marrying the modem with a modified, space rated
BeagleBone Black ARM based computer which utilizes an embedded Linux based operating system to
control the satellite and manage the radio architecture. As part of the radio architecture work also
included the development of an open source flight management system QuickSAT/Vehicle Management
System (VMS) along with the Communicator set of APIs. QuickSAT/VMS is a flexible open source flight
management system tailored for cubesats and other types of small satellites. The architecture provides
for basic satellite command and control, data management, scheduling, event handling and complete
software based radio tool set. The framework allows for users to define custom classes of components
(such as radios, magnetometers and other sensors) without modifying the core architecture. The
architecture provides a robust data management architecture, not only managing the vehicle
configuration and schedule, but also logging system messages, errors and events, and storing data as
needed into separate recording sessions. Communicator is a set of APIs, allowing for the integration of
several radios on one satellite including the LinkStar duplex radio and LinkStar-STX3 simplex radio, Sband radios and many others. Communicator allows the user to add custom modules to the core
architecture, and allows the user to set parameters to define how the radios will work together. Models
show LinkStar will provide up to 50% continuous coverage - both data download AND upload through a
secure internet link. LinkStar radio data is further encrypted to insure the information transmitted to
and from a satellite is secure. In this presentation we will discuss and demonstrate QuickSAT/VMS and
Communicator, and how they work with the LinkStar radio, and the operation and integration of the
LinkStar radio. We will present test results from the lab, UAV based testing, near space testing, and from
the RADSat cubesat mission. In 2016 sci_Zone in partnership the Boeing will be flight testing and
certifying the QuickSAT/Vehicle Management System (VMS) and the LinkStar global communications
radio on the Boeing RADSat satellite. The RADSat Satellite is a 2U CubeSAT that will be deployed from
the International Space Station via the NanoRacks Program. A key piece of this mission is to test and
demonstrate full duplex communications between the satellite and ground via the Globalstar satellite
network utilizing the LinkStar radio architecture. If the satellite is still in orbit, we will present live test
data from the satellite.
1:45 PM
Globalstar Link: From Reentry Altitude and Beyond
Hank Voss, Jeff Dailey, Matt Orvis - NearSpace Launch; Arthur White, Stefan Brandle - Taylor University
ABSTRACT
Three Cubesats flown in the past two years have successfully mapped Globalstar performance over the
altitude range 100 km to 700 km. The Globalstar constellation gives Anywhere and Anytime visibility to
satellites and is ideal for CubeSats, constellations, and formation communication. TSAT (2U) made realtime plasma density and diagnostic measurements in the Extremely Low-Earth Orbit (ELEO) ionospheric
region 350 to 110 km for new in-situ Space Weather mapping. TSAT heated at a rate of 20 degrees /min.
on reentry at 110 km (reentry physics), yet it maintained a good real-time link with ground stations in
Canada and Venezuela. GEARRS1 (3U) was launched from the ISS and verified the Globalstar CDMA
protocol and duplex SMS messaging. GEARRS 2 (3U) was launched with an Atlas rocket on May 20, 2015
into a 350 by 700 km orbit and the simplex modem is still operating well after 8 months (high TLE and
radiation tolerant). Improved global coverage maps of the simplex and duplex performance are
presented. Using a small permanent magnet for attitude control, the two patch antennas (1.616 GHz)
and loss-cone energetic particle detector point up and down the earth's magnetic field lines. The three
SSD detectors mapped the precipitating and trapped particle flux in the aurora zone, the SAMA, the
trapping boundary, and the internal penetrating radiation dose. Several new Globalstar flight radios are
manifested for launch with three axis stabilization so that duplex large file transfer can be characterized.
TSAT and GEARRS data show a strong side lobe link to the 16 radial Globalstar receiver beam
assignments. The possibility for limb contacts with radiation belt satellites (Re<7) appears reasonable.
A linear CubeSat array using the MatLab antenna toolbox demonstrates high gain for Re<7. Line of site
analysis uses STK simulations for polar orbits and limb viewing for MEO and GEO orbits. Data encryption
and hardware options for NSL Globalstar commercial radio processors are discussed.
2:00 PM
Ka-band Technologies for Small Spacecraft Communications via Relays and Direct Data Downlink
James Budinger, Charles Niederhaus, Richard Reinhart, Joseph Downey, Anthony Roberts - NASA Glenn
Research Center
ABSTRACT
As the scientific capabilities and number of small spacecraft missions in the near Earth region increase,
standard yet configurable user spacecraft terminals operating in Ka-band are needed to lower mission
cost and risk and enable significantly higher data return than current UHF or S-band terminals. These
compact Ka-band terminals are intended to operate with both the current and next generation of Kaband relay satellites and via direct data communications with near Earth tracking terminals. This
presentation provides an overview of emerging NASA-sponsored and commercially provided
technologies in software defined radios (SDRs) and transceivers and electronically steered antennas that
will expand the use of NASA's common Ka-band frequencies: 22.55-23.15 GHz for forward data or
uplink; and 25.5-27.0 GHz for return data or downlink. Data rates as high as 100s Mbps are possible via
relays and over 1 Gbps via direct data downlink. Reductions in mass, power and volume come from
integration and software definition of multiple radio functions, operations in Ka-band, high efficiency
amplifiers and receivers, and compact, flat and vibration free electronically steered narrow beam
antennas that cover up to 120 degrees field of regard. One of the technologies described in the
presentation, the software defined near Earth space transceiver (SD-NEST) is intended to be compliant
with NASA's space telecommunications radio system (STRS) standard for communications waveforms
and hardware interoperability.
