projet esmo - european students moon orbiter - cles-facil 2007
TRANSCRIPT
AOCS_A4
Reaction Wheels
Jean-Matthieu COUSIN
National Institute of Applied Sciences (INSA)
Lyon, FRANCE
European Student Moon Orbiter - Phase B workplan
Actual Design Workplan
Simulation
Conclusion
AOCS_A4 : Reaction wheels
Outline :
European Student Moon Orbiter - Phase B workplan
Dynacon Micro Wheel 1000
What do we have to do now ?
AOCS_A4 : Reaction wheels
Actual Design
Workplan
Simulation
Conclusion
European Student Moon Orbiter - Phase B workplan
Spacecraft : need different
attitudes
AOCS :
Sensors
software
MRW
AOCS_A4 : Reaction wheels
Performance Requirements : Assure pointing accuracy during Imaging mode (NAC) Maintain attitude for communications with lunette during
subsatellite mode without any help from the thrusters
Lifetime Requirements : Required delta-V momentum offloading should not
exceed the propellant mass budget of the Attitude Control Thrusters for a 10 months mission.
Configuration Requirements : Provide a full 3-axis control Minimize power drain while maintaining redundancy Include angular rate and temperature sensors Allow ease of integration in the Spacecraft
European Student Moon Orbiter - Phase B workplan
Actual Design
Workplan
Simulation
Conclusion
Workplan
Actual Design
AOCS_A4 : Reaction wheels
Simulation
Actuators selected : with a worksheet validation
Dynacon MicroWheel 1000
• Moment storage capacity :1.1 N.m.s
• Power consumption : 10 W max (9W +1W)
• Speed range : +/- 10,000 RPM
• Max Torque : 30 mN.m
• Size : 129x 129x 88,5 mm
• Mass : 1.3 kg • Include angular rate and temperature sensors
Conclusion
European Student Moon Orbiter - Phase B workplan
WARNING!!!Is it sufficient with the current configuration?
Actual Design
Workplan
AOCS_A4 : Reaction wheels
Simulation
Conclusion
European Student Moon Orbiter - Phase B workplan
Objective :
Update the Excel WorksheetAnd check the MRW1000 with the current configuration.
Requirements :
SPEC from AOCS_A1and the former requirements
Tools :
EXCEL
Comments : Try with the STRU team to perfectionate the Worksheet to add the new inertial data more easily.
Actual Design
Workplan
AOCS_A4 : Reaction wheels
Simulation
Conclusion
European Student Moon Orbiter - Phase B workplan
Objective :
Requirements :
Tools :
Comments :
Put forward a partnership with INSA and build our own Wheels.
We need to increase our team, about to be highly capable in different subjects as electronic, software…
SPEC from AOCS_A1and the former requirementsEPS requirements
…
Actual Design
Workplan
AOCS_A4 : Reaction wheels
Simulation
Conclusion
European Student Moon Orbiter - Phase B workplan
Objective :Decide which kind of electronic components we need, which kind of interfaces…Requirements :
Tools :
Comments :
SPEC from AOCS_A1and the former requirementsOBDH and EPS requirements
It’s a major problem that we have to resolve. (for OBDH and EPS team)
…
Actual Design
Workplan
AOCS_A4 : Reaction wheels
Simulation
Conclusion
European Student Moon Orbiter - Phase B workplan
Objective :
Convert our model on Catia file
Requirements :
Tools :
Catia
Comments :
Should we use a specific version of Catia?
