PLAID: Precision Launch and Autonomous IDentification NASA USLI - PowerPoint PPT Presentation

PLAID: Precision Launch and Autonomous IDentification NASA USLI Critical Design Review Carnegie Mellon Rocket Command January 24, 2018

Launch Vehicle Design

Overall Design January 24, 2018 3

Overall Design January 24, 2018 4

Main Dimensions & Materials Component Dimensions Material Lower Airframe 4” D x 32” 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" Fiberglass (G-12) Recovery Bay (coupler) 4” D x 11” L Fiberglass (G-12) Recovery Bay (switch band) 4” D x 2” L Fiberglass (G-12) Upper Airframe 4” D x 24” 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 98.2” L (OpenRocket) January 24, 2018 5

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 6

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 7

Motor Retention Method • 6160-T6 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 8

Mass and Flight Stability

Statement and Margin Center of Center of Estimated Static Gravity, CG Pressure, Mass (lb) Margin of Stability (in. from CP (in. from Error (lb) Margin (cal) forward end) forward end) Dry 19.38 ±2 55.849 77.541 5.34 Wet (with current 25.4 ±2.5 61.429 77.541 3.95 chosen motor) January 24, 2018 10

Static Margin Diagrams January 24, 2018 11

Motor Selection

Motor Selection Criteria 1. The motor must be reloadable. 2. It must be manufactured by Aerotech, CTI, or Loki. 3. The output apogee must be within a range of 5,500 to 7,000 ft. 4. The motor thrust curve must feature a neutral-regressive burn profile with a high initial thrust peak. 5. The ballast required to lower the apogee under ideal (no wind) conditions must not exceed 10% of the total design weight (motor included). 6. Must provide a rail-exit velocity of 52 fps or above. 7. Must be in-stock at more than two online suppliers. January 24, 2018

Final Motor Selection • Changed from CTI K650SS to CTI K711 • Total impulse: 2374 N-s (533.7 lbf-s) • Estimated ballast: 2.26 lbs (8.93% of wet weight) • Apogee: 6003 ft Criteria Met? • Off-rail velocity: 74.4 fps Reloadable Yes • Wet weight: 4.846 lbs Aerotech, CTI, or Loki Yes • Dry weight: 1.76 lbs Apogee within 5500-7000 ft Yes Neutral-regressive burn profile with high initial Yes thrust peak Ballast under 10% of wet weight Yes Rail-exit velocity 52 fps or above Yes In stock at more than two online suppliers Yes January 24, 2018 14

Launch Parameters

Thrust-to-Weight Ratio • Lift-off thrust: • 1702.77 N • PLAID Weight: • 112.54 N • Thrust-to-Weight Ratio • 15:1 • More than sufficient thrust. January 24, 2018 16

Rail Exit Velocity • Minimum Required Velocity • 52 ft/s • Achieved Velocity • 74.1 ft/s • Reduces weathercocking January 24, 2018 17

Recovery

Recovery Characteristics Parameter Drogue Main Type SkyAngle 20 inch Rocketman 12 foot Harness Material Nylon Nylon Harness Length (ft) 20 20 Harness Thickness (in) 1 1 Terminal Velocity (ft/s) 103 14.4 January 24, 2018 19

Kinetic Energy Drogue Kinetic Energy Landing Kinetic Energy Section (ft-lbs) (ft-lbs) Nose Cone 355.6 6.95 Upper Airframe 883.5 17.27 Lower Airframe 2396.9 46.85 Total 3636 71.07 • Landing Kinetic Energy is below 75 ft-lb threshold January 24, 2018 20

Chosen Parachutes SkyAngle 20" Drogue Parachute Rocketman 12' Parachute January 24, 2018 21

Predicted Drift Wind Speed (mph) Drift Speed (ft/sec) Drift Distance (ft) 20 29.33 2354 15 22 1766 10 14.67 1177 5 7.33 588 January 24, 2018 22

Recovery E-Bay Components Schurter 3D printed Coupler (OD=3.896") Rotary altimeter sled Double-plated Bulk Switch (2) plates (2) Threaded Rods (2) Eyebolts (2) Nuts (lock and jam) Black Powder PerfectFlite 9V Battery Canisters (4) Stratologger (2) Altimeters (2) January 24, 2018 23

