Mission Goals

• Achieve 10,000ft +/- 10%
• In-field integration time for the rocket is less than 60 minutes
• FEA shall be performed for all bulkheads, thrust plate, and motor retainer and all must  have a safety factor >3
• ​Thrust-to-weight-ratio be greater than 10
• Manufacture a completely SRAD airframe using composite materials (barring couplers and rail guides)
  
• Maximize the number of SRAD components, including composites and machined parts
  
• ​Motor securing mechanism shall be fastened in under one minute
  

ESRA Requirements

• Thrust-to-weight ratio shall be calculated based on the average thrust of the motor during the first 1 second of operation divided by the takeoff weight of the rocket (min 5:1)
• Launch vehicles shall be adequately vented to prevent internal pressures developing during flight and causing either damage to the airframe or any other unplanned configuration changes.
• Launch vehicles shall be constructed to withstand the operating stresses and retain structural integrity under the conditions encountered during handling and transportation and during rocket flight.
• Teams shall ensure that the fin flutter velocity of the rocket is at least 50% higher than the maximum expected rocket velocity.
• Rockets shall be built using lightweight materials, e.g., fiberglass and carbon fiber, or when necessary ductile lightweight metals, e.g., aluminum, and construction techniques suitable for the planned flight.
• Joints shall be designed such that the coupling tube extends no less than 1 body tube diameter (1 caliber) into the airframe section from which the coupler will separate during flight. (Airframe-to-coupler sliding joints intended to separate during a recovery event)
• ​Joints shall be designed such that the coupler tube extends into the nose cone / boat tail / transition-to-coupler to the lesser of 1 body tube diameter (1 caliber) or the maximum depth possible for said design. (nose cone / boat tail / transition-to-coupler intended to separate during a recovery event)
• Joints shall be designed such that the coupling tube extends into the mating component to the lesser of 1 body tube diameter (1 caliber) or the maximum depth possible by the design of the mating component. (Joints not intended to separate during flight)
  
• Joints shall be affixed by mechanical fasteners and/or permanent adhesive. (Joints not intended to separate during flight)
  
• Regardless of implementation airframe joints shall prevent bending.
  
•  A minimum of two rail buttons shall be used, reinforced into airframe with a metallic fastener, support the weight of the rocket on the rail, and not block access to arming holes. Fly-away / 3D printed rail guides are not permitted.
  
• A rail departure velocity of at least 30 m/s (100 ft/s) is required. If 30 m/s is unable to be met, stability must be proven by detailed analysis or test, provided it is greater than 15 m/s.
  
• Launch vehicles shall maintain a dynamic stability margin of at least 1.5 body calibers, regardless of dynamic changes to mass or center of pressure, to apogee.
  
• Launch vehicles shall not be “over-stable” during their ascent, defined as having a static stability margin >4 calibers or a dynamic stability margin during flight >6 calibers.​

Structure

Nose Cone:

• Fiberglass layup in a 3D-printed clamshell mol
• ​Fiberglass selected for radio transparency reasons
• Uses a tangent ogive design (26” tall & 6.3” diameter
• ​COTS Coupler Section (12”)
• Removable clover bulkhead allows for addition of weights & recovery beacon inside nose cone​​
• ​Threaded rod extended to span entire nose cone to increase rigidity

​

Clover Bulkhead

• Provides mounting point for recovery hardware in the nose cone (U-Bolt).
• Allows for the beacon and weights in the nose cone to be accessed
• Machined out of 6061 T6 Aluminum

Booster Bulkhead

• Transfers snatch force from main chute to booster tube
• ​Weight-reduced
• Machined from 6061 T6 aluminum
• ​3-spar design to increase mounting area (cameras, trackers)
• Epoxied to booster tube
• ​Similar to past designs, utilizing a thin membrane and spars for a combination of weight reduction and strength

Top AV Bulkhead

• Transfers the snatch force from main chute / drogue through AV bay
• ​Machined from 6061 aluminum
• Attached to AV bay structure
• Not epoxied to coupler tube
• Symmetry for threaded rods
• Upper bulkhead - fastened to threaded rods (removable)
• Added thermal mass

Bottom AV Bulkhead

• Transfers the snatch force from main chute / drogue through AV bay
• Epoxied to rocket coupler tube
• Machined from 6061 aluminum
• Weight-reduced
• 4-spar design (symmetry for threaded rods)
• Lower bulkhead - fastened to threaded rods & epoxied to coupler tube

​

Fin Structure

• 4 x trapezoidal fins
• 3/16” carbon fiber plate from DragonPlate
• ​Dimensions optimized using custom MATLAB script with OpenRocket integration
• Will be optimized again after component manufacturing
• Integrated fin tab with slots for fin support structure
• ​Cut on SHED waterjet

Fin Support Structure

• Interlocking structure made with ¼” carbon fiber sheets
• Fin tabs slot between vertical bars
• Machined using water jet in SHED, cut from DragonPlate supplied carbon fiber
• ​Assembled using plywood laser cut jig