Requirements
Validation
AOCS_A4 : Reaction wheels
Conclusion
Actual Design
Performance requirements during Imaging mode :
Nadir pointing mode : countering disturbances while maintaining pointing accuracy
Solar Radiation Pressure Torque : 5.10-7 N.mGravity Gradient Torque : 7.10-7 N.m (worst case)
Max torque available : 3.10-2 N.mMomentum storage capacity allow us to
maintain attitude during 24 hours before using thrusters to off-load the wheels
European Student Moon Orbiter - Phase A review
Actual Design
Workplan
AOCS_A4 : Reaction wheels
Simulation
Conclusion
European Student Moon Orbiter - Phase B workplan
Objective :
Requirements :
Tools :
Comments :
Determine if a software is required or not? To convert inputs in voltage or intensity
OBDH requirements
Requirements
Validation
AOCS_A4 : Reaction wheels
Conclusion
Actual Design
Performance requirements during Imaging mode :
Nadir pointing mode : countering disturbances while maintaining pointing accuracy
Solar Radiation Pressure Torque : 5.10-7 N.mGravity Gradient Torque : 7.10-7 N.m (worst case)
Max torque available : 3.10-2 N.mMomentum storage capacity allow us to
maintain attitude during 24 hours before using thrusters to off-load the wheels
European Student Moon Orbiter - Phase A review
Actual Design
Workplan
AOCS_A4 : Reaction wheels
Simulation
Conclusion
European Student Moon Orbiter - Phase B workplan
Objective :
Requirements :
Tools :
Comments :
Make our simulation.
Simulation team requirements
Matlab, Simulink
We have to talk about the simulation with the team in charge of it.
Requirements
Validation
AOCS_A4 : Reaction wheels
Conclusion
Actual Design
Performance requirements during Imaging mode :
Nadir pointing mode : countering disturbances while maintaining pointing accuracy
Solar Radiation Pressure Torque : 5.10-7 N.mGravity Gradient Torque : 7.10-7 N.m (worst case)
Max torque available : 3.10-2 N.mMomentum storage capacity allow us to
maintain attitude during 24 hours before using thrusters to off-load the wheels
European Student Moon Orbiter - Phase A review
Actual Design
Simulation
AOCS_A4 : Reaction wheels
Workplan
Conclusion
European Student Moon Orbiter - Phase B workplan
Simulation :
Inputs :
• Torques we have to apply for each wheels.• Information from the ground station : unload
Outputs :
• Temperature (so we need a model to simulate the friction).
• The speed of each wheel
• The power consumption ?
Requirements
Validation
AOCS_A4 : Reaction wheels
Conclusion
Actual Design
Performance requirements during Imaging mode :
Nadir pointing mode : countering disturbances while maintaining pointing accuracy
Solar Radiation Pressure Torque : 5.10-7 N.mGravity Gradient Torque : 7.10-7 N.m (worst case)
Max torque available : 3.10-2 N.mMomentum storage capacity allow us to
maintain attitude during 24 hours before using thrusters to off-load the wheels
European Student Moon Orbiter - Phase A review
Actual Design
Simulation
AOCS_A4 : Reaction wheels
Workplan
Conclusion
European Student Moon Orbiter - Phase B workplan
Simulation :
Structure : Nominal Mode Torque
Acceleration required
Rotation speed
Required speed
Power consumptionTemperature
New rotation speed
Intensity required
STEP ?Every minutes? + - ?
Requirements
Validation
AOCS_A4 : Reaction wheels
Conclusion
Actual Design
Performance requirements during Imaging mode :
Nadir pointing mode : countering disturbances while maintaining pointing accuracy
Solar Radiation Pressure Torque : 5.10-7 N.mGravity Gradient Torque : 7.10-7 N.m (worst case)
Max torque available : 3.10-2 N.mMomentum storage capacity allow us to
maintain attitude during 24 hours before using thrusters to off-load the wheels
European Student Moon Orbiter - Phase A review
Actual Design
Simulation
AOCS_A4 : Reaction wheels
Workplan
Conclusion
European Student Moon Orbiter - Phase B workplan
Simulation :
Structure : unload Mode
Order from ground : unload
Rotation speed required.
Intensity required
New rotation speed
Requirements
AOCS_A4 : Reaction wheels
Actual Design
Conclusion
Validations
European Student Moon Orbiter - Phase A review
Answering Questions…
Thank you for your attention