University at Buffalo GLADOS

SHOT II Balloon Payload Presentation

June 29, 2012

Andrew Dianetti, Alex Wende, Bryant Carlson, Joe Flannery

1

Mission Overview

• Test spectrometer data compression algorithm• Transmit compressed data to ground• Test ability to transmit and receive compressed

spectrometer data• Log data on payload and compare received data to actual

transmitted data• Test in sample satellite conops routine with health

beacon

SHOT II/UN-7 Connection

• GLADOS Mission Statement: Utilize multi-band photometric data of glinting space objects to identify their type, surface materials, and orientation.

• Spectrometer measures photometric data• Data must be compressed to downlink• Successful reception of spectrometer data critical to

mission objectives

SHOT II Design - Hardware

BOM:• Payload housing – 3/16” foam core with ¾”

polystyrene• Flight line attachment – ¼” ID PFTE tubing• “Flight computer” – Arduino Mega• Spectrometer Data Processor – PandaBoard• Radio – Friendcom FC-401/D with

OpenTracker• GPS – Byonics GPS4• Heaters – (5) 3.9 ohm 5W resistors• Temperature sensors• (2) Mini Video Cameras

Arduino MegaGPS

Temp sensorRadio

Panda Board

Heater control MOSFET Heater

Battery

Voltage Regulator

Spectrometer Data (SD)

Flash memory

Heater Battery

Inhibit

Inhibit

TNC

Antenna

Cameras

SHOT II Design – SoftwareRelease inhibit

Start Health Beacon

Temperature regulation

Wait for PandaBoard boot Load program

“Take” spectrometer data (from SD card)

Compress data

Output compressed dataListen for data

Transmit data to ground

Log data to flash

RS-232 Link

RS-232 Link

Ascending?

Query more data

Query data?

RS-232 LinkY

Command shutdown

N

Wait for signal

Y

Shut DownN

Health OK?

Y

N

Transmit health data

SHOT II Design: Compliance

• Weight: 1393 g (<1500 g)• Flight string attachment: ¼” PFTE w./ shear pin• RF: 145.600 MHz Half-Duplex, EIRP 0.32 W• Labeled with contact info, flag

SHOT II Test Details

• Functional Test– 3 hours run time– Battery close to full charge at

conclusion (10.9 V)– Successful radio link, but limited

range (~2 mi)• Expect increase with better line-

of-sight• Thermal test

– Initial test drained battery in ~2 hr– Added separate battery pack for

heaters– 3 hrs with Temp above 1°C

SHOT II Test Details

• Whip Test– No issues of note

• Drop Test (~18 feet)– Slight damage to corner of

test article, no impact to internal mass objects

• Stair Pitch Test (15 concrete steps)– Slight scratches and

scrapes, no impact to internal objects

Expected Results

• Expect health data for entire flight• Flight computer to command PandaBoard based on

GPS• Transmitted data to be logged to SD card• Expect data error to increase with distance

– How does varying loss rates during downlink affect packets recovered?

• Flight conditions are better model than ground test

Demonstrations

• Payload shown• Demonstrate activation of payload