Project “Wall-Eagle”
CDR

Rocket Model

Detailed Sections

Mass Estimates
Section
Structure
Supporting Equipment
Electronics
Recovery
Motor
Total
Mass Growth
Mass Allowance
Mass (lb.)
8.577
9.444
1.5
2.516
6.47
28.5
3.7
32.2
Percentage of Total Weight
33.58%
31.47%
5.00%
8.39%
21.56%
N/A
12.98%
113%

Ogive Nose Cone
• Low Coefficient of Drag
• Easy to manufacture
• Rated highest by team trade study
• Commonly used in professional and hobby rocketry

Nose cone dimensions

Trapezoidal Fin
• Very easy to manufacture
• Less drag than clipped delta fins, more than elliptical fins
• Quicker stabilization than elliptical fins and clipped delta fins.

Fin Dimensions

Internal bays
• Payload Bay
• Ballast Tank
• Avionics Bay
• Motor Section

Stability
• Center of Gravity: 49.22 inches from nose tip
• Center of Pressure: 61.26 inches from nose tip
• Stability: 2.29 calibers
• Calculations given from OpenRocket
• Mass additions are expected to be added forward of CG

Stability margin before apogee
3,5
3
2,5
2
1,5
1
0,5
0
0 2 4 6 8
Time (seconds)
10 12 14 16

Motor Selection / Altitude Prediction
• Initial Motor selection is the Aero K960-P
▫ R-P: Loki White, Plugged
• Initial thrust-to-weight ratio above required 5:1
• Achieves above average thrust within ¼ second
• High initial thrust provides high stability off the rail

K960-P Thrust curve

Thrust-to-weight
12
10
8
6
16
14
4
2
0
0 0,2 0,4 0,6 0,8 1
Time Seconds
1,2 1,4 1,6 1,8 2

Motor Selection/Altitude Prediction
• Maximum altitude achieved 3395 feet
• Mass increase of 12.97% altitude gives a projected 3045 feet
• Assumptions include smooth construction and
5 mph winds
• Mass increase of 25% would not allow rocket to reach desired altitude

K960-P Altitude vs. Time
Figure 1.3: Altitude vs. Time K780R-P

K960-P Motor Specifications
Manufacturer
Motor Designation
Diameter
Length
Impulse
Total Motor Weight
Loki Research
K960-P
2.13 inches
19.6 inches
1949 N-sec
3.85 lbm
Propellant Weight
Propellant Type
Average Thrust
Maximum Thrust
Burn Time
2.05 lbm
Loki White
225 Pounds
345 Pounds
1.95 sec

Overview

Parachutes
• Three parachutes required
▫ Drogue – 20 inches*
▫ Main – 140 inches*
▫ Payload – 36 inches*
* Estimates using standard round parachute without spillholes.

Parachutes
• Construction
▫ Shape
 Semi-ellipsoidal
 No spill hole

Electronics
• Avionics bay
▫ Two altimeters
 Altus Metrum Telemetrum
 PerfectFlite StratoLogger

Attachments
• Fasteners
▫ Nylon Slotted Pan Head Machine Screws
▫ Steel U-Bolts
▫ Quick Links

Parachute Materials
• The parachute will be made of Ripstop nylon
• Ripstop’s tear resistant weaving is ideal for parachute making

Shock Cord Material
• The shock cord will be made of
1” tubular nylon
• 1” tubular nylon has excellent tensile properties
• A vendor has already been secured
• The Auburn team has worked with this material before

CO
2
Ejection System
• Increased safety
• More reliable at high altitudes
• Reduced risk of equipment damage

Commercial Systems
• Available from Rouse Tech and Tinder rocketry
• Viability of CO
2 systems repeatedly demonstrated in the field
• A single 12g cartridge is recommended for a 5” diameter rocket with sections up to 22” long.

