University of Colorado Boulder

NASA Student Launch 2013-14

Critical Design Review

Table of Contents

● Vehicle Design● Subscale Results● Recovery System Design● Hazard Camera● Liquid Sloshing● Aerodynamic Analysis● Schedule● Budget● Questions

Vehicle Design Overview

Vehicle Design Overview

•Vehicle Name: HYDRA (HYdrodynamics, hazard Detection, Research for Aerodynamics)

• Carbon Fiber Airframe– High stiffness to weight ratio

•Total Length: 154in•Diameter: 3.9”•Wet Mass: 32.1 lb•Static Stability Margin: 6.4•Target Altitude: 6,000 ft

Final Motor Selection

• Final Motor Selection: Cessaroni L1720-WT– Max/Avg .Thrust: 473/398 lbf– T/W Ratio: 12.4– Rail size: 12 ft 1515 rail– Rail Exit Velocity: 93.1 ft/s

Stability Margin

• Static Stability Margin: ~6-8

Mass StatementComponent Mass (lbs)Nosecone 2.750Hazard Camera Payload 0.124GPS and Radio Transmitter 0.222Aerodynamic Analysis Payload Total 3.960Upper Body Tube 1.920Drogue Parachute 0.292Liquid Sloshing Payload and Electronics 5.000Avionics Bay and Electronics 2.050Lower Body Tube 1.360Main Parachute 1.200Complete Motor Assembly and Fin Can 5.820Motor Casing 3.496Propellant 3.869

Total 32.063

Mass Statement

• Current Wet Mass: 32.1 lb•Potential mass growth: ~2.5 lb•Expected Weight: 33 lb•Mass Margin: +/- 2.5lb

–This will keep the team near their target altitude of 6000ft.

Subscale Results

Subscale Results

•Total Length: 99.5 in•Diameter: 54 mm•Wet Mass: 9 lb•Static Stability Margin: 6.4•Motor: Cesaroni K-360•Projected Altitude: 9216 ft

Subscale Results

• Static Stability Margin: ~6-10

Subscale Results

Recovery System

Parachute Design• Elliptical cupped

– Simple design• 8 ft. diameter main parachute

– Descent Rate: 18 ft/s• 3 ft. diameter drogue parachute

– Descent Rate: 50 ft/s

Example of elliptical cupped parachute

Manufacturing• Pattern cut from 1.9 ounce rip stop nylon• Sewed with rolled hem seam and Dual Duty XP Heavy Nylon

Thread• Reinforced with 1” tubular nylon which continue to become

shroud lines.

Chute Testing• Chutes will be dropped off

tall building with a small mass attached to determine drag coefficient.

• Strength test of seams will be done using a strength tester.

Parachute Placement/Deployment

• Main will deploy between first section and electronics bay

• Drogue will deploy between middle section and motor section– Trigged by two black powder charges each

deployment

First section

Electronics Bay

Middle section

Motor section

Kinetic Energy (ft-lbf)

Flight Events Motor Section Middle Section First Section

Motor Burnout N/A N/A 261,683

Main Deployment

56.75 770.86 377.5

Landing 52.24 70.97 34.75

Recovery attachments

• Two 25ft sections of 1” tubular Kevlar shock cord and one 1ft– One for each chute and one for payload

integration• Chutes attached by high strength (2,500 lbf)

swivel and 3/8” quick link to shock cord• Shock cord attached to bulkhead assemblies

using quick links.• Bulkheads are made of ¼” birch aircraft

plywood.

Avionics• Using Raven Featherweight altimeters• 1st event (drogue deployment) at apogee• 2nd event (main deployment) at 1,000 ft. AGL• Redundant altimeter is also a Raven

Wiring for Raven3 Featherweight

Vehicle Drift (0 mph)

Vehicle Drift (5 mph)

Vehicle Drift (10 mph)

Vehicle Drift (15 mph)

Vehicle Drift (20 mph)

Hazard Camera Payload

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/GPS-Comm System Integration

• Placed within nosecone

• Mounted on Fiberglass Sled

• Secured in place with 8-32 all-thread

• Hazard Camera is at top of nosecone

• Clear acrylic lid on top of nosecone

HazCam Algorithm - Current State

HazCam Algorithm - Future Work

•Increase Speed•Translate to C•Reduce False Positives

Liquid Sloshing Payload

Liquid Sloshing Overview

•Tests a new method for mitigating liquid sloshing in fuel tank in microgravity

•Fuel contained in flexible bag in pressurized container•Acceleration data and camera videos recorded by Raspberry Pi on SD card•Data processed post-flight

Experiment Design and Analysis

•Control tank: water free to move about tank

•Experimental tank: water confined to flexible bag in pressurized tank

•Tanks isolated by electronics bay•Acceleration data measured•Data verified by video data•Two launches: full scale and competition for greater sample size and less error

