Critical Design Review University of Alabama in Huntsville - PowerPoint PPT Presentation

NASA SL Critical Design Review University of Alabama in Huntsville University of Alabama in Huntsville 1/16/2018 1 USLI CDR

LAUNCH VEHICLE University of Alabama in Huntsville 1/16/2018 2 USLI CDR

Vehicle Summary ry • Launch Vehicle Dimensions – Fairing Diameter: 6 in. – Body Tube Diameter: 4 in. – Mass at lift off: 43.8 lbm. – Length: 103 in. • Concept – L-Class Solid Commercial Motor – Rover Delivery – Electronic Dual Deployment – Fiberglass Airframe University of Alabama in Huntsville 1/16/2018 3 USLI CDR

Vehicle CONOPS Deploy Drogue: 19 seconds 5,429 ft. Powered Ascent: 0 – 3.3 seconds 0 – 1,190 ft. Deploy Main: 62 seconds 600 ft. Landing: 121 seconds 0 ft. Deploy Rover: Team Command University of Alabama in Huntsville 11/3/2017 4 USLI PDR

Vehicle Summary ry Tracking/Rover Deployment Recovery Avionics Avionics Rover Piston Fins (x4) Main Drogue Parachute Parachute CP CG 69 in. 56 in. Payload Fairing Forward Aft 36 in. Airframe Airframe Coupler 30 in. 42 in. 12 in. University of Alabama in Huntsville 1/16/2018 5 USLI CDR

Upper Air irframe Overview • Upper Airframe houses the rover, piston ejection system, and GPS tracker University of Alabama in Huntsville 1/16/2018 6 USLI CDR

Nose Cone • 6 in. elliptical shape; 6.17 in. OD; • ABS Plastic; 3-D printed in-house • 1.75 in. shoulder; shear pinned to fairing • 0.25 in. Aluminum bulkhead University of Alabama in Huntsville 1/16/2018 7 USLI CDR

Fairing • Houses payload and deployment device • Fiberglass; 6.17 in. OD, 6 in. ID • Shear pinned to nose cone; 10-32 bolt connection to transition University of Alabama in Huntsville 1/14/2018 8 USLI CDR

Transition • Three piece design, two 3D printed ABS plastic, one 0.5 in. thick aluminum bulkhead • Each piece has holes for threaded inserts • Held together using ¼-20 and 10-32 bolts Forward Insert Aft University of Alabama in Huntsville 1/16/2018 9 USLI CDR

Transition • Three piece design allows for a 57% reduction in weight • Max stress on aluminum bulkhead: 0.712 ksi • Yield stress: 42 ksi University of Alabama in Huntsville 1/16/2018 10 USLI CDR

Transition Coupler • Connects 4 in. body tube to the 6 in. fairing • U-bolt for recovery harness attachment point • Shear pins connect to 4 in. body tube • Threaded rod with hex nuts for connection to fairing University of Alabama in Huntsville 1/16/2018 11 USLI CDR

Piston Overview • CO 2 Powered – 12 gram cartridge • Spring driven spike used to release stored gas • 60 lbf. test monofilament fishing line used as arming tether for spring • Hot wire cuts tether to release spring • Two main components: piston head and CO 2 housing University of Alabama in Huntsville 1/16/2018 12 USLI CDR

Piston Head • Ejects rover and nose cone • Fiberglass coupler with aluminum bulkhead University of Alabama in Huntsville 1/16/2018 13 USLI CDR

CO CO 2 Housing • Houses CO 2 cartridge and release mechanism • 3D printed ABS Plastic • Allows for easy and quick modification upon testing results University of Alabama in Huntsville 1/16/2018 14 USLI CDR

Piston Configuration • CO 2 housing positioned in transition shoulder • Mounted to side using 3-D printed brackets and 4-40 bolts • Keeps housing fixed during flight University of Alabama in Huntsville 1/16/2018 15 USLI CDR

Aft ft Subsystem Overview • Aft Subsystem Components Fin(s) Fin Can Thrust Plate Recovery Bulkhead & U-Bolt Motor/Motor Case Motor Retention Ring University of Alabama in Huntsville 1/16/2018 16 USLI CDR

Fins • Trapezoidal Fin Set (4) – Maintain stability • G10 Fiberglass – Great strength/weight ratio – 3/16” thickness • Flutter Speed – Calculated to be Mach 1.947 (2191.57 ft./sec) University of Alabama in Huntsville 1/16/2018 17 USLI CDR

Fin In Interface • 4 bolts perpendicular to fin face • 6 bolts normal to body tube to hold shape – Also used to hold fin can in vehicle • Entire assembly can be removed University of Alabama in Huntsville 1/16/2018 18 USLI CDR

Fin in Can Assembly Overview • Consists of: Fin Can, Motor Retention Ring, Thrust Plate, and Rail Button Press fit nut University of Alabama in Huntsville 1/16/2018 19 USLI CDR

Exploded Vie iew of f the Fin in Can Assembly University of Alabama in Huntsville 1/16/2018 20 USLI CDR

Fin Can • 3D Printed in house • Material: ABS plastic • Purpose: Fin retention and centering of the motor • Attached to the body tube using 4-40 bolts which maintain the shape of the Body tube University of Alabama in Huntsville 1/16/2018 21 USLI CDR