Avionics

• Flight Computer
• RRC3 Classic Altimeters
• Powered by a 7.4V 500mAh battery

COTS Trackers

• Featherweight GPS Tracker
  • Powered by a 3.7V 4400mAh battery
  • Range tested to 3.77 miles LOS
  • Capable of communicating with other featherweights to relay its location after it has landed
• SRAD Tracker
  • RS-41 Radiosonde Tracker
  • Powered by a 3.7V 5200mAh battery

Live Video Transmitter

• Walksnail Avatar VTX GT drone FPV system transmitting on 5.8GHz @ 2W
• Video will be received using FPV goggles
• The transmitter is included to allow us to compete in the Live Video Challenge
• Capable of 1080p30 fps
• Successfully tested with a minimum range of 0.5 miles
• Powered by a 14.4V 3500mah battery

Backplane

• ​An SRAD system with four separate modules that communicate over ethernet
  • Radio Module: Communicates with the ground station and transmits telemetry data
  • Sensor Module:  Records telemetry data during flight
  • ​Power Module: Distributes power to the other modules
  • Deployment Module: Acts as a flight computer capable of sending deployment signals
    • It will not be connected to any flight critical charges this year
    • ​A fuse will be implemented across the deployment channels to verify success

Ground Station

• Radio applications
  • Audio I/O for radio applications
  • ​2x SDR
• Receives live telemetry and GPS data from Backplane
• Powered by a 100 watt power bank with an estimated 8 hour runtime

Payload

Mission Bay

• Top Section
  • Servos for Flipping Mechanism
  • Contains raceways for wires running to the servos/pumps
  • Pumps for Inflating Module
  • Plumbing for Module located in upper secti
• Middle
  • Main volume for inflating module
• Bottom
  • Payvionics Section
  • Contains all control and recovery electronics

​Self Righting 

• Flipping Mechanism
  • Servo motors actuate flipping arms to orient payload with bay door up 
  • Servo motor: MKS HV6160
  • Torque (8.2V):  18.6 kg-cm / 258.3 oz-in
  • Speed: 0.133 s (8.2 V)
• Mission Bay Door
  • ​Flipping arms constraints mission bay door while in flight
  • Once payload is oriented upward, inflatable module will push open the door

Inflatable Module

• LLDPE Inner tube
• Tyvek outer shell
• ​Bazooka antenna tuned to 433MHz
• Module Plumbing​
  • Two 1.8L per minute air pumps connect to manifold
  • SLS-printed manifold connects I/O to PRV
  • Manifold output connects to module for filling

Sabot

• 3D Printed PETG
  • ​​2 Caps, 4 Leaves
  • 2 Pieces / Leaf
  • Kevlar Shock cord runs through pieces in a loop

Payvionics

• Main Structure
  • Provides the frame for the rest of the Pavionic
  • Holds batteries 
    • ​5000mAh 7.4v - CTRL FREAK
    • 3500mAh 3.6v - Featherweight
• Electronics Sled
  • Slides into the main structure
  • All electronics are mounted to the plate
  • Allows for easy access to all hardware
  • Bottom Side Components
    • CTRL FREAK
      • CTRL FREAK’s mission is to control the self righting mechanisms, control the pump for the inflatable module, and control the sending of GPS coordinates once landed on the ground
  • Top Side Components
    • Runcams and Runcam Boards (2x)
    • Featherweight GPS Tracker
    • GPS antenna for CTRL FREAK
    • Screw switches (2x)
    • XT30 Mounting (Keyed)​​​

Recovery

Main Parachute

• 8’ diameter
• Packed Length: ~7in long
• Packed volume: 139.5 in3
• Cd of 2.6
• Mass: 709 g

Drogue Streamer

• Size: 8.25”x 250’ 
• Lengthening to 250’ from 110’
• Cd of .05 (Based on previous flight data)
• Packed Length: ~1 foot
• Mass: 1573.6g

Shock Cord

• 3/8” Kevlar
• Load rating: 4600 lbf 
• Length: 115 ft
• Packed Length: ~5 in
• Mass: 759 g

 ​Foxhunt Beacons (MicroFox MF-50)

• Backup tracking signal for rocket recovery
• 2 meter HAM band
• Range tested to 2.5 miles
• Size: 2.75” x 1.15” x 0.71”
• Mass: 104 g 
• Mounts:
  
  • ​3D-printed to fit the shape of bulkheads
    
    • Top mount fits to Clover Bulkhead
      
    • Bottom mount fits to Booster Bulkhead
  • Material: PETG
    
  • ​Mass:
  • Top: 11 g
    
  • ​Bottom: 10 g
  • Beacons secured with two zip ties
    

Competition Data

Competition Outcome

• Won the Charles Hoult Award for Simulation & Modeling
• Were named "Best Deployable Payload" by SDL
• Had the first full points recovery since before COVID
• Tied for best tech report with Monash University
• Scored 11th in our category and 16th overall