2:15 PM
Open Source Low-Speed Transceiver Solution for CubeSats
Henry Hallam, Matt Ligon, Kiruthika Devaraj, Alex Ray, Ryan Kingsbury - Planet Labs
ABSTRACT
Over the last 10 years, a number of university-led cubesats have struggled with getting reliable on-orbit
communications for Telemetry Tracking and Control (TT&C). Planet Labs has developed a flight-proven
transceiver radio that we plan to open source to the broader cubesat community. The Planet Labs LowSpeed Transceiver (LST) is a general-purpose, low-cost UHF data radio. The LST employs a 1W
transmitter and provides up to 10 kbps data rate at UHF (400 to 450 MHz), but it is possible to adapt to
other commonly used bands. The LST design can also provide time-of-flight ranging with better than
1km accuracy. Planet Labs has tested the LST on over 100 in-orbit satellites and have been able to
establish connection with most of them on the first pass.
The LST was designed by Planet Labs engineers for use in CubeSats, but is applicable in many other use
cases, e.g., robotics, meteorological balloons, animal tracking, or wherever simplicity and robustness are
desired features. In the form in which we intend it to be released, it does not carry any features specific
to spacecraft use; in particular it does not feature any radiation-hardened or space-rated components,
but rather uses commercially available off-the-shelf parts typically used in commercial electronics. It can
be used on a satellite just as it can be used as part of any remotely-accessed embedded system; we
hope and expect that it will be useful to both the broader cubesat community and for other applications
as mentioned above.
We will be releasing the PCB designs for ground station transceiver and satellite transceiver, in EAGLE
and Gerber format, with the bill of material (BOM), BOM for external ground station components (LNA,
power amp, antenna, rotator), firmware source code, with board support files for the aforementioned
PCBs and development kits, so you can get started before fabbing boards. We will also provide example
host PC programs and user documentation, with PC software for orbit determination using ranging
measurements.
In addition to the LST, we will present the latest data from our compact, low-mass, and low-power highspeed downlink radio (HSD). The HSD is built with COTS parts and operates in X-band with a high gain
spacecraft antenna and a reasonably sized ground station (<5 m antenna aperture on the ground) using
which we have demonstrated ~100 Mbps downlink speeds. This design is capable of providing downlink
throughput in excess of 4 gigabytes during a single 8 minute pass.
2:30 PM
Modulating Retro-Reflector CubeSat Payload operating at 1070 nm for Asymmetric Free-Space Optical
Communications
Jan Stupl, Dayne Kemp, Shang Wu, Dimitriy Arbitman, Julia Tilles, Alberto Guillen Salas - NASA Ames
Research Center; Carlos Rivera de Lucas – ISDEFE
ABSTRACT
Preceding papers submitted to this conference introduced the concept of modulating retroreflectors
(MRR) for free space optical communications. The major advantage of MRRs over conventional laser
communication systems is that they require significantly less pointing accuracy on the spacecraft; typical
values are between a few degrees to 10s of degrees. However, this advantage is bought at the price of
an increased optical power from the ground station on the order of several kilowatts. Lasers capable of
producing these relatively high continuous optical powers are commercially available, but only in a
limited subset of wavelengths, typically ranging from 1.0 to 1.1 microns. Consequently, to take
advantage of these commercially available lasers, MRRs operating in a corresponding wavelength, at
sufficiently high data rates, with an adequate aperture are required. Modulators based on multiple
quantum wells fulfill the latter two requirements but had not been demonstrated in the specified
wavelength range.
In the first part of this paper we describe design, production and testing of a multiple quantum well
MRR that operates at a wavelength of 1070 nm. This wavelength corresponds to that of the popular
Ytterbium doped fiber lasers which are extensively used in laser machining. The second part of the
paper describes the design and testing of driver electronics in a 1U form factor, allowing the MRR to
operate in a cubesat. The driver is versatile and can therefore act either as a communication subsystem
or an independent payload that could be utilized for a technical demonstration of the MRR technology
in space.
Session VIII: Instruments/Science
3:15 PM
Quantum Physics with Cubesats: In-Orbit Observation of Photon Pair Correlations on Board the
Galassia Spacecraft
Rakhitha Chndrasekara, Cliff Cheng, Yue Chuan Tan, Zhongkan Tan - Centre for Quantum Technologies,
NUS; Daniel Oi - University of Strathclyde; Sha Luo, Cher Hiang Goh - National University of Singapore;
Alexander Ling - Centre for Quantum Technologies, NUS
ABSTRACT
The most mature technological path to establishing the most secure form of global quantum
communication networks is to place sources of entangled photons in Earth orbit with satellites. While
optical communications transceivers for ground-to-space communication exist, no space capable source
of entangled photons has been demonstrated.
To raise the technology readiness of the entangled photon systems, we have undertaken a programme
to build and demonstrate entangled photon sources in low Earth orbit. To be cost-effective, we have
decided to use CubeSats which has consequently demanded significant miniaturisation work on the
photon source to fit within the size, weight and power restrictions.