Fin Can Dimensions University of Alabama in Huntsville 1/16/2018 22 USLI CDR

Thrust Plate • Machined in house • Material: 6061 Aluminum • Purpose: Transfer motor thrust to the airframe • Attached to the fin can using the motor retention bolts • Part was added due to concern of shearing the Fin Can while during motor burn University of Alabama in Huntsville 1/16/2018 23 USLI CDR

Thrust Pla late Dim imensions University of Alabama in Huntsville 1/16/2018 24 USLI CDR

Motor Retention Ring • 3D printed in house • Material: ABS plastic • Purpose: Motor retention • Attached to the fin can using the motor retention bolts • Aft retention was chosen due to the difficulty of disassembling the forward retention system University of Alabama in Huntsville 1/16/2018 25 USLI CDR

Motor Retention Rin ing Dim imensions University of Alabama in Huntsville 1/16/2018 26 USLI CDR

Motor Selection • Aerotech L1420R-PS Motor Altitude – Best met altitude target Aerotech L2200 6107 ft. • Avg. Thrust: 326.18 lbf. Aerotech L1420 5429 ft. Aerotech L1520 4329 ft. • Burn Time: 3.2 sec University of Alabama in Huntsville 1/16/2018 27 USLI CDR

OpenRocket Fli light Sim imulation • Dimensions – Total length – 103 in. – Wet mass – 43.80 lbm. – CP location – 68.93 in. – CG location – 55.60 in. 55.60 inches 68.93 inches University of Alabama in Huntsville 1/16/2018 28 USLI CDR

Stability Margin Motor Burnout (3.28 cal.) Apogee Initial Stability (2.22 cal.) University of Alabama in Huntsville 1/16/2018 29 USLI CDR

OpenRocket Fli light Sim imulation Attribute Value Apogee (ft.) 5429 Length (in.) 103 Max. Mach Number 0.60 Rail Exit Velocity (ft./s) 60.6 Static Stability (cal.) 2.22 AT L1420R – P Motor Designation Thrust-to-Weight Ratio 8.7 CG 56 in. CP 69 in. University of Alabama in Huntsville 11/3/2017 30 USLI PDR

OpenRocket Fli light Sim imulation Apogee (18.62 sec.) Motor Burnout (3.27 sec.) Main Deploy (62.39 sec.) University of Alabama in Huntsville 1/16/2018 31 USLI CDR

Full ll Scale Monte Carl rlo Sim imulation • 1-D method used to verify OpenRocket sim – Goal: Determine uncertainty in projected altitude – Randomly varies conditions by a percentage ▪ drag coeff., vehicle mass, propellant mass, case mass ▪ Varied between ± 6.25% and ± 2.5% – Use drag coefficient from subscale flight ▪ 𝐷 𝑒 = 0.56 – 10,000 flights per simulation University of Alabama in Huntsville 1/16/2018 32 USLI CDR

Full ll Scale Monte Carl rlo Sim imulation Mean: 5626.31 feet Median: 5617.45 feet Std. Deviation: 192.29 feet Max Altitude: 6463.91 feet Min. Altitude: 5010.83 feet University of Alabama in Huntsville 1/16/2018 33 USLI CDR

Central Subsystem Overview • Central Subsystem responsibilities: – Coupler between airframes – Flight Avionics – Ejection System – Tracking and Ground Station – Recovery System University of Alabama in Huntsville 1/16/2018 34 USLI CDR

Drift Analysis • Monte Carlo Drift Model – Assumes: V wind • Apogee is directly above the launch rail V relative • The parachute does not open immediately • The drift distance stops once a component lands • Horizontal acceleration is solely based on relative velocity • Drogue parachute is negligible once the main is fully deployed Wind Speed (mph) 0 5 10 15 20 OpenRocket Drift 17.6 465.8 946.7 1461.9 1995.7 Distance (ft) CRW Model Drift 0 573.19 1148.9 1741.9 2311.8 Distance (ft) University of Alabama in Huntsville 1/16/2018 35 USLI CDR

Recovery ry System Calc lculations • Requirement: No individual section will have a kinetic energy greater than 75 ft.-lbf. upon landing • Terminal velocity under drogue: 112.7 ft./sec. • Terminal velocity under main: 17.45 ft./sec. Vehicle Mass (lbm.) KE (ft.-lbf.) Section Fairing 14.35 67.85 Coupler 11.15 52.72 Aft 9.89 46.76 University of Alabama in Huntsville 1/16/2018 36 USLI CDR

Recovery ry System • • Drogue Parachute Deployment: Main Parachute Deployment: – Deployment at apogee – Deployment at 600 ft above ground – Fruity Chute CFC-18 (Cd = 1.5) level – Shock Cords: 1 inch Nylon (50 ft) – Fruity Chute 96” Iris Ultra (Cd = 2.2) – Connected between forward motor – Shock Cords: 1 inch Nylon (50 ft) – Connected between fairing retention bulkhead in lower airframe and avionics bay housing. bulkhead and avionics bay housing. – Descent speed under drogue: – Descent speed under main: 17.45 112.7 ft/s ft/s University of Alabama in Huntsville 1/16/2018 37 USLI CDR