and Autonomous IDentification NASA USLI Preliminary Design Review - PowerPoint PPT Presentation

PLAID: Precision Launch and Autonomous IDentification NASA USLI Preliminary Design Review Carnegie Mellon Rocket Command November 17, 2017

Launch Vehicle Design

Overall Design Wildman Extreme Darkstar November 17, 2017 3

Why the Darkstar? • Starting baseline for our new team • Includes all main compatible launch vehicle components • Quality components • Full fiberglass body, motor mount, and centering rings • Metal tipped nose cone • Engine adaptability • Fits wide range of motors • 54mm or 75mm • Cost • Donated by team mentor November 17, 2017 4

Main Dimensions & Materials Component Dimensions* Material 4” D x 52” L Lower Airframe Fiberglass (G-12) 4” D x 11” L Recovery Bay (coupler) Fiberglass (G-12) 4” D x 2” L Switch Band Fiberglass (G-12) 4” D x 24” L Upper Airframe Fiberglass (G-12) 4” D 5 -1(L/D) Nose cone Fiberglass (G-12) with Aluminum tip Motor Mount 75mm Fiberglass (G-12) 3/16” thick Fins Fiberglass (G-10) 4" D 94” L ( OpenRocket) Total Rocket *Actual dimensions vary slightly from these manufacturer specifications, e.g. the 4” diameter measurement is used for all components that fit with a 4” airframe. November 17, 2017 5

Material Justification Launch Vehicle Material Comparison Cost (per inch Material of 4” length of 4" Ultimate Tensile Water Effects Stiffness (msi) Diameter Body Tube diameter body Strength (ksi) tube) Highly Susceptible - Kraft Paper weakens and $0.50 - - (Apogee Components) swells as it absorbs water Blue Tube 2.0 Water-resistant, but (Always Ready $0.81 - - not waterproof Rocketry) G12 Fiberglass $1.95 Negligible 60-80 5-10 (Wildman Rocketry) Carbon Fiber $4.60 Negligible 240 20-30 (Wildman Rocketry) November 17, 2017 6

Material Justification (continued) Carbon Fiber Fiberglass + Extremely high strength to + Cost-effective weight ratio + Waterproof + Waterproof + High strength to weight ratio + Low thermal expansion - Slightly higher thermal - Brittle expansion - Expensive November 17, 2017 7

Stability Parameters

Stability Parameters Center of Center of Gravity, CG (in. Pressure, CP (in. Static Stability Mass (lb) from forward from forward Margin (cal) end) end) 12.25 58.20 76.67 4.55 Dry Wet 16.625 65.09 76.67 2.86 (with current chosen motor) November 17, 2017 9

Motor Selection

Selection Criteria 1. The motor must be reloadable. 2. It must be manufactured by Aerotech, CTI, or Loki 3. The output apogee altitude must be within a range of 5,400 to 7,000 ft. 4. The motor thrust curve must feature a neutral-regressive burn profile with a high initial thrust peak. 5. The required ballast to lower the apogee under ideal (no wind) conditions must be less than 10% of the total design weight (motor included). 6. Must provide a rail-exit velocity of 52 fps or above 7. Must be commercially available with multiple suppliers. November 17, 2017 11

Selected Motor November 17, 2017 12

FLIGHT PROFILE WITH BALLAST CORRECTION Rocket Flight Profile with CTI K650 in 10 MPH winds November 17, 2017

Launch Parameters

Thrust-to-Weight Ratio • Based on the CTI K650 Smokey Sam: • 657.68 N of average thrust • PLAID weight: • 74 N • Thrust-to-Weight Ratio • 8.91 • This is a sufficient thrust-to-weight ratio for Project PLAID November 17, 2017 15

Rail Exit Velocity • Minimum Required Velocity: 52 ft/s • Achieved Velocity: 78.9 ft/s • Based on engine thrust curve of CTI K650 • Based on OpenRocket flight simulation November 17, 2017 16

Subsystem Breakdown

Summary Approximate Subsystem Description Mass (lb) Length (in) Includes the lower body tube, motor Lower Airframe mount, centering rings, thrust plate, 11.3 52 retainer, fins, motor adapter and motor Includes the electronics bay, parachutes, Recovery 2.0 11 shock cords, and parachute protectors Upper Airframe Includes the upper body tube 1.8 24 Includes the nose cone, payload Payload electronics, camera, and camera 1.5 20 mounting system November 17, 2017 18

Lower Airframe Components • G12 body tube • G12 75mm motor mount • (2) G10 centering rings • (6) G10 beveled fins • Aluminum thrust plate and flanged motor retainer • Aluminum 54/75mm motor adapter • Motor with casing November 17, 2017 19

