Download QuakeSat Lessons Learned: Notes from the

Table of Contents
1
Early Planning and Requirements............................................................................................ 4
1.1
Decision to Build a Satellite .............................................................................................. 4
1.2
Assessing Cost .................................................................................................................... 4
1.3
Requirements ...................................................................................................................... 4
2
Satellite ......................................................................................................................................... 5
2.1
Communications ................................................................................................................ 6
2.1.1
Onboard Modem ....................................................................................................... 6
2.1.2
Link Utilization.......................................................................................................... 7
2.1.3
Communication Software ........................................................................................ 7
2.2
Attitude Determination and Control............................................................................... 8
2.2.1
Magnetic Stabilization .............................................................................................. 8
2.2.2
Attitude Prediction/Determination........................................................................ 8
2.3
Computer and A/D Converter ........................................................................................ 9
2.3.1
Choosing Hardware and Software ......................................................................... 9
2.3.2
Satellite Software ..................................................................................................... 11
2.3.3
Time........................................................................................................................... 13
2.3.4
Data Collection and Digitizing .............................................................................. 14
2.3.5
File-based Download .............................................................................................. 14
2.4
Mechanical Design and Construction ........................................................................... 14
2.4.1
Cleanliness and Contamination Requirements................................................... 14
2.4.2
Heat Dissipation ...................................................................................................... 15
2.4.3
Solar Arrays (Mechanical Design)......................................................................... 15
2.4.4
Machine Shop........................................................................................................... 16
2.4.5
Electrical Drawing Systems.................................................................................... 16
2.4.6
Mechanical Computer-Aided Design (CAD) ...................................................... 16
2.5
Power System ................................................................................................................... 20
2.5.1
Design Margin ......................................................................................................... 20
2.5.2
Telemetry Sensors for the Power System............................................................. 20
2.5.3
Solar Panels .............................................................................................................. 20
2.5.4
Batteries..................................................................................................................... 20
2.5.5
Charge Controllers .................................................................................................. 21
2.5.6
Power Supplies ........................................................................................................ 21
2.6
Payload .............................................................................................................................. 21
2.6.1
Payload and Downlink Interference..................................................................... 21
2.7
Other Sensors.................................................................................................................... 22
2.7.1
Telemetry Multiplexers .......................................................................................... 22
2.8
Reset Mechanisms............................................................................................................ 22
3
Ground Station........................................................................................................................... 23
3.1
Early Ground Station Activation ................................................................................... 23
3.2
Ground Station Software................................................................................................. 23
3.2.1
Architecture.............................................................................................................. 24
3.2.2
Verifying Antenna Pointing................................................................................... 24
3.2.3
Second Ground Station........................................................................................... 24
3.2.4
Maintenance ............................................................................................................. 26
3.3
Ground Station Telemetry .............................................................................................. 26
3.4
Ground Station Testing ................................................................................................... 26
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