Photon pair sources based on the quantum process of spontaneous parametric down conversion (SPDC)
are the building blocks for quantum-correlated (quantum-entangled) photon pairs necessary for the
most secure form of quantum communication. The first milestone in our programme is to deploy an
SPDC source of photon pairs in space as a pathfinder experiment to demonstrate the principle in the
space and raise the technology readiness level. The first attempt was unsuccessful when the launch
vehicle (CRS Orb-3) failed shortly after take-off, although our compact SPDC source was successfully
recovered intact and found to be fully operational. We are pleased to report that the second attempt
(with a newly built payload) has been successful and the first milestone has been accomplished. The
source was launched on board the Galassia CubeSat (using PSLV C29) to an orbit of approximately 550
km and 15 degrees inclination.
After the satellite was commissioned and the experiment was activated, we observed in-orbit
generation of high quality photon pair correlations (with a contrast of 96 +/- 2%). These results are
compatible with baseline data collected prior to launch and show no degradation. Data will be
presented on the effects of temperature and radiation on the source performance. We will also discuss
how the source was assembled and present plans for upcoming and future missions. The successful
deployment of the first SPDC source in orbit will enable the development of more advanced quantum
light sources capable of testing Bell's Inequality and performing quantum key distribution at space to
ground distances.
3:30 PM
Improving Nanosatellite Imaging with Adaptive Optics
Anne Marinan, Kerri Cahoy – Massachusetts Institute of Technology; John Merk - Aurora Flight Sciences;
Ruslan Belikov, Eduardo Bendek - NASA Ames Research Center
ABSTRACT
Active and adaptive wavefront control is useful on space platforms for a variety of observation
applications. To achieve high contrast imaging to a level of 1 × 10^-10 with a coronagraph (required to
image an Earth-like planet around a Sun-like star), space telescopes require high spatial frequency
wavefront control systems. To achieve intersatellite links through the atmosphere, wavefront correction
is needed to counter the effects of atmospheric turbulence and scintillation. For deployable apertures,
active correction is desired to properly align and calibrate optical systems. Deformable mirrors (DMs)
are a key element of a wavefront control system, as they correct for imperfections, thermal distortions,
and diffraction that would otherwise corrupt the wavefront and ruin the measurement. High-actuator
count mirrors are required to achieve the desired level of correction on space telescopes, but this key
technology lacks spaceflight heritage. The goal of the CubeSat Deformable Mirror (DeMi) technology
demonstration mission is to characterize a microelectromechanical system (MEMS) deformable mirror
and to demonstrate its ability to perform wavefront correction on a nanosatellite platform.
DeMi is a 6U CubeSat that houses a 2U optical payload. The payload is a custom optical bench with a
Boston Micromachines deformable mirror and custom-modified driver electronics that fit within a
CubeSat system. The payload is expected to draw <8 W when enabled. The architecture incorporates
both an external aperture and internal laser diode as well as both a focal place sensor and ShackHartmann wavefront sensor. The remaining volume in the CubeSat is reserved for the supporting bus,
which uses a combination of COTS components and custom interface boards to provide power, pointing
knowledge and control, position knowledge, thermal stability, command and data interface, and
communications.
In this paper, we present the payload design and applications to two major areas: technology
demonstration for next-generation space telescopes, and small satellite intersatellite optical links (for
either communications or laser occultation applications). We also present results from payload
laboratory hardware demonstration and progress towards the flight design and build for this CubeSat
mission.
3:45 PM
SWIMSat: Space Weather and Meteor Impact Monitoring Using a Low Cost 6U CubeSat
Victor Hernandez, Pranay Gankidi, Aman Chandra, Alex Miller, Paul Scowen, Hugh Barnaby, Eric
Adamson, Erik Asphaug, Jekan Thangavelautham - Arizona State University
ABSTRACT
Civilization is growing dependent on knowing the activity of the space environment near Earth, in
particular the activity of the Sun and the impact of near-Earth objects (NEOs). Coronal mass ejections
(CMEs) can have a crippling effect on the networks of satellites used for communication, weather
forecasting, resource monitoring, GPS, and military communications. Astronauts who pave the way
towards permanent lunar settlements and missions to Mars shall rely increasingly on forecasts of solar
activity. Monitoring the Sun for CMEs can lead to timely predictions of energetic particle storms. NEOs
striking Earth are also of great interest to civilians, scientists, the military, and government agencies,
with kiloton-equivalent airbursts occurring once per month and larger events more rarely. While
considerable ground and space assets are devoted to cataloguing NEOs in space, comprehensive
monitoring of airbursts is required to constrain the meter-size end of the distribution, and to reveal
bolide properties and their flux in time and space.
We envision networks of small spacecraft that monitor the Sun for CMEs, and monitor the Earth for
impacting NEOs. CME detection is comparatively straightforward, monitoring the Sun through a
coronographic telescope for bright events. NEO airbursts represent a greater observational challenge.
The flash is a transient lasting a few seconds, while the more persistent feature is the stratospheric dust
trail. The ~0.5-megaton-equivalent fireball above Chelyabinsk in 2013 showed up as long streaks in
weather satellite images. Because such streaks can be confused with other atmospheric transients, the
reliable detection of small NEO airbursts requires the demonstration of autonomous and real time asset
control, long period tracking, and event discrimination and sequencing.