Lower Airframe: Fins • Split fins • Upper is tapered swept • Aspect Ratio = 0.929 • Lower is trapezoidal • Aspect Ratio = 1.192 Upper Fin • Pre-beveled • Considered tapering trailing edges • Fin flutter • 3/16" thickness Lower Fin November 17, 2017 20

Lower Airframe: Thrust Plate and Retainer • Aluminum vs. plastic retainer • Kaplow clips and Engine clips eliminated due to lack of strength • Aluminum retainer best practice • Material strength • Heat • Thrust plate recommended by mentor to distribute motor launch forces November 17, 2017 21

Lower Airframe: Thrust Plate and Retainer 75mm Motor Retainer 75mm Thrust Plate November 17, 2017 22

Lower Airframe: Motor Adapter • Allows flexibility with motor diameter • Mates with Aeropack Engine Retainer November 17, 2017 23

Recovery Components • Electronics Bay • G12 coupler • G12 switch band • (4) G10 bulk plates • 3D printed sled • (2) PerfectFlite Stratologger CF Altimeters • (2) Schurter rotary switches • Other electrical components (wires, JST connectors, battery) • Fasteners and hardware (screws, threaded rods, eye-bolts, black powder compartment, etc.) • Drogue SkyAngle Classic Parachute (24”) • Main SkyAngle Classic Parachute (60” • Considering larger for safety factor • (2) Nomex Parachute Protectors • (2) Kevlar shock cord • (2) Nylon schock cord protectors November 17, 2017 24

Recovery: Circuit Design • Two altimeters provide redundancy for both charges • Contains both drogue and main parachute charges • Altimeters each have dedicated power supply • Altimeters each have dedicated switch November 17, 2017 25

Recovery: Altimeter Selection PerfectFlite Stratologger CF Missile Works RRC2+ Missile Works RRC3 $58.80 $44.95 $79.95 Price 2"L 2.28"L 3.92"L Dimensions 0.85"W 0.925"W 0.925"W 0.5"H ~0.5"H 0.563"H Weight (oz) 0.38 0.35 0. 59 ± 0.1% Not given Not given Altitude Accuracy Operating Voltage 9V nominal (4V to 16V) 9V(3.5VDC-10VDC) 9V(3.5VDC-10VDC) November 17, 2017 26

Recovery: Altimeter Selection Altimeter Pros Cons • Audibly reports peak altitude & max flight velocity via beeps • Up to 100,000’ msl altitude • 2 output channels PerfectFlite • • Output: drogue/main Does not include dt4u data transfer Stratologger CF • Collects 20 samples/sec kit • Stores 16 flights • (18 min/each) of data • Programmed using a DIP switch configuration • Up to 100,000 msl altitude • Programmable High/low audible beep tone • Missile Works RRC2+ 2 output channels • Output: drogue/main • Easily mountable • 16 bit series mCU / altitude sensor has 24 bit ADV • Reports peak altitude & max flight velocity • Up to 100,000’ msl altitude • Programmable High/low audible beep tone • Heavier • Missile Works RRC3 Altimeter sensor has 24 bit adc • Longer • Stores 15 flights • (28 min/each) of data • 3 output channels: drogue/main/auxiliary November 17, 2017 27

Recovery: Altimeter Selection • PerfectFlite StratoLogger CF • Compact • Ample performance • Own already • Low cost for first year in competition November 17, 2017 28

Recovery: Sled Selection November 17, 2017 29

Recovery: Sled Selection Sled Type Pros Cons • • Cheap (<$5 for material) Time will be spent on • Easily machined/laser cut making a custom sled Plywood • Can create our own custom design or design • buy from online Weakest of all choices • Strong • G10/Other Fiberglass Difficult to machine • Readily available scraps in our inventory • Already designed for plug and play use • More secure housing of battery and • Additive Aerospace switch Most expensive (~$35) • Can buy universal sled in case of altimeter change • Free • Self-designed 3D Printed More time and work • Most customizable November 17, 2017 30

Recovery: Sled Selection • 98mm SMART Sled from Additive Aerospace + Plug and play + Saves time - More expensive - Cannot Customize • Still considering designing our own • Free 3D printing November 17, 2017 31

Recovery: Switch Selection Pros Cons • Switch secured with a small flat blade Schurter rotary screwdriver, to lock position of switch • switch Provides vent for pressure altimeters. • Affordable ($10) • More susceptible to external forces • Simple spring- Affordable ($6) disrupting the position of the switch • loaded switch Straightforward, functional • May be armed or disarmed by accident. • Push switch in ON position for a few seconds to connect power to altimeter which allows Push-Hold • switch not to change position easily. On the expensive side ($20) Switch Trigger • Insensitive to resistive or capacitive load • G-force tested at 300 Gs November 17, 2017 32