Preliminary Design Review

University of Colorado BoulderNASA 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

Drogue Parachute

Electronics Bay

Motor Section

Liquid Sloshing

Main Parachute

HazCam & GPS

Aerodynamic Analysis

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– 1.1 The 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.– 1.5 The 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

– 1.6 The 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.– 1.7 The 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

– 1.8 The 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

Motor Section

Main Parachute

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 - Current State

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

AIM USB Altimeter

Sprinkler Valve

Pressure Sensor

Data Logger

• 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

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

Vinyl Tubing

Pressure/ Velocity Sensors

MCUSD Card

and COM 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 BoulderNASA Student Launch 2013-14