SWIMSat has two goals: (1) monitor solar CMEs, and (2) monitor meter-scale NEO impacts. The basic
feasibility of this approach is demonstrated in networks of small Earth-observing satellites that gather
and process data in real-time. SWIMSat will be located in geostationary or geo-transfer orbit. The
advent of newly available, low-cost CubeSat and rad-tolerant technologies for deep space makes it
feasible to start now, within the scope of the University Nanosatellite Program, and achieve sizable gains
towards the security of near-Earth space within a low cost budget. Using techniques we have developed
to mitigate radiation in a CubeSat for missions to the Moon and to Europa, we shall utilize a combination
of shielding and radiation tolerant, redundant computer and electronics to achieve a long operational
lifetime in space. The science instruments consist of identical rad-tolerant CID cameras, one for Earth
observations and one mounted to a coronagraph for Sun observations. Autonomous feature tracking
will be tested, along with event detection and command. The spacecraft will serve as proof of concept,
leading to a low-cost network of space weather and meteor monitor spacecraft to provide high
resolution coverage from multiple vantage points.
4:00 PM
A Segmented Deployable Primary Mirror for Earth Observation from a Cubesat Platform
Noah Schwarz, David Pearson, Stephen Todd, Andy Vick, David Lunney, Donald MacLeod – United
Kingdom Astronomy Technology Centre
ABSTRACT
The performance of optical imaging systems designed for space applications is often limited by the
volume constraints imposed by the satellite bus. This is particularly the case with the challenging volume
specification of a CubeSat. In these situations the use of deployable optics can provide a way to improve
the performance of the optical system. However the mechanical requirements of optical deployment
mechanisms can be severe and inevitably lead to increases in complexity and cost. This paper presents
the design and test of a 300 mm segmented deployable primary mirror for Earth observation, mounted
within a 1.5U CubeSat volume. The mirror consists of four segments, each with a deployment
repeatability of less than 10 um and the capability for three-degree of freedom adjustment with a
resolution of less than 30 nm. The design presented is a low-cost solution that uses commercial
deployment mechanisms and motors suitable for use in a LEO space environment. This work
demonstrates the feasibility of co-phasing a deployable primary mirror that would provide 1 m ground
resolution from a CubeSat platform.
4:15 PM
The Electron Losses and Fields Investigation
Lydia Bingley, Vassilis Angelopoulos, Ryan Caron - University of California, Los Angeles
ABSTRACT
The Electron Losses and Fields Investigation, or ELFIN, is a 3U+ space weather CubeSat that will be
launching into Earth orbit in 2017. ELFIN got its start in 2012 as a participant in the University
Nanosatellite Program's NS8 round, funded by the AFRL. The mission was then picked up by CSLI/ElaNa
and awarded joint funding from NASA/NSF in 2014, helping provide the push to prepare ELFIN for
development and launch.
The primary goal of the mission is to explore the mechanisms responsible for the loss of relativistic
particles from Earth's magnetosphere by characterizing their properties as they enter the atmosphere.
ELFIN will complete this goal by measuring for the first time the full energy distribution and pitch angle
resolution of precipitating electrons using a UCLA built Energetic Particle Detector. Additionally, ELFIN
will fly a 3-axis Fluxgate Magnetometer to take sensitive measurements of Earth's magnetic field,
allowing for the detection Electromagnetic Ion Cyclotron (EMIC) waves, thought to be the primary
contributor to particle losses. A strategic use of ELFIN data in conjunction with data from equatorial
space weather missions (THEMIS, MMS, etc.) will allow for the development of higher fidelity space
weather models to be used for the protection of ground and space assets.
ELFIN has been secured a ride along with ICEsat 2 to a polar orbit, currently scheduled for launch in Fall
2017. Currently the team is rapidly finalizing designs, performing environmental tests, and executing
component integration in efforts to begin the Flight Model build and get ELFIN ready for delivery.
4:30 PM
The CubeSat Infrared Atmospheric Sounder (CIRAS), Pathfinder for the Earth Observation
NanoSatellite-Infrared (EON-IR)
Thomas Pagano, David Rider, Joao Teixeira. Hartmut Aumann, Mayer Rud - Jet Propulsion Laboratory,
California Institute of Technology; John Pereira, David Furlong, Dan Mamula - National Oceanic and
Atmospheric Administration
ABSTRACT
The CubeSat Infrared Atmospheric Sounder (CIRAS) will measure upwelling infrared radiation of the
Earth in the MWIR region of the spectrum from space on a CubeSat. The observed radiances can be
assimilated into weather forecast models and be used to retrieve lower tropospheric temperature and
water vapor for climate studies. Multiple units can be flown to improve temporal coverage or in
formation to provide new data products including 3D motion vector winds.
CIRAS incorporates three new instrument technologies. The first is a 2D array of High Operating
Temperature Barrier Infrared Detector (HOT-BIRD) material, selected for its high uniformity, low cost,
low noise and higher operating temperatures than traditional materials. The detectors are hybridized to
a commercial ROIC and commercial camera electronics. The second technology is a Lockheed Martin
Coaxial Micro Pulse Tube (MPT) cryocooler. The MPT offers high cooling capacity in a CubeSat
compatible package and its flexure bearing technology enables significantly longer mission life. The
third technology is an MWIR Grating Spectrometer (MGS) designed to provide imaging spectroscopy for
atmospheric sounding in a CubeSat volume. The MGS has no moving parts and is based on heritage
spectrometers including the OCO-2. JPL will also develop the mechanical, electronic and thermal
subsystems for CIRAS. The spacecraft will be a commercially available CubeSat. The integrated system
will be a complete 6U CubeSat capable of measuring temperature and water vapor profiles with good
lower tropospheric sensitivity. The CIRAS is the first step towards the development of an Earth
Observation Nanosatellite Infrared (EON-IR) capable of meeting the replacement needs of the CrIS on
JPSS.
