PLAID: Precision Launch and Autonomous IDentification NASA USLI Flight Readiness Review Carnegie Mellon Rocket Command March 9, 2018 1
Launch Vehicle Design January 24, 2018 2
Overall Design • Split fins • Carbon fiber camera shroud • Metal-tipped nose cone January 24, 2018 3
Main Dimensions & Materials Component As Built Dimensions Material Lower Airframe 4” D x 31.7” L Fiberglass (G-12) Avionics Bay (coupler) 4" D x 12" L Fiberglass (G-12) Avionics Bay (switch band) 4" D x 2.75" L Fiberglass (G-12) Middle Airframe 4" D x 16.4" Fiberglass (G-12) Recovery Bay (coupler) 4” D x 11.6” L Fiberglass (G-12) Recovery Bay (switch band) 4” D x 1.1” L Fiberglass (G-12) Upper Airframe 4” D x 21.9” L Fiberglass (G-12) Nose cone 4” D 5/1(L/D) Fiberglass (G-12) with Aluminum tip Motor Mount 75mm Fiberglass (G-12) Fins 3/16” thick Fiberglass (G-10) Total Rocket 4" D x 90.3” L January 24, 2018 4
Nose Cone • 4" 5-1 Von Karman • Polished to reduce surface drag • Optimized shape for operating velocity Nose Cone Drag Coefficient Drag Coefficient Drag Coefficient Shape at Mach 0.3 at Mach 0.5 at Mach 0.8 Cone 0.06 0.07 0.10 Von Karman 0.04 0.04 0.03 Parabolic 0.04 0.04 0.03 Ellipsoid 0.06 0.06 0.07 Tangent ogive 0.04 0.04 0.03 Power series 0.04 0.04 0.03 January 24, 2018 5
Fins • Upper Fin Aspect Ratio: 0.929 • Lower Fin Aspect Ratio: 1.23 • G10 Fiberglass Upper Fin CAD Model • Beveled • Maximum flutter boundary speed: 1452.14 mph Lower Fin CAD Model January 24, 2018 6
Motor Retention Method • 6061 Aluminum • Thrust Plate, 75mm flanged motor retainer, 54/75mm motor adapter • 18-8 Mounting Hardware Simulation Results Motor Retainer Base Thrust Plate Under Maximum Thrust from Motor Under Maximum thrust from Motor • • Maximum Displacement Maximum Displacement • • • 4.902e- 4 in • 1.173e- 4 Minimum Factor of Safety Minimum Factor of Safety • • • 2.8 • 31 January 24, 2018 7
Ballast Container • Fill with bag of lead shot • Fully adjustable • Match ballast curve • Place bag into container • Press fit with foam to prevent the bag from moving • Fixed to aft end of avionics bay • Below CG to prevent over stability and weathercocking January 24, 2018 8
Mass and Flight Stability January 24, 2018 9
Statement and Margin OpenRocket values Measured/Calculated CP 77.541 in 76.50 in CG (unballasted, 62.442 in 61.04 in wet) CG (unballasted, 56.35 in 54.54 in dry) Wet: 3.717 cal Wet: 3.806 cal Stability Margin Dry: 5.216 cal Dry: 5.406 cal January 24, 2018 10
Static Margin Diagrams January 24, 2018 11
Motor Description January 24, 2018 12
CTI K711 White Type Reloadable Propellant White Propellant; APCP motor Information Size 54 mm Motor Length 572 mm Burn Time 3.4 sec Total Impulse 2372.2 N-s Max Thrust 1700.6 N Total Mass 2198.0 g Propellant Mass 1398.0 g January 24, 2018 13
CTI K711 White January 24, 2018 14
Launch Parameters January 24, 2018 15
Thrust-to-Weight Ratio Motor Brand/ Designation CTI K711 Max thrust: 382.80 lbs Max/Average Thrust (lb.) Average thrust: 159.70 lbs Total Impulse (lbf-s) 534.43 Mass Before/After Burn (lb.) Before: 4.85 After: 1.62 Liftoff Thrust () 382.8 January 24, 2018 16
Rail Exit Velocity • Achieved: 74 ft/s • Minimum: 52 ft/s • Neutral regressive motor thrust curve • High initial thrust • High rail exit velocity January 24, 2018 17
Choosing the Appropriate Ballast January 24, 2018 18
Recovery January 24, 2018 19
Recovery Characteristics Drogue Main Type SkyAngle 24 inch Fruity Chute 84” Harness Material Kevlar Nylon Harness Length (ft) 17 25 Harness Thickness (in) 3/8 1/2 January 24, 2018 20
Parachutes • Drogue: • Skyangle 24" • 68.91 ft/s descent rate Skyangle Parachute FruityChute Iris Ultra • Main: 84" • FruityChute Iris Ultra 84" • 14.30 ft/s descent rate • 65.92 ft-Ibs of Kinetic Energies of components upon landing Component Nose cone Upper Airframe Lower Airframe Kinetic Energy (ft-Ibs) 6.48 14.93 34.24 January 24, 2018 21