Custom Designed System
• E-match ignites small Pyrodex charge
• Charge pushes cartridge against spring into an opening pin
• Cartridge is punctured and quickly releases CO
2
• Section is pressurized with enough force to separate rocket and deploy parachutes

Custom Designed System
• Each system contains three
CO
2 cartridges
• Each cartridge is separately controlled
• Dual fault tolerance

Ejection System Implementation
• Two ejection systems total mounted outside the avionics bay
• One system deploys drogue parachute and ejects payload bay
•
• Second system deploys main parachute
Two altimeters, each controls two CO system
2 cartridges on each

Subscale Plans
• Phoenix Missile Works-
▫ Sylacauga AL, January 11th
• Sizing: 80%
• Motor: J-425
▫ Total Impulse: 152 lbs-s
• Length: 68 inches

Flight Predictions
• Stability Caliber: 1.89
• Altitude: 2926 ft
• Drift: 1000 ft with 5mph winds
• Recovery
▫ Drogue at Apogee
▫ Main Deploy 900 ft.
▫ Backup for 700 ft.

Flight Data
• Altitude Achieved: 3600 ft.
• Stability: Visually very stable
• Main Deploy failure.
▫ Probable cause: Additional friction between nose cone and body.
▫ Damage sustained: Minimal
• Second Subscale Flight Planned
▫ January 31st

Overall Final Design

AGSE Design Overview

Launch Pad Box Dimensions

Payload Hatch Function
• Seals payload bay during flight
• Hatch opens and closes autonomously with a microservo
• Must be closed autonomously
• Guides robotic arm into payload bay

Payload Access Plate and Positioning
• Single access plate revolves on slightly tightened hinges
• Hinge operates with microservo
• Will allow remote opening and closing
• Will resist loose swiveling, but may be easily closed and locked using small force
• Optical markers to guide robotic arm

Payload Hatch Closing Process
• Robotic arm will reach over the rocket to push the door closed
• The arm will press down with enough force to latch the door shut
• The latch will be a simple mechanical lock mounted inside the mold line
• Edges of door sealed with rubber sealant

Modified CrustCrawler AX-12A Smart
Robotic Arm
• ~29” maximum reach
(nearly 7-inch extension)
• 5 degrees of freedom
• Most value and capabilities for the price
• Completely customizable
• Price - $830
• Infrared sensors installed
• Modified gripper

Key Design Features
•
Our modified design lifts 2+ pounds
•
Fully ROS,MATLAB,LABVIEW Compatible!
• Rugged, all aluminum construction for maximum kinematic accuracy
(1mm - 3mm)
• Hard Anodized finish for maximum scratch and corrosion resistance
•
The gripper will use pressure feedback to verify capture of payload
• Full control over position (300 degrees), speed, and torque in 1024 increments
•
Sensor engineered gripper design includes IR sensors to scan ground and ensure mission success
•
Can grip with three points of contact
•
Minimal moving parts as robot arm can reach to close and latch door

Robot Arm Gripper Requirements
• Able to hold cylindrical payload
• Support 4 oz. weight
• Reach ground/reach payload bay
• Able to rotate at the wrist
• Able to sense that payload has been obtained
• The Big Grip Kit from the CrustCrawler AX-12A series robotic arms meet criteria plus more

IR Sensors
• Affixed to front of grabber, scans dark ground
(grass/dirt) for light surface (payload).
• Arm engages payload once detected.
• If payload dropped, search and capture of the payload may be repeated until mission success

IR Sensors Payload Detection and
Orientation

Contingency: Preprogrammed Location
• Use preprogrammed location of payload in case
IR sensors plan doesn’t work out
• Can choose location of payload, so static coordinates suffice
• Easier, but will cause launch failure if payload dropped

AGSE Truss
• Constructed out of durable carbon fiber
• Designed to support the full weight of the rocket
• Connected to two metal wires at top of truss
• Rotates from horizontal to 85° via winch
• Returns to horizontal after rocket launch