4:45 PM
EXACT: Experiment for X-Ray Characterization and Timing
Ryan Vogt, Lindsay Glesener, Demoz Gebre-Egziabher, Richard Linares, Juliana Vievering, Ilya Zubarev,
Kendra Bergstedt, Charles Denis, Hannah Weiher, Joel Runnels - University of Minnesota
ABSTRACT
The Experiment for X-ray Characterization and Timing (EXACT) is a simple spectrometer designed for the
purpose of measuring hard X-rays (HXRs) from solar flares with high time precision. Solar flares and
coronal mass ejections are the sources of the most extreme space weather events. The plasma and
energetic particles ejected in these events, when Earth-directed, pose radiation risks to spacecraft and
astronauts, and in extreme cases could endanger the Earth's power grid. While the effects of these solar
eruptive events are starting to be well characterized, the acceleration mechanisms for the high-energy
particles produced are not understood.
The EXACT sensor measures bremsstrahlung HXRs from flare-accelerated electron populations to
investigate their origins. The primary objectives of the project are to monitor HXR flares in the declining
phase of Solar Cycle 24 and serve as a pathfinder for a simple, cost-effective HXR spectrometer that will
be a high- energy counterpart to the soft X-ray monitor aboard the GOES set of spacecraft. EXACT will
also perform precise timing studies of solar HXRs to investigate time-of-flight effects of electron beams
and their acceleration site heights, and can perform serendipitous science in conjunction with other Xray observatories.
To achieve these objectives, EXACT is a 3-axis-stabilized, sun-pointed, 3U CubeSat that uses a highenergy radiation sensor with photon time tagging to 1 µs. This high-precision time-tagging will allow the
instrument to serve the additional purpose of testing/demonstrating the concept of spacecraft relative
ranging using gamma-ray burst timing. It is therefore a dual-use sensor that can serve as a relative
position, navigation and timing instrument for GPS/GNSS-denied satellite operations, independent of its
solar purposes.
Due to its simplicity and high time precision, EXACT is a versatile instrument useful for both solar and
astrophysical high-energy sources. EXACT will serve as a pathfinder for a set of CubeSats that can
provide continuous, long-term solar HXR monitoring, and can, with serendipitous co-observations,
perform groundbreaking new science in the study of solar flare-accelerated electrons, helping to
understand the basic generation of the powerful solar sources of space weather.
5:00 PM
Lunar Ice Cube: BIRCHES Payload and the Search for Volatiles with a First Generation Deep Space
CubeSat
Pamela Clark - Jet Propulsion Laboratory, California Institute of Technology; Ben Malphrus - Morehead
State University; Dennis Reuter, Robert MacDowall, David Folta, Terry Hurford, Cliff Brambora, William
Farrell - NASA Goddard Space Flight Center
ABSTRACT
Lunar Ice Cube, a science requirements-driven deep space exploration 6U cubesat mission was select-ed
for a NASA HEOMD NextSTEP slot on the EM1 launch. We are developing a compact broadband IR
instrument for a high priority science application: un-derstanding volatile origin, distribution, and
ongoing processes in the inner solar system. JPL's Lunar Flash-light, and Arizona State University's
LunaH-Map, both also EM1 lunar orbiters, will provide complimentary observations to be used in
understanding volatile dy-namics.
The Lunar Ice Cube mission science focus, led by the JPL science PI, is on enabling broadband spectral
determination of composition and distribution of vola-tiles in regoliths of the Moon and analogous
bodies as a function of time of day, latitude, regolith age and composition and thus enabling
understanding of cur-rent dynamics of volatile sources, sinks, and processes, with implications for
evolutionary origin of volatiles.
Lunar Ice Cube utilizes a versatile GSFC-developed payload: BIRCHES, Broadband InfraRed Compact,
High-resolution Exploration Spectrometer, a miniaturized version of OVIRS on OSIRIS-REx. BIRCHES is a
compact (1.5U, 2 kg, 7W including cryocooler) point spectrometer with a compact cry-ocooled HgCdTe
focal plane array for broadband (1 to 4 micron) measurements, achieving sufficient SNR (>400) and
spectral resolution (10 nm) through the use of a Linear Variable Filter to characterize and distin-guish
important volatiles (water, H2S, NH3, CO2, CH4, OH, organics) and mineral bands. We are also developing compact instrument electronics which can be easily reconfigured to support the instrument in 'imager' mode, once the communication downlink band-width becomes available, and the H1RG family of
fo-cal plane arrays.
Thermal design is critical for the instrument. The compact and efficient Ricor cryocooler is designed to
maintain the detector temperature below 120K. In order to maintain the optical system below 220K, a
special radiator is dedicated to optics alone, in addition to a smaller radiator to maintain a nominal
environ-ment for spacecraft electronics.
The Lunar Ice Cube team is led by Morehead State University, who will provide build, integrate and test
the spacecraft, provide missions operations and ground communication. Propulsion is provided by the
Busek Iodine ion propulsion (BIT-3) engine. Attitude Con-trol will be provided by the Blue Canyon
Technology XB1, which also includes a C&DH 'bus'. C&DH will also be supported, redundantly, by the
Proton 200k Lite and Honeywell DM microprocessor. Onboard communication will be provided by the Xband JPL Iris Radio and dual patch antennas. Ground communi-cation will be provided by the DSN Xband network, particularly the Morehead State University 21-meter substation. Flight Dynamics support,
including trajec-tory design, is provided by GSFC.
