Platform for Attitude Control...
Transcript of Platform for Attitude Control...
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PACE Platform for Attitude Control Experiment
Jiun-Jih Miau and Jyh-Ching JuangNational Cheng Kung University
Tainan, TAIWAN
PACE website: www.iaalab.ncku.edu.tw/pace/
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Introduction Significances of cubesat researchCubesat research in Taiwan
NSPO: YAMSAT (2001-2002)NCKU: PACE (2003- )
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PACE FeaturesMass: Less than 2 kg Dimension: 100 x 100 x 200 mmADCS Requirement : 3-axis stabilizationPayload: MEMS temperature sensorDual on-board CPUsTCS: Passive thermal controlOperating Orbit (TBD):
Near-circular orbit 600 km , inclination 98ºTT&C: Amateur Radio Communication;
Up/Down link: 433MHz , Data Rate: 1200bpsCW: 144 MHz band
Power: Body mount solar array & Li-ion batterySatellite Life Time 2 months Launch Scheduled 2004-2005
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Characteristics of the PACEA double cube design Three-axis stabilization for pico-satellites
Momentum biased wheel + magnetic coilSensor suite integration for attitude determination:
magnetometer, gyro, coarse sun sensorTwo CPU design
8051-based CPU: C&DH and ADCSMEMS sensor technology demonstration
Temperature sensorCoarse sun sensor
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PACE OrbitOrbit altitude = 600 km, inclination = 97.79ºPeriod = 96.69 min, mean contact duration = 657sec
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PACE PayloadPACE payload: MEMS sensor
Temperature sensorCoarse sun sensor
Coarse sun Coarse sun sensorsensor
TemperatureTemperaturesensorsensor
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PACE Configuration
CW
C&DH
ADCSEPS
TT&CCoil
Magnetometer
Gyro sensor
X
Y
Z
Wheel
Battery
Antenna
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System Diagram
C8051F020
CPU
Internal A/D
TT&C
CW
Transceiver
Tx (DIO 1 bit)
Tx (UART)
Rx (UART)
PTT (DIO 1 bit)
MEMS Temp. Sensor
Sensor
MU
X
EPS
Power Monitor
Power Controller
ADCS
ADCS
CPU
Momentum Wheel
Coil Magne- tometer
CMD (DA)
F/B (AD 12 bit)
TXRX External RAM
C&DH Kill SwitchAntenna Dep.
Gyro Coarse
SunSensor
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EPS
DRU
Solar Cells
Batteries
12V
5V
Momentum Wheel
Magnetometer
OBCSlave OBC
ModemCW
Payload
Magnetometer
Gyro
Coils
EPSTransceiver
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PACE Operating Mode
Boot/Reset Mode
Normal Mode
Power Monitor Mode
Boot Complete
Ground Test Mode
(Idle)Remove
Before Flight On
Bit error occurred
No Contact > N days
Power On
Low power
Charge completed
Contact ModeGround Command
Max Contact Time Exceed
Launch Mode
Safe Mode
Initial & 3-Axis Mode
Low Power
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Momentum WheelA momentum wheel is developed for the 3-axis control of the PACE.
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PACE ADCS
Attitude DeterminationAttitude DeterminationKalmanKalman filterfilter
GyroGyro
S/C DynamicS/C Dynamic Disturbance Disturbance TorqueTorque
Attitude Control Attitude Control SystemSystem
Coarse Sun Coarse Sun SensorSensor
ω_Body Φ, θ, Ψ
ω_estimated
Θ_estimated
Θ_measuredω_measured
MagnetometerMagnetometer
B_Body
Orbit informationOrbit information
IGRF ModelIGRF Model
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SummaryTaiwanese Cubesats
Cubesat YAMSAT PACE
Development 2001-2002 2003-Developer NSPO NCKU
Size/Weight Single cube, 1 kg Double cube, 2 kg
Technology demonstration
system engineering
3-axis control
C&DH One CPU Two CPUs
Payload Microspectrometer MEMS temp sensor
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Thank you