Team A.E.M.B.L. Critical Design Review

Transcription

1 Critical Design Review Members: Nick Bradley, Matt Lenda, Emil Reinovsky, Spencer Sator (Student Leader), Kevin Weber GPS System Designer and Team Leader: Stephan Esterhuizen 23 March 2006 Image from

2 Mission Overview Objective - Primary objective BalloonSat box will carry Mr. Esterhuizen s advanced GPS unit; designed to observe and record GPS signal reflections in relation to remote sensing - GPS unit will record information regarding wind currents (our original science goal) - HOBO data logger will collect temperature variation data - Will discover critical elements for implementing concept of GPS reflections and bistatics in practical applications at high altitudes (~30 km) - Remote sensing, military intelligence, passive communication and navigation

3 BalloonSat Design (Subsystems and Overall Requirements) Camera/timer system - Removed second camera for weight/space considerations - 12V batteries and switch Heating system - 9V batteries and switch HOBO data logger - External and internal temperature sensors - Own batteries for power CPU subsystem - Independent of other subsystems - Own power, memory storage - Additional heater not required; battery will provide additional heat for other subsystems Overall system requirements minor changes from Rev A - 3 hours of CPU operation provided by CPU battery - USB flash drives instead of hard disk - Less box volume to heat

4 BalloonSat Design (cont d) Tentative Completed BalloonSat Structure with Internal Components

5 BalloonSat Design (cont d) Functional Block Diagram of Internal Components 12V Batteries Switch 9V Batteries Switch Data Stream Computer Framing Design Timer Heater Switch Camera 1 Camera 2 Power for computer USB Hub HOBO Flash Memory Temperature sensor Internal Temperature sensor External

6 BalloonSat Design (cont d) Tentative Completed BalloonSat with Internal Components *Units in cm.

7 Management Schedule Schedule April 2: Team meeting Evaluate system performance, make plans to alter design or change construction, if necessary April 2-8: Make any necessary systems modifications agreed upon during previous meeting, complete Whip Test April 9: Team meeting Confirm launch schedule, make checklist for any remaining flight preparations, evaluate any additional modifications that may be necessary April 10-21: Any additional modifications or flight plans can be made during this time April 22: Launch date April 30: Organizational meeting for final report Image from:

8 Test Plan Drop Test (completed) - Kick test down 20 staircase - Minor damage to box, no impact to unit operation - Vertical drop test from 10 balcony - Wire detached from battery pack and relay circuit - All unit weaknesses addressed; system design strength confirmed - Designed to simulate ground impact Cold Test (23 March) - Expose box to cold of dry ice in a cooler - Test internal and external temperatures over a 3-hour period - Designed to simulate extended internal operation at high altitudes Whip Test (week of 3 April) - Whip the box to test structural integrity of components, to ensure survival from fall during flight - Designed to simulate balloon burst phase with torque and G-force

9 Mass Summary Complete list of components provided by HOBO 9V Batteries 12V Batteries Timing Circuit Heater Camera Insulation Box (foamcore( foamcore, aluminum tape) Switches and wiring Thermometer Sub-Total 30g 30g 30g 30g 50g 200g 100g 70g 50g 50g 640g

10 Mass Summary (cont d) Complete list of components provided by Mr. Esterhuizen SBC + Heatsink + USB Stick + Power (DC) Battery (provides power for ~3.5 hours) Cables Enclosure Sub-Total 500g (measure) 457g (measured) 50g (estimated) 250g (estimated) 1257g Final BalloonSat Mass Total: 1897g

11 Budget Summary Complete list of components provided by HOBO 9V Batteries 12V Batteries Timing Circuit Heater Camera Insulation Box (foamcore( foamcore, aluminum tape) Switches and wiring Thermometer Dry Ice Total $40 (estimated) $10 (estimated) $50 (estimated)

12 Expected Results USB drives will provide highly reliable data storage Blocks of data will be recovered from USB drives turning on at certain times GPS data logged and recorded with reasonable accuracy Expect detailed picture of wind velocity, relative humidity, and temperature as a function of elevation through several points in the atmosphere HOBO temperature data should match that of other groups; ascent and descent rates will be easily obtained with info on times of launch, balloon burst, and approximate altitude reached Ascent Rate = (max altitude) / (time from launch to burst) Descent Rate = (max altitude) / (time from burst to landing) Structure will prove to be reliable and will protect interior hardware from environmental and stress impairment

13