Frames and origin in SO2 Manifold

AI Thread Summary
The discussion revolves around a robot equipped with a 3D laser scanner that rotates about two axes to collect data, with one axis allowing full rotation and the other limited rotation. The user seeks to understand how the distribution of points collected by the scanner changes when the origin is shifted to a new location, particularly in the context of the SO2 and SO3 manifolds. There is a suggestion that using the properties of these manifolds could simplify the transformation calculations needed for this shift. Confusion arises regarding the transition between SO2 and SO3, indicating a need for clearer explanations and examples. Overall, the user is looking for resources and collaboration to better grasp the mathematical concepts involved.
benzun_1999
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Hi

I am working on a robot that has a spinning 3D laser scanner. It rotates about two axis and collects data. In one axis it has full 3D rotation and in another axis it has limit rotation.

Now the read world points collect by this laser scanner is not unifomaly distributed but if parametreized in the SO2 manifold it will be uniform. Now if was in another point on the robot the points that i observe will be distributed different. Is there a way to understand how the points will be from this new location?

I am new to manifolds. I don't know if i explained the problem correctly. Can anyone point me to a book, idea, notes that can help me understand this. If you are interested I can try explaining more about it and would like to collobrate.

Thanks,
Benzun
 
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Honestly, I don't exactly know what you mean. You are a little vague on your details.

##SO_2(\mathbb{R})## is a very "nice" manifold (in fact, group) to work with because it has a lot of structure on it. I'm sure we can help somehow if you give us a better description of your problem.
 
Yes. I can explain you more. I know very litte about topology and manifolds.

A rotating laser basically rotates about two axis and generates a response for every angles so in SO2(R).

If you watch that video the white line is the scan generated at every instand of time. The scan itself is composed of points obtained by rotation about another axis.

So all the points are sampled uniformly in this space. Now I need to move the origin of scan to another location in the world and find the relationship between the original scan and the new points after shifting the origin.

Using ecludean geometry i can do it but since i am sampling the world in SO3 I feel it might be faster and easier to compute the transform that occurs due to change in orgin more accurately and easily if i solve it in SO3 manifold.
 
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benzun_1999 said:
Yes. I can explain you more. I know very litte about topology and manifolds.

A rotating laser basically rotates about two axis and generates a response for every angles so in SO2(R).

If you watch that video the white line is the scan generated at every instand of time. The scan itself is composed of points obtained by rotation about another axis.

So all the points are sampled uniformly in this space. Now I need to move the origin of scan to another location in the world and find the relationship between the original scan and the new points after shifting the origin.

Using ecludean geometry i can do it but since i am sampling the world in SO3 I feel it might be faster and easier to compute the transform that occurs due to change in orgin more accurately and easily if i solve it in SO3 manifold.

I apologize, but I am slightly more confused now. In the video, it looked like several white lines were being used. Also, you switch from saying "SO2" to "SO3." Your wording is slightly confusing.

I'm not an expert, but I'm going to guess that the scan from the new origin will overlap with the one from the original origin. Could you demonstrate what you are trying to say?
 
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