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Preliminary Design Review. University of Colorado Boulder NASA Student Launch 2013-14. Overview. Launch Vehicle & Subsystems Recovery System Communications Systems HazCam Hazard Detection Liquid Sloshing Experiment Aerodynamic Analysis Payload. Vehicle Summary.
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Preliminary Design Review University of Colorado Boulder NASA Student Launch 2013-14
Overview • Launch Vehicle & Subsystems • Recovery System • Communications Systems • HazCam Hazard Detection • Liquid Sloshing Experiment • Aerodynamic Analysis Payload
Vehicle Summary • 168 inches long, 3.9 inch inside diameter • Carbon fiber body • High strength-to-weight ratio • Fiberglass nosecone • RF transparent
Vehicle Sections Aerodynamic Analysis Drogue Parachute Electronics Bay Main Parachute Motor Section HazCam& GPS Liquid Sloshing
Stability • Static stability margin
Stability (cont.) • Stability: 15 calibers • Center of Gravity location: • 69 inches from tip of the nose • Center of Pressure location: • 130 inches from tip of the nose Center of Gravity Center of Pressure
Vehicle Safety Verification Plan • Summary of Verification Plan • Structural Testing • Subscale Flights • Dual Deployment & Ejection Testing • Full Scale Flights
Motor • Cesaroni L-1720 White Thunder • Total impulse: 823 lbf-s • Average thrust: 398 lbf • Max thrust: 437 lbf • Burn time: 2.1 s
Motor Justification • Target altitude: 4,000 feet • Preliminary simulations predict 4,595 feet • Actual altitude will be lower due to mass increasing as design matures, added ballasts • Subsonic speeds (for aerodynamic analysis) • Maximum Mach number: 0.5 • Adequate payload experiment time during descent
Performance Summary • T:W ratio = 10 • Rail exit velocity = 103 ft/s • Max velocity = 562 ft/s • Max acceleration = 296 ft/s2
Launch Vehicle Verification Plan • Summary of Verification Plan • 1.1The vehicle shall deliver the research payload to an altitude of 4,000 above ground level • Satisfied by motor, ballasts; verified by analysis, test • 1.2 The vehicle shall carry one commercially available barometric altimeter for recording the official altitude for competition • Satisfied by altimeter; verified by analysis, test • 1.3 The launch vehicle shall be designed to be recoverable and reusable • Satisfied by recovery system, verified by analysis • 1.4 The launch vehicle shall be capable of being prepared for flight at the launch site within 2 hours, from the time the FAA waiver opens • Satisfied by demonstrated team ability, verified by test
Launch Vehicle Verification Plan cont. • Summary of Verification Plan cont. • 1.5The launch vehicle shall be capable of remaining in launch-ready configuration at the pad for a minimum of one hour without losing functionality of critical components. • Satisfied by battery-operated electronics; verified by test • 1.6The launch vehicle shall be capable of being launched by a standard firing system. The firing system will be provided by the NASA-designated Range Services Provider. • Satisfied by motor; verified by inspection
Launch Vehicle Verification Plan cont. • Summary of Verification Plan cont. • 1.7The launch vehicle shall require no external circuitry or special ground support equipment to initiate launch (other than what is provided by Range Services). • Satisfied by motor; verified by inspection • 1.8The launch vehicle shall use a commercially available solid motor propulsion system using ammonium perchlorate composite propellant (APCP) which is approved and certified by the NAR • Satisfied by motor; verified by inspection
Recovery System - Overview • Parachute Design • Elliptical Cupped • 15 ft. main parachute • 6 ft. drogue parachute • Parachute Material • 1.9 oz. rip-stop nylon • 1 in. woven nylon cord Elliptical Cupped Parachute —Source: http://www.the-rocketman.com/chutes.html Subscale Parachute
Recovery System - Parachute Placement/Deployment • Two elliptical cupped parachutes with dual deployment • Drogue Parachute • Apogee (target altitude: 4,000 feet AGL) • Main Parachute • 1,000 feet AGL Drogue Parachute Electronics Bay Main Parachute Motor Section
Recovery System - Hardware • Recovery Attachments • Long sections of shock cord attached by quick links to bulkhead coupler tube assemblies • Bulkheads made from wood with U-bolts attached • Shock cords attached to U-bolts Previous Electronics Bay
