Payload Design Criteria for the
Space Test Program
Standard Interface Vehicle
(STP-SIV)
Mr. Mike Marlow
STP-SIV Program Manager
National Science Foundation Workshop on Small Satellite
Missions for Space Weather and Atmospheric Research
Purpose
 Mission Capabilities Of The STP-SIV Spacecraft
 Standard Spacecraft To Payload Interfaces
 Top-level Detail To Determine If STP-SIV Is A Candidate
For Your Mission
National Science Foundation Workshop on Small Satellite Missions for Space Weather and Atmospheric Research
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STP-SIV Road Map
2005
SERB Payload Analysis
Concept Definition
2007
2009
2011
2013
Requirements Definition
Industry Briefings
Source Selection Documentation
Source Selection
1 Apr 06
SIV Delivery Order #1 (STPSat-2)
Payload, LV Determination
S/C and S/V Development & Test
DO#2 (STPSat-3)
DO#3 (STPSat-4)
DO#4 (STPSat-5)
1 Apr 12
DO# 2 buy long leads at ATP
DO# 3 long leads on shelf
DO#4 S/C Pre-assembled
Last Order Date
National Science Foundation Workshop on Small Satellite Missions for Space Weather and Atmospheric Research
3
Spacecraft Capability
Orbit Altitude
Orbit Inclination
Launch Mass
SV Stored Volume (cm)
Reliability (at 7 months)
Stabilization Method
Pointing Modes
Attitude Knowledge
Attitude Control
Bus Voltage
Comm Frequency
Command Rate
Telemetry Rate
Data Storage
Payload Volume
Payload Mass
400 – 850 km
0° – 98.8°
≤ 180 kg (ESPA driven)
60.9 x 71.1 x 96.5 (ESPA driven)
0.90
3-axis
Nadir, Sun Pointing, Safe
0.03° 3σ (goal 0.02° 3σ)
0.1° 3σ (goal 0.03° 3σ) +Z
28 V ±6
SGLS
2 kbps uplink
2 Mbps downlink
8 Gbits
0.14m3
60 kg
+X
National Science Foundation Workshop on Small Satellite Missions for Space Weather and Atmospheric Research
+Y
4
Launch Vehicle Compatibility
Falcon 1
Minotaur I
Minotaur IV
Pegasus/Raptor
EELV Secondary Payload Adaptor (ESPA)
[Atlas and Delta]
National Science Foundation Workshop on Small Satellite Missions for Space Weather and Atmospheric Research
5
Spacecraft Design
Sample Payload Configurations
2 fixed/deployed arrays
1 gimbaled array
GaAs UTJ solar cells
30 A-hr Li Ion battery
Payload Volume
Payload Interface Panel
Star tracker
Silver Teflon Coated Radiator
Rigid LV Interface Panel
1 Star Tracker, 1 magnetometer
6 sun sensors, 1 GPS receiver,
3 reaction wheels, 3 torque rods
National Science Foundation Workshop on Small Satellite Missions for Space Weather and Atmospheric Research
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Topside Sounder Concept on STP-SIV
 Configuration above shows four deployed 4-m antennas on all
four corners of the STP-SIV spacecraft
 This effectively yields two, crossed 8-m dipole antennas
National Science Foundation Workshop on Small Satellite Missions for Space Weather and Atmospheric Research
7
Spacecraft to Payload Interfaces
Mechanical
• 1” grid aluminum panel
• #10 fasteners
• Stringent environment
Thermal
• Coupled Heat Transfer
• Plate temperatures: -20o to +50o C
• 100 Watts Heat Rejection
Power
• 100 Watts Orbit Average
• 28 V ±6
EMI
• Case by Case
• System Test
on each mission
Data
• Up to 2 Mbps data rate
• RS-422 Command and Telemetry
• Synchronous data transmission
• 8 Bi-Level Discreet I/O channels
• 8 analog channels/payload
National Science Foundation Workshop on Small Satellite Missions for Space Weather and Atmospheric Research
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Feasibility Study
 Payload to spacecraft
compatibility
 Payload to payload
compatibility
 Identifies potential
risks
 ROM estimate to
integrate, test and
operate
National Science Foundation Workshop on Small Satellite Missions for Space Weather and Atmospheric Research
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Opportunities
 Enables space weather communities to leverage
S&T spaceflight opportunities
 Share SIV payload space
 Rideshare S&T launch opportunities
ESPA on every EELV, payload adaptors on Minotaurs I & IV
 Provides cost-effective platform to demo payloads
and systems to support space weather programs
 Basis for follow-on programs
 Larger spacecraft class
 Use of spacecraft to payload “standard” interfaces
National Science Foundation Workshop on Small Satellite Missions for Space Weather and Atmospheric Research
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Summary
 SIV is a change from past STP business practices
 Moving away from “one-of-a-kind” spacecraft to gain
benefits of successive spacecraft builds
 More responsive IDIQ contract, fits with other Space
Development & Test Wing IDIQs
 Planned to provide improved access to space for
SERB S&T payloads
 Potential benefits for broader space community
National Science Foundation Workshop on Small Satellite Missions for Space Weather and Atmospheric Research
11
Payload Design Criteria for the
Space Test Program
Standard Interface Vehicle
(STP-SIV)
Mr. Mike Marlow
STP-SIV Program Manager
National Science Foundation Workshop on Small Satellite
Missions for Space Weather and Atmospheric Research 12
National Science Foundation Workshop on Small Satellite Missions for Space Weather and Atmospheric Research
Standard Payload to Spacecraft Interfaces
 Power
M
Spacecraft
T
Payload
P
1
D
Payload
2
 Mechanical
 Fasten payload hardware to
spacecraft structure
 Align payload hardware to
spacecraft reference
 Thermal
 Sense temperature at payload to
spacecraft interface
 Control temperature at payload
to spacecraft interface by
affecting spacecraft side
 Supply primary main electrical
power to payload
 Supply redundant main payload
power
 Supply power for payload heaters
 Data
 Supply bilevel discrete signal from
spacecraft to payload for reset or
other switching functions
 Provide command data from
spacecraft to payload
 Provide data transfer from
spacecraft to payload (code upload,
time synch, attitude, GPS)
 Provide digital telemetry data from
payload to spacecraft
 Provide analog data from payload to
spacecraft (state of health
monitoring)
National Science Foundation Workshop on Small Satellite Missions for Space Weather and Atmospheric Research
13
STP Rideshare Opportunities
FY06
FY07
FY08
FY09
FY10
FY11
FY12
FY13
1Q 2Q 3Q 4Q 1Q 2Q 3Q 4Q 1Q 2Q 3Q 4Q 1Q 2Q 3Q 4Q 1Q 2Q 3Q 4Q 1Q 2Q 3Q 4Q 1Q 2Q 3Q 4Q 1Q 2Q 3Q 4Q
FY09 Minotaur IV Jan 06
PL Selection
Development
Mission Integr
Launch
DMSP F-19
Oct 05
SPL Selection
Special Studies*
Mission Unique
Mission Integr
Launch
STP-2
Apr 06
SPL Selection
Special Studies*
Mission Unique
Mission Integr
Launch
FY11 Minotaur
PL Selection
Mission Integr
Launch
DMSP F-20
SPL Selection
Special Studies*
Mission Unique
Mission Integr
Launch
FY13 Minotaur
PL Selection
Mission Integr
Launch
There are potentially 30 ESPA-class
spacecraft rideshare opportunities
between FY09 – FY13
Oct 08
Apr 08
Oct 10
National Science Foundation Workshop on Small Satellite Missions for Space Weather and Atmospheric Research
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