Use of a micropropulsion system in a low energy trajectory will allow the spacecraft to achieve the science orbit within a year. The high inclination, equato-rial periapsis orbit will allow coverage of
overlapping swaths, with a 10 km along-track and cross-track foot-print, once every lunar cycle at up to
six different times of day (from dawn to dusk) as the mission progresses during its nominal six month
science mapping period.
5:15 PM
Miniaturized Ion and Neutral Mass Spectrometer for CubeSat Atmospheric Measurements
Marcello Rodriguez, Nikolaos Pachalidis, Sarah Jones, Paulo Uribe NASA Goddard Space Flight Center;
Timothy Cameron - Adnet Systems Inc.
ABSTRACT
To increase the number of single point in-situ measurements of thermosphere and exosphere ion and
neutral composition and density, miniaturized instrumentation is in high demand to take advantage of
the increasing platform opportunities available in the smallsat/cubesat industry. The INMS (Ion-Neutral
Mass Spectrometer) addresses this need by providing simultaneous measurements of both the neutral
and ion environment, essentially providing two instruments in one compact model. The <1.3U volume,
570 gram, 1.8W nominal power INMS instrument makes implementation into cubesat designs (3U and
above) practical and feasible. With high dynamic range (0.1-500eV), mass dynamic range of 1-40amu,
sharp time resolution (>=0.1s), and mass resolution of M/dM=16, the INMS instrument addresses the
atmospheric science needs that otherwise would have required larger more expensive instrumentation.
INMS-v1 (version 1) launched on Exocube (CalPoly 3U cubesat) in 2015 and INMS-v2 (version 2) is
scheduled to launch on Dellingr (GSFC 6U cubesat) in 2017. New versions of INMS are currently being
developed to increase and add measurement capabilities, while maintaining its smallsat/cubesat form.
Alternates
The TechEdSat/PhoneSat Missions for Small Payload Quick Return
Marcus Murbach, Richard Alena, Ali Guarneros Luna- NASA Ames Research Center
ABSTRACT
In 2014, Ames Research Center launched the Technical Educational Satellite 4 (TechEdSat 4) from an
external launcher aboard the International Space Station. This experimental CubeSat deployed an exobrake, an exo-atmospheric drag chute that can be used for controlled de-orbit of a small payload
canister from earth orbit. This capability is useful for returning biological samples from ISS and even
planetary samples from beyond the earth. Such capability can support better biological and medical
science experiments and is a long-term goal of NASA and industry.
The results of the TechEdSat 4 (TES4) mission will be presented along with the design of the follow-on
spacecraft, TechEdSat5/PhoneSat5 (TES5/PS5), which will launch from ISS this summer. The TES4 exobrake deployed, changed the drag on the CubeSat, resulting in early orbital reentry. The time frame for
de-orbit and the quantitative drag assessment from this experiment is very useful for designing future
Small Payload Quick Return (SPQR) methods and spacecraft. The TES5/PS5 features improved GPS
tracking and a modulated exo-brake allowing more precise control of the exo-atmospheric drag and
therefore the re-entry time and location.
The TES5/PS5 is a significant upgrade from TES4, featuring an improved C&DH built around the Intel
Edison mobile computing platform, the core of new PhoneSat. This CubeSat has an ISM-band WiFi
downlink for data, significantly reducing the cost of such communication services. It features multiple
cameras to help verify exo-brake deployment and modulation. The GPS tracking should give precise
orbital trajectories leading to much better drag assessment, re-entry targetting and other benefits.
Development of Green Monopropellant Thruster for LituanicaSAT-2 a 3U CubeSat Mission
Vytenis Buzas, Laurynas Maciulis - NanoAvionics; Liudas Tumonis - Vilnius University
ABSTRACT
The many years of ongoing micro propulsion technology development work at Vilnius University has
culminated with the development of a green monopropellant thruster for CubeSats with a potential for
larger nano or microsatellites as well. The current prototype of micropropulsion unit consists of engine
control unit, redundant fuel feed system with miniature gear pumps for on-orbit pressurization, a
reduction valve, flow control valve, catalyst and thruster capable to produce about 0.5 N of thrust. The
supporting structure fits into the 1.2 U CubeSat form factor. 160 ml of monopropellant blend are stored
in two nitrogen pressurized aluminum fuel tanks and provide approximately 160 m/s of delta V budget
for a 3U CubeSat. The non-toxic fuel does not require any special equipment or infrastructure for
storage and handling while at the same time giving very similar or even better performance as a
worldwide proved Hydrazine monopropellant. The targeted specific impulse is 250 s. The prototype
thruster is currently at TRL 5/6 and is to be flown in space during LituanicaSAT-2 mission which is part of
the QB50 project. Thruster integration and software development is performed by space startup
company NanoAvionics while research and development activities are complemented by leading science
institutes of Lithuania. The presentation will review the challenges and current status of development
following with the case study of using the thruster during the QB50 mission onboard a 3U CubeSat.