Recovery System Summary January 24, 2018 24

Choosing a GPS and TX unit Data logging Power source Transmission Transmission capabilities range frequency Eggfinder GPS Not included, External 2S Up to 10,000 900 mHz tracking system but is capable LiPo with 250 feet license-free of accepting mAH capacity OpenLog data logger Beeline 100 Included with External 2S Over 40 miles Any frequency mW GPS onboard non- LiPo with 250 in 70 cm band system volatile mAH capacity in 125 Hz steps memory (radio license required) January 24, 2018 25

Final GPS and TX Unit • Eggfinder GPS Tracking System • 2S 300mA 7.4V LiPo Battery • Soldering required to assemble GPS • Equipment available at Makerspace January 24, 2018 26

GPS Housing and Location • 3D Printed ABS Housing • GPS and battery strapped into place on inner sled • Outer shell screwed into the inner sled • Tied to upper airframe shock cord using eye bolt January 24, 2018 27

Test Plans and Procedures

Summary of Tests Test Objective Payload Testing Validate the integrity of TDS Launch Vehicle Drop Test Determine whether all sections of PLAID can withstand landing forces PLAID Ejection Charge Determine whether the ejection charges calculated are enough to break Test the shear pins and deploy the parachutes Launch Prep Test Determine whether PLAID can be prepared for launch in under three hours Launch Pad Mock Test Determine whether PLAID’s batteries can keep the altimeters and avionics bay ready to launch for one hour Launch Pad Test To determine whether PLAID can remain in a launch ready configuration for one hour. DIET PLAID Ejection Determine whether the ejection charges calculated are enough to break Charge Test the shear pins and deploy the parachutes. G12 Materials Testing Determine the elastic modulus and compressive strength of G12 January 24, 2018 29

Example Payload Testing • Objective to determine the following: • Can the TDS detect the targets • Amount of time required • Frequency of errors • Methodology • Supply video with different orientations of targets • Supply previous rocketry footage • Supply video from full scale rocket flight • Success Criteria • Detecting targets before apogee with 95% accuracy January 24, 2018 30

Example: Ejection Charge Test • Success Criteria • The shear pins are broken and the sections come apart. • Methodology • Find clear surface in a large outdoor field • One ejection charge loaded • Launch vehicle is positioned slightly above horizontal • Manually trigger charge with voltage • Examine shear pins to confirm break • Ensure separation of sections • Adjust ejection charge until successful • Successful pass on DIET PLAID Launch Day • Small failure of ejection charge during second launch • Adding buffer January 24, 2018 31

Example: G12 Fiberglass Materials Testing • Instron 4469 universal testing machine • Sample from Wildman Rocketry • Tensile testing necessary Material Characteristic Value Elastic Modulus 905700 psi Compressive Strength 46000 psi January 24, 2018 32

Scale Model (DIET PLAID) Flight Test

DIET PLAID Launch Day January 24, 2018 34

DIET PLAID Launch Day • Conditions • Minimum Temperature: 23°F • Maximum Temperature: 45°F • Humidity: 59% • Wind Speed: 3 mph Time to Apogee Flight Time Actual Apogee Launch Motor Apogee (ft) (sec) (sec) (ft) Aerotech 1 9.66 43.6 1354 1322 H115DM 2 CTI H170 11 43.1 1915 1670 3 CTI H410 8.99 43.2 1331 1307 January 24, 2018 35

DIET PLAID Flight Data Successful Unsuccessful January 24, 2018 36

DIET PLAID Influence on PLAID • Unsuccessful Trial • Main Parachute did not deploy • Too Little Black Powder • Almost Broke Shear Pins • For Full Scale • Make Calculations for needed black powder for a certain force on the chamber • Add 80 lbs to add a factor of safety January 24, 2018 37

Estimated Drag Coefficient • Dynamic similarity not established • Drag Coefficient of full scale determined by OpenRocket simulation of full scale • Estimated Drag Coefficient: 0.41321 January 24, 2018 38

Final Payload Design Overview