Non-Convex Coordinate Transform Problem Rotating Frame

AI Thread Summary
The discussion centers on finding a coordinate transformation between a fixed frame (ƒ) and a rotating frame (ρ) using known 3D points and rotation angles. The challenge lies in determining the plane normal and distance in frame ƒ, as all points are coplanar but not identical across time. The user seeks to set up an overdetermined system using the plane equation in frame ƒ to solve the problem. Suggestions include utilizing concepts from Lorentz transformations to approach the solution. The overall goal is to clarify the problem and explore potential methods for approximation.
phil0stine
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I am sure this is not the best description of the problem, so let me know how I can clarify.

Say there are 2 coordinate systems, with one orbiting around the other. Call one fixed ƒ and the other rotating ρ. The goal is to find the transform between the two frames.

What's known is
1) A set of 3D points at a given time τ in frame ρ
2) The angle θ which frame ρ is subsequently rotated about the z-axis of frame ƒ between time τ and τ+1
3) New 3D points at time τ+1 in frame ρ, and so forth.
4) All points from all views lie in a single plane in frame ƒ (this does not mean the points at time τ and time τ+1 are the same, just that they are coplanar)

I want to set up the problem to use the plane equation in frame ƒ to solve an overdetermined system, but I run into the problem that I do not know the plane normal η and distance d in frame ƒ.

Is there any way this can be solved (even approximately)? Thanks
 
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I would start small and go from one dimension, then two dimensions to finally three dimension. A sketch would help a lot of understand the problem better.
 
phil0stine said:
I am sure this is not the best description of the problem, so let me know how I can clarify.

Say there are 2 coordinate systems, with one orbiting around the other. Call one fixed ƒ and the other rotating ρ. The goal is to find the transform between the two frames.

What's known is
1) A set of 3D points at a given time τ in frame ρ
2) The angle θ which frame ρ is subsequently rotated about the z-axis of frame ƒ between time τ and τ+1
3) New 3D points at time τ+1 in frame ρ, and so forth.
4) All points from all views lie in a single plane in frame ƒ (this does not mean the points at time τ and time τ+1 are the same, just that they are coplanar)

I want to set up the problem to use the plane equation in frame ƒ to solve an overdetermined system, but I run into the problem that I do not know the plane normal η and distance d in frame ƒ.

Is there any way this can be solved (even approximately)? Thanks
Lorentz transformations concepts can be used to solve the puzzle.
 
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