Development of the Microwave Radiometer Technology Acceleration (MiRaTA) CubeSat for AllWeather Atmospheric Sounding
Kerri Cahoy, Anne Marinan, Bill Blackwell - Massachusetts Institute of Technology; Rebecca Bishop - The
Aerospace Corporation
ABSTRACT
The Microwave Radiometer Technology Acceleration (MiRaTA) is a 3U CubeSat mission sponsored by
the NASA Earth Science Technology Office (ESTO). The science payload on MiRaTA consists of a tri-band
microwave radiometer and GPS radio occultation (GPSRO) experiment. The microwave radiometer takes
measurements of allweather temperature (V-band, 52-58 GHz), water vapor, and cloud ice (G-band,
175-191 & 207 GHz) to provide key contributions toward improved weather forecasting. The GPSRO
experiment, called the Compact TEC (Total Electron Count)/Atmosphere GPS Sensor (CTAGS) measures
profiles of temperature and pressure in the upper neutral atmosphere and electron density in
the ionosphere. The MiRaTA mission will validate new technologies in both passive microwave
radiometry and GPS radio occultation: (1) new ultra-compact and low-power technology for multichannel and multi-band passive microwave radiometers, and (2) new GPS receiver and patch antenna
array technology for both neutral atmosphere and ionospheric GPS radio occultation retrieval on a
nanosatellite. In addition, MiRaTA will test (3) a new approach to spaceborne microwave radiometer
calibration using adjacent GPSRO measurements.
AIM-PALS - ESA CubeSats Designed for Unique Science in a Dual Asteroid System
Emil Vinterhav - ÅAC Microtec; Jan-Erik Wahlund - Swedish Institute of Space Physics
ABSTRACT
The interest for for small satellites including CubeSats is currently growing very rapidly as their potential
as platforms for carrying advanced payloads and supporting advanced missions becomes more and
more established. CubeSats in particular have gone through a remarkable change in status from the
most simple of simple spacecraft platforms often overlooked by established stakeholders to being
widely accepted as a capable vehicle for carrying out complex missions with advanced payloads.
In AIM-PALS a group of world leading planetary and asteroid scientists from the Swedish Institute of
Space Physics, the Institute of Space Sciences in Spain and the Royal Institute of Technology in Sweden
have designed a deep space exploration mission where the unique capabilities of two 3U CubeSats are
exploited to the limits in order to obtain close range measurements of the two planetesimals
constituting the Didymos binary asteroid system. The Cubesats that carry two imagers, a magnetometer
and a mass spectrometer between them will be carried to the Didymos system by the ESA AIM (Asteroid
Impact Mission) where they are deployed for proximity operations in the asteroid sphere of influence.
The spacecraft will operate closer the planetesimals than the AIM spacecraft can. The nominal mission
timeline stretches three months from deployment to a possible soft landing and involves a high
resolution mapping of the lesser planetesimal, observation of the NASA DART (Dual Asteroid Redirect
Test) impact from second and third vantage points, measurements on the ejecta from the impact,
transfer to the main planetesimal of the system and a final touch down on the latter. A successful AIMPALS mission will enhance our understanding of the asteroids in general and Didymos in particular
significantly.
The complexity of the mission stemming from the advanced and diverse payloads as well as operating at
far ranges from the Earth inside the sphere of influence of a low gravity system places challenges on the
system design that CubeSat designs have yet to be proven for. The AIM-PALS spacecraft are designed for
high autonomy and high reliability by ÅAC Microtec with a preference for COTS equipment but with
access to state of the art packaging technology where minimum form factor and high reliability avionics
are necessary. The spacecraft will communicate with Earth through the AIM spacecraft and possibly also
use the main spacecraft for positioning in the dual asteroid system. The DLR, the German Space Agency
are responsible for mission analysis and for preparing a conceptual attitude and orbit control system
design that can operate the spacecraft in the challenging environment of the weak gravity from two
planetesimials locked in a not well defined orbit around one and other. The paper presents the mission
outline, mission analysis and the system design to some detail.
Keep it Simple. Make it Bigger?
Eric Bertels, Adrien Palun, Benoit Chamot, Zeger de Groot, Jeroen Rotteveel - Innovative Solutions In
Space BV
ABSTRACT
Size and mass have always been adversaries of spacecraft designers. Engineers are always trying to get
rid of the last grams in order to avoid the cost of launching heavy spacecraft or fit more performance
within the launch capacity available. In the world of CubeSats, this tendency still exists even though a
CubeSat is about as small and light as you can make a fully functional spacecraft. While the developers
have understood the limitation of the 1-Unit form factor and move towards larger form factors such as
the 3-Unit CubeSat, there is always a fear to scale up to a bigger spacecraft bus as it looks like it would
certainly result in being too expensive. The first reason is not to "betray the CubeSat philosophy":
making things as small as possible and forcing themselves to "think inside the box". The second reason is
the belief that a larger satellite will always result in a more expensive project, mainly due to the increase
of the launch fee. Last but not least, developers may feel that a larger satellite will mean a more
complex project.
As a result, developers have put constraints on their design to make sure that their new complex
payload and supporting platform system are adapted for the limited mass, volume and power budgets.
It turns out a large amount of engineering hours are spent on miniaturising existing systems and making
everything fit, ultimately becoming much more significant than the additional cost needed to launch a
bigger platform. This often results in adding complexity on a satellite which leads to higher cost, longer
development times, and increased risk. This goes against the "cheaper and faster" approach promoted
by the CubeSat community, only to satisfy the urge to keep things small.
This study aims at formalizing the trade-off between the complexity of a CubeSat (need for deployable
panels, complex mechanical design, highly integrated electronics, accommodating optics, etc.), its
performance, and all the costs related to the project (development, manufacturing and launch).
