Questions regarding the simulation of reaction wheels

[schaubh]

I have a question regarding the reaction wheels input message. In my simulation environment I have 3 different reaction wheels I want to control via 1 reactionWheelStateEffector. How exactly does the input message payload ArrayMotorTorqueMsgPayload work? It is an array with a length of 36.
What are all these entries for? How would I command my first reaction wheel with e.g.
torque of 1Nm with a stand-alone message?

Thank you for your time.

[schaubh]

Hello Claudio,

Individual reaction wheels are added to the state effector through its addReactionWheel() method. Each new call to this method stores the provided RW configuration data inside a C++ vector. The size of this vector determines how many reaction wheels are effectively controlled by this effector (N calls to addReactionWheel leads to the state effector keeping track of N RW, like one would expect)

This way, when a new rwMotorCmdInMsg of type ArrayMotorTorqueMsgPayload comes in, only the N first components of its motorTorque field will be read.

Now, assuming that you have set up a sufficient number of reaction wheels in the state effector, you are of course free to create a stand alone message of type ArrayMotorTorqueMsg with the corresponding elements of its motorTorque payload set to 1.

Hope this helps,

Ben

[schaubh]

Hello Benjamin,

Thank you for answering. Yes I added 3 reaction wheels to my spacecraft. So motorTorque[0] would be commanding the first reaction wheel? I guess my problem might be creating the stand alone message or the recording of the stand alone message.

Thanks for your help!

[schaubh]

motorTorqueMsgData.motorTorque[0] = 0.1
 print(motorTorqueMsgData.motorTorque[0])

This code prints out 0.0 in the console. I dont understand why. :(

[schaubh]

I got it working with

motorTorqueMsgData.motorTorque = [
       0.1,
       0.1,
       0.1,
   ]