AGSE Truss
• Bottom is counterweighted to ease lifting
• Measurements ensure bottom does not contact the ground
• Rocket attached to truss via slotted rails
• Attachment rails double as launch rails ensuring launch stability
• Truss will lock in vertical position once erect via winch system and blast plate

AGSE Truss
• In launch position, blast shield protects sensitive components
• Igniter insertion system extends into motor
• Rocket is then ready for inspection

Igniter Insertion System
• Toothed insertion system
• DC electric motor drives the tooth extender into the mast
• Initiated with a program that is linked to the
AGSE controller

Igniter Insertion System
• Located 6-8 inches below the base of the rocket.
• Main motor is protected by the blast plate
• Rise through a whole in the blast plate to access the rocket

Igniter Insertion System
• Extension of 26.6 inches
• Igniter pause at full extension
• E-match attached to tip of the insertion system is in contact with motor
• Inspection and arming of the rocket
• Countdown ensues, followed by blast off
• Dowel diameter will not choke motor

Igniter Inserter System

Master Microcontroller
• Single microcontroller drives all AGSE functions
▫ Simplifies design
▫ Minimizes risk
▫ Eliminates communication between multiple microcontrollers
• Arduino mega used

Electrical Schematic for AGSE

Launch Controller

Subsystem Connectivity
• All autonomous systems connected through microcontroller
▫ Only launch controller handled independently
• Single start, pause, and reset switches

Nominal AGSE Process
• Start command received
• Robotic arms commanded to find payload
• Arm deposits payload in rocket
• Payload bay hatch closes
• Launch rail raised
• Igniter inserted
• Sequence pauses
• Launch button depressed
• Rocket launches

AGSE Flow Chart
• System inspected prior to launch
• In some cases it is possible to reset and re-run sequence in an error has occurred

Risks
• Power Failure
• Programming Errors
• Equipment Assembly Errors
• Component Synchronization
Failure
• Sequence exceeds allotted time
(10 minutes)
• System unresponsive
• Damage from environment
(humidity, rain)

Test Plans
• Full system test (normal conditions)
• Speed test for winching system
• Off-design payload configuration
• Partially drained batteries
• Power failure during AGSE sequence
• Dropped payload

Matthew Austin Phillips
Safety Officer
Auburn University Student
Launch

Environmental Effects
• AGSE
▫ Humidity
▫ Radio Interference
• Airframe
▫ Weather
▫ Fire hazard
• Recovery
▫ Weather
▫ Fire Hazard
• Outreach
▫ Weather
▫ Fire Hazard
▫ Lost Rockets

Other Additions
• Updated risks and mitigations
• Operators manuals
• Test equipment sign-out sheets
• Materials sign-out sheets
• Standard Operating
Guidelines
• MSDS
• NAR Regulations

7 th Grade Rocket Week
Students Learn About:
• Gravity and g-forces
• Newton’s Laws of Motion
• Elementary rocketry
• Science, technology, engineering, and mathematics
• Teamwork and communication

7 th Grade Rocket Week
Students Work Hands-On:
• Assembling an Alpha rocket in teams of 2-3
• Sanding, gluing, and painting rockets
• Initiating and observing rocket launches

Educational Outreach Programs
• Auburn Junior High School/Auburn High School Rocket Team
▫ Mentor team to compete in Team America Rocketry Challenge
▫ Teach students design and technical writing methods
▫ Provide facilities and equipment for team use
• Boy Scout Merit Badge University
▫ Teach troops about space exploration
▫ Supervise Alpha rocket assembly
▫ Award Space Exploration Merit Badge

Educational Outreach Programs
• Tuskegee Airmen National Historic Site Field Trip
▫ Guide Drake Middle School students on half-day field trip
• Samuel Ginn College of Engineering E-Day
▫ Present AURA and Student Launch teams to prospective students
• AURA Movie Night Event
▫ Show Apollo 13 at Tiger 13 Cinemas
▫ Provide Q&A with engineers and students

Additional Information
• Budget Summary
• Timeline Summary