attitude determination & control system group 930 & 931
TRANSCRIPT
Attitude Determination & Control System
Group 930 & 931
Requirements
• Inertial pointing satellite.
• Pointing Accuracy (10 deg off axis).
• Slew (25 deg off axis).
• Minimize power consumption
Control Modes
• Detumbling.
• Fail Safe.
• Power Save.
• Camera Control.
• (Communication Control).
Sensors
• Magnetometer.• Horizon Sensor.• Rate Gyros.• Sun Sensors.
Sensor combinations
1. Magnetometer & Sun Sensors.2. Magnetometer, Sun Sensors & Rate Gyros.3. Horizon Sensor, Sun Sensors & Rate Gyros.4. Horizon Sensor, Magnetometer & Rate Gyros.5. Horizon Sensor, Sun Sensors, Magnetometer & Rate Gyros.
Actuators
1. 3 x Magentorquers.
2. 3 x Magnetorquers + 3 x Momentum Wheels.
3. 2 x Magnetorquers + 1 x Momentum Wheel.
4. 3 x Magnetorquers + 1 x Momentum Wheel.
Control structureControl structure
Interface to CDHS
1. Receive NORAD lines
2. Receive Time synchronization
3. Receive Control mode
4. Receive Solar panel info
5. Send Housekeeping
6. Send Alarms
Interface to CDHS
Mass budget
Magnetorquer(x3) 20g
mounting 5g
Momentum wheel 20g
mounting 5g
PCB+components 50g
Total……………………100g
Mass budget
Power budget
nominel peak
Magnetourqer 150 mW 150 mW
Momentum wheel 50 mW 200 mW
Actuator 20 mW 20 mW
Sensor interfaces 20 mW 20 mW
Total…………………… 240 mW 390 mW
Power budget