Recovery System- Avionics • Raven Featherweight altimeters • 1st event (drogue deployment) at apogee • 2nd event (main deployment) at 1,000 feet AGL • Redundant altimeter is Raven Featherweight Wiring for Raven3 Featherweight
Communication Systems - Overview • Wireless downlink to ground station • HazCam data • GPS data • Located in RF transparent fiberglass nosecone
Hazard Camera (HazCam) Payload - Overview • Scans ground looking for Hazards • Image is taken and sent to Raspberry Pi • Raspberry Pi analyzes image and looks for Hazard • When hazard is found, it is transmitted to ground station • All footage is saved onboard for post-launch analysis Drawing of Nosecone-HazCam Assembly
HazCam Payload - Block Diagram • HazCam connects to Comm System via USB to Arduino Board • Uses cost effective and easy-to-use Raspberry Pi hardware
HazCam Payload - Design • Used to process image • Handles transmission to Xbee transmitter • Built by makers of Raspberry Pi, comes with fully built library • Capable of HD video
HazCam Algorithm - Future Work • Increase Speed • Translate to C • Reduce False Positives
Liquid Sloshing Experiment - Overview • Innovative method of microgravity liquid fuel transport • Liquid fuel starts in pressurized tank • AIM USB altimeter opens solenoid valve at motor burn-out • Fuel forced from pressurized tank through valve to unpressurized tank • Valve closes at apogee (drogue deployment, end of microgravity phase)
Liquid Sloshing Experiment - Design • Solenoid switch activated by electrical pulse from altimeter • Compatible with PVC tubing • Programmable to send signal at peak velocity (burn-out) and apogee • High flight heritage and cost-effective Sprinkler Valve AIM USB Altimeter
Liquid Sloshing Experiment -Additional Design Considerations • PVC selected for sturdiness, availability, ability to be pressurized safely • Pressurized tank includes depressurizing ball valve for safety First Prototype of Liquid Sloshing Apparatus
Liquid Sloshing Experiment - Block Diagram • Pressure Sensor and Data Logger activated prior to launch, record data during entire flight • Altimeter activates Sprinkler Valve at motor burnout, deactivates at apogee • On-board systems do not interface with ground station in real time to save cost and space AIM USB Altimeter Pressure Sensor Sprinkler Valve Data Logger
Liquid Sloshing Experiment - Interface and Testing Plan • Interface With Rocket • Located in upper payload bay below nosecone • Payload supported and connected to rocket body by wooden bulkheads • Electronics sled in payload bay contains altimeter, data logger • Testing • Pressure testing for PVC to ensure 4:1 pressurization safety factor • Drop test to ensure payload survival in case of parachute failure • Operational testing on ground and during subscale launches • Electronics test pre-launch to ensure functionality
Aerodynamic Analysis Payload - Overview • The payload will measure aerodynamic flow over the side of the rocket • Will compare pressures over protuberances in two different types of flow • Compared against CFD results
Aerodynamic Analysis Payload Design - Structure • Protuberances with pressure ports constructed at and around payload • Pressure ports drilled at • Vortex generators ahead of one protuberance
Aerodynamic Analysis Payload Design – Pressure Measurement System • Pressure ports will be connected by vinyl tubing to pressure sensors • Four pressure ports per protuberance • (Increased/decreased as budget allows) • Microcontroller will read digital pressure sensor and velocity data • Store data to SD card • Downlink payload status to COM unit
Aerodynamic Analysis Payload Design – Test and Verification Plan • CFD will provide preliminary estimates of the effects of the protuberances on the flow • A subscale of the upper body tube will be constructed and tested in the wind tunnel on campus
Aerodynamic Analysis Payload - Data Analysis • Six sets of pressure data will be generated • Turbulent flow over protuberance • Laminar flow over protuberance • Control flow (no protuberance) • Pressure data from CFD simulations for each of the conditions listed above • This data will be compared numerically as well as qualitatively to see how the different flows compare • This will give insight as to how the protuberances affected the flight of the rocket and flow patterns around the rocket.
Questions? University of Colorado Boulder NASA Student Launch 2013-14