Changing the frame of reference

AI Thread Summary
The discussion centers on designing magnetorquers for cubesats, specifically the need to simulate the geomagnetic field in the cubesat's frame of reference. The user has geomagnetic field data in Earth's frame and requires it to be transformed to match the cubesat's body frame, which is in normal Cartesian coordinates and is not aligned with Earth's frame. Key questions arise about the relative velocity between the two frames and the alignment of their axes. The user expresses confusion about the necessary calculations for torque in this context. Clarifying these aspects is essential for progressing with the simulation and prototype development.
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I'm currently doing a student project at uni and I'm trying to design magnetorquers for cubesats.Before I make the prototype I need a simulation of what will happen.The problem is that for my calculations,I need to change the frame of reference of the geomagnetic field.So basically I need to go from Earth's frame of reference to the cubesat's frame of reference.I've been researching a lot and I haven't found much.Any suggestions that you might think will help?
 
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It's not clear what you're trying to achieve, eg whether this is about a velocity boost, a rotation, a change of coordinate type (eg spherical vs Cartesian), or some combination of the above.

What sort of coordinates are you using in the two frames?

Do the two origins have a nonzero relative velocity?

Are the axes of the two frames aligned?
 
andrewkirk said:
It's not clear what you're trying to achieve, eg whether this is about a velocity boost, a rotation, a change of coordinate type (eg spherical vs Cartesian), or some combination of the above.

What sort of coordinates are you using in the two frames?

Do the two origins have a nonzero relative velocity?

Are the axes of the two frames aligned?

Well I have the data for the geomagnetic field but it is in Earth's frame if reference.My magnetorquers are in body frame of reference so if I want to calculate the torque, I need to work in the same frame. Both of them are normal Cartesian coordinates. The are not aligned and the body frame is rotating in a given orbit. Sorry if the details are vague, but I'm so confused myself that I don't know what I should look for.
 
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