Different use cases, inspired by real missions, will be presented. The paper will focus on satellites
designed for LEO and explore three different missions: Earth imaging, technological demonstrators, and
educational projects. Both one-off's and missions consisting of multiple satellites will be considered.
The paper will also describe the consequences of moving to a larger platform. These include improved
ADCS capabilities, ease of integration of the subsystems as well as possible extension of the mission's
objectives. This analysis and the presented trade-off will allow the discovery and formal definition of the
tipping points between the major CubeSats formats (1U, 3U, 6U and 12U) and to address possible sweet
spots in satellite size versus mission objectives to be achieved, taken from a life cycle cost approach. The
authors also hope that it will enable the CubeSat community to evolve towards even more capable, and
yet cheaper, systems.
Patch Antennas on Composite Printed Circuit Broads for Space Applications
Chunwei Min, Nick Howland, Nick Potts - Printech Circuit Laboratories
ABSTRACT
Patch antennas are commonly used in space applications. They are typically fabricated on fibre-glass
reinforced (FR) or polytetrafluoroethylene (PTFE) -based laminates using standard printed circuit board
(PCB) process. This work investigates the characteristics of the antenna of this type on composite PCB in
terms of manufacturing techniques and tolerances, mechanical and thermal performance. The objective
is to validate that the designs are capable of offering stable radiating characteristics, whilst providing
high structural strength with low mass. The results are compared with the ones on conventional builds,
and have demonstrated attractive properties that are suitable for applications in space.
Reinforcements with higher relative dielectric constant (Dk) are usually needed to offer adequate
mechanical strength for rigid laminates. This degrades radiation efficiency of patch antennas due to the
fact that less fringing fields can be coupled to the space. The use of low-Dk materials may be
unavoidable for applications where antenna designs with either high gain or broadband is required.
Nevertheless, low-Dk materials are, in many cases, soft and structurally weak, and may deform when
bonded into PCBs, resulting in lower tolerance and higher risk of failure. The composite PCB is therefore
introduced to address the trade-offs to ensure an efficient design with adequate mechanical strength.
One reliable configuration is the integration of Nomex honeycomb and PCBs. The Nomex honeycomb is
made of resin-infused fibre papers, and formed into honeycomb structure. Given the mechanical
requirements, cavities of the structure can be either filled with resin, or left as hollow with air when
bonded with other reinforcements. Patterns can be deposited on standard PCBs for planar designs, or
flexible ones for conformal structures. Antenna design requirements, such as miniaturisation, bandwidth
enhancement, gain improvement, polarisation control, mutual coupling reduction, can be achieved
using the proposed configuration. The antenna can be readily integrated with 3D conformal structures,
such as radomes, polarisers and high-impedance surfaces into a single module for various requirements
and applications.
In this work, a series of patch antennas are built using air-filled honeycomb and flexible PCBs to
investigate their performance at GPS, GLONASS and S-bands. The antennas are fabricated on both PTFE
laminates and the proposed configuration with a ground plane of 90mm x 90mm. The measured results
of both builds are compared, and some improvements are noted. It is found that the operable
impedance bandwidth is improved by 3% from the design of single patch. Improvement of peak gain by
2dB is noted at boresight. The design on composite build is considerably light weight with 75% reduction
on mass, yet providing rigidity and good thermal strength, which lends itself rather suitable for the
application. Detailed results and discussions will be, if accepted, included and given in the presentation.
Thermal Analyses Results of the PICASSO CubeSat
Lionel Jacques, Lucas Salvador, Laurence Rossi - University of Liège
ABSTRACT
PICASSO is a CubeSat project led by the Belgian Institute for Aeronomy (BISA) and the European Space
Agency (ESA), in partnership with Clyde Space Ltd and the VTT Technical Research Centre of Finland Ltd.
The objective of this triple-unit CubeSat is to demonstrate low-cost science opportunities through the
utilisation of CubeSat technology. PICASSO comprises two scientific payloads: VISION, a visible and nearinfrared hyper-spectral imager and SLP, a Sweeping Langmuir Probe. While SLP continuously gather data
to study the ionosphere, VISION payload only operates 3min at sunrise and sunset (eclipse entry and
exit points) by looking at the Sun through the atmosphere to retrieve stratospheric ozone and
temperature vertical profile.
This paper is about the thermal analysis of the CubeSat. The CubeSat will be in a circular low Earth orbit
between 450km and 670km to respect the 25 years space-debris mitigation guideline. Its attitude is
mostly sun-pointing with a 1 arcdeg accuracy, dictated by the VISION payload. This attitude strongly
drives the thermal behaviour of the CubeSat, exposing only its smallest cross section to the Sun. The
second major driver is the requirement of the SLP payload to have a conductive gold coating over most
of the external surface of the spacecraft platform and solar panels. A particular attention is drawn to the
modelling of the VISION payload with its Fabry-Perot interferometer and entrance filter stack, the latter
being directly exposed to the Sun.
The analysis is conducted under the European Space Agency thermal analysis software ESATAN-TMS and
the model is composed of more than 3000 nodes. The standard worst (hot and cold) case approach is
followed and an uncertainty analysis is performed taking into account major parameters such as contact
conductances, heat dissipation, radiative links, specific heat... The paper will present the model,
assumptions and reflect the results and conclusions of the thermal analyses.