Liquid Sloshing Design

• Overall Dimensions: 17” long, 3.9” diameter• Placed in middle body tube of rocket just above drogue

parachute• Bulkheads bolted into rocket body hold payload in place• Two tanks: control and experiment, separated by electronics

bay• Accelerometer mounted to outside of experimental tanks• LEDs light up coupler tubes for camera

Electronics Overview

• Data from camera and accelerometer processed by Raspberry Pi microcomputer

• Data stored on SD card for post-flight analysis• Raspberry Pi powered by 5V USB charger, camera

and accelerometer powered through Pi• LEDs powered by 2x 9V batteries in electronics bay

Liquid Sloshing Integration

•Payload built utilizing coupler tubes and bulkheads that are similar to avionics bay

•Payload is bolted into rocket body tube through ½” bulkheads

Testing Plan

•Pressure test acrylic tank to ensure 4:1 pressurization safety factor

•Drop test to ensure payload survival in case of parachute failure

•Accelerometer test to confirm it can withstand 13g liftoff accelerations

•Systems integration testing to ensure proper component interfacing and wiring logic

Aerodynamic Analysis Payload

Aerodynamic Analysis Overview

Payload to satisfy requirement 3.2.2.2 – Aerodynamic analysis of protuberances during flight

Goals:•To determine drag of different shaped protuberances through pressure measurement

•To correlate and verify experimental data with CFD results

Aerodynamic Analysis Design•Three mock “SRBs” are attached to the rear of the rocket

•Each SRB has a different geometry•Pressure distribution over each SRB is measured

Scientific Overview•By measuring the pressure distribution over each protuberance, a drag force can be obtained

•Knowing the drag force as a function of the velocity of the rocket will allow for calculations

•The velocity of the rocket can be used as an input for CFD analysis to compare predicted and experimental results

Electronics•Isolation of systems•Managed data flow

•Hardware filters of analog signals

PressureVelocity Multiplexer Microcontroller SD Card

Aerodynamic Analysis Integration

•Mounted to rocket utilizing a rail system

•Each SRB is an independent apparatus

•Easy to assemble and dissasemble

Aerodynamic Analysis Testing •Structural testing•Static pressure testing

–Data recording–Circuit design–Sensor communication

•Dynamic pressure testing–Filtering–Noise levels–Leaks in pressure measurement system

Requirements Verification

Structures and Aerodynamics# Requirement Satisfying Design

FeatureVerified by: Status

SA.1 The airframe of the vehicle must be able to survive under all expected loads experienced

during flight.

Body Tubes and Couplers

Analysis, Test

Verified

SA.1.1 The airframe must survive a max longitudinal load of 400 lbf

Body Tubes and Couplers

Analysis, Test

Verified

SA.2 The airframe must be able to integrate with all on board payloads, electronics, and

recovery systems.

Avionics Bay, Body Tubes

Inspection Verified

SA.3 The airframe must integrate with the motor retention system.

Motor Tube, Motor Retainer

Inspection Verified

Propulsion and Guidance# Requirement Satisfying Design

FeatureVerified

by:Status

PG.1 The motor must stay within the vehicle at all times during

flight

Motor Retainer Analysis, test

Verified

PG.2 The motor must supply enough thrust for the vehicle to obtain the target altitude

of 6,000 feet

Motor Analysis, test

Verified

Avionics and Recovery# Requirement Satisfying Design

FeatureVerified

by:Status

AR.1 The recovery avionics must have a completely

independent backup system

Raven Featherweight Altimeters

Inspection Verified

AR.2 The recovery avionics must fit within the allotted space

in the avionics bay

Avionics Bay Inspection Verified

AR.3 The recovery system shall fit within the available tube

space.

Recovery System, Body Tubes

Inspection

Pending

AR.4 The recovery system shall be able to be deployed while

the rocket is in its flight configuration

Recovery System Test Pending

Ground Ops# Requirement Satisfying Design

FeatureVerified

by:Status

GO.1 The wireless transmitters must be able to downlink

all necessary data from the rocket in real time while in

flight configuration.

Transmitter, ground computer

Test Verified

GO.2 The range of the transmitter shall be more

than two miles when installed in its flight

configuration

Transmitter Test Verified

GO.3 The ground station must be able to store all

downlinked data in real time.

Ground computer Test

Verified

Project Plan

Schedule

BudgetCategory Cost

Vehicle & Payloads $3016.84

Outreach $100.00

Testing $100.00

Travel $3027.81

Misc. $100.00

TOTAL $6344.65

Educational Outreach Status

• Completed 1 Event – Reached over 90 middle-school students

• 2 more activities scheduled this month• 1 scheduled in April• On target to reach goal of working with 200 students

Questions?