Global/Local Coordinate System Problems

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Sarah_M
Posts: 1
Joined: Thu Feb 21, 2019 8:28 am

Global/Local Coordinate System Problems

Post by Sarah_M »

Hello everyone,
i'm using Motive the first time. I want to track a mobile robot as rigid body. My question is: Can I transform the global coordinate system in the way, that the heigh is tracked by my Z-Coordinate and not by the Y-Coordinate?
Why do I get the same tracking data even though I use the global coordinate system in one case and the local coordinate system in the other case?
Do I understand correctly that the local coordinate system refers to the coordinate system of my rigid body (pivot point)?

Thanks for helping.
steven.andrews
NaturalPoint Employee
NaturalPoint Employee
Posts: 720
Joined: Mon Jan 19, 2015 11:52 am

Re: Global/Local Coordinate System Problems

Post by steven.andrews »

Hi Sarah_M,

Thanks for reaching out to the community regarding your questions.

Motive is inherently Y-up, and this cannot be changed. If you are streaming the realtime information, it is possible to change the streamed data to be Z-up. It is also possible to change the coordinate system when exporing to some file types.
https://v21.wiki.optitrack.com/index.ph ... Convention
https://v21.wiki.optitrack.com/index.ph ... ne#Up_Axis

For a rigid body, the local and global coordinate data will be the same. Local data is different for something like a bone segment, from one of the skeletons. When exporting local data, a skeleton's segment would be reported with its parent segment as the origin.

I hope this helps,
Steven
--
Steven Andrews
OptiTrack | Senior Customer Support Engineer
help.naturalpoint.com
support@optitrack.com
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