Predicted Drift Rough Refined • Drift was calculated using Wind Speed Calculation Calculation (mph) a homemade program (ft) (ft) • Covers more variables 20 3013 1801 than standard methods 15 2260 1223 • Apogee values agree with OpenRocket 10 1507 686 • Produces drifts well within 5 753 289 maximum NASA requires 0 0 0 January 24, 2018 22
Predicted Apogee Wind Program Required Velocity predicted apogee • OpenRocket Ballast (Ibs) (mph) (ft) simulations predicted apogee altitudes 20 1.625 5280 • Ballast will likely be 15 1.95 5280 necessary to achieve 1 mile apogee 10 2.167 5280 5 2.3 5280 0 2.3 5280 January 24, 2018 23
Recovery Bay January 24, 2018 24
Recovery Bay Electrical Diagram •Two independent systems •Each have drogue and main charges •Secondary altimeter system has slight delay January 24, 2018 25
Full Scale Flight Test January 24, 2018 26
Launch Day Apogee Altitude (ft) 1966 Maximum Velocity (ft/s) 340 Wind Speed (mph) 16 Drift Distance (ft) 1,300 Humidity 75 Flight Time (s) 60 Temperature (°F) 50 Time to Apogee (s) 13 Launch Angle (degrees) 5 Nosecone: 9.67 Ballast mass (lbs.) 2.34 Landing Kinetic Energy (ft- Upper Airframe: 24.05 lbf) Lower Airframe: 65.26 January 24, 2018 27
Flight Data January 24, 2018 28
Encountered Issues January 24, 2018 29
Recovery System Tests • Ejection Charge Test • Drogue: 2.5g • Main: 0.5g • Both successful January 24, 2018 30
Payload January 24, 2018 31
Payload Design and Dimensions Parallel plate sled • Coupler in lower airframe • 9" tall • 3.125" wide • 19.3 oz (excluding coupler) • January 24, 2018 32
Payload Housing • G12 Fiberglass Coupler • Modified shroud route • Shroud screw holes • G10 Fiberglass Bulkhead • Eye bolt holes • Two threaded rod holes • Liquid Fyre Camera Shroud • Molded from 5 layers of twill carbon fiber January 24, 2018 33
Structural Components • Two 1/8" acrylic sleds • Two 3D printed sled links • Sleds slide into links and are bolted into place January 24, 2018 34
Electronics Integration Flight Computer serves as information • hub • SenseHAT connects via GPIO pins • Camera connects via soldered wires onto USB leads • Battery connects via soldered wires onto GPIO pins • Raspberry Pi distributes power from battery to all connected electronics January 24, 2018 35
Electrical Components January 24, 2018 36
Battery Change Zilu Battery Pack required micro-USB to • USB cables Internal hardware was unverifiable • Difficult to interface with • Purchased independent 18650 batteries • (same as Zilu battery) 5V regulator • All connections can be soldered • January 24, 2018 37
Electrical Connections • DE-9 D-Sub Connectors • Secure connections fastened by tightened screws • All wires can be soldered onto D- Sub • Exposed wire covered in heat tape or rubber tubing January 24, 2018 38
TDS Program Logic • Autonomous initiation of TDS • Analyze images based on expected HSV, size, and shape of targets • Interface with SenseHAT for acceleration data • Label and store all identified targets January 24, 2018 39
Launch Vehicle Interfaces • Payload coupler slides into lower airframe • Rigidly attached with button bolts and PEM broaching nuts • Connect camera lens to ribbon cable once payload is fixed • Middle airframe slides over payload coupler • Rigidly attached with button bolts and PEM broaching nuts • Shock chord is tied to eye bolt of upper bulk plate January 24, 2018 40
Ground Systems Interfaces 41
GPS • Mounted in nose cone with home base receiver • Coordinate readout on LCD screen January 24, 2018 42
TDS • Raspberry Pi connects to mobile hotspot • Can transfer files using PuTTY from laptop • Obtain target detection data from flight January 24, 2018 43
Requirements Verification January 24, 2018 44
Completed Requirements Verification Section Progress To Be Completed General 14/14 Educational Outreach Apogee, Preparation Time, Standby Time, Launch Vehicle 21/21 Full Scale Test Launch Ground Ejection Charges, GPS, Recovery 11/11 Electronics Shielding Payload 5/5 Target Detection Accuracy and Testing Safety 5/5 Full Scale Test Launch January 24, 2018 45
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