Discussion and Support for the OptiTrack, SmartNav and TrackIR brands by NaturalPoint

Remote trigger of Motive with Labview and Python Client

NatNet, VRPN, TrackD, and Plugins

by adrianaoliva » Sat Nov 11, 2017 3:58 am

I am trying to create a remote trigger of Motive in NatNet SDK with Labview via the Python Client in order to syncronize data from Motive and Labview.

The first problem that I am having is that, if I use the Python Client Sample provided by NatNet SDK it gives me the following error:
Code: Select all
rot = Quaternion.unpack( data[offset:offset+16] )
struct.error: unpack requires a buffer of 16 bytes

I've read that it may be because of the direct depacketization that is using Python Client and that I have to update the parsing routines of the bit-stream packet syntax. The thing is that I don't know how I can do it. Anyone can help me? :cry:

I am relatively new at programing and I have no knowledge of C.

Thank you!!
Posts: 2
Joined: Fri Nov 03, 2017 4:22 am

by ryanhaun » Mon Nov 13, 2017 3:30 pm

Hi Adriana,

It looks like the error is coming from the assignment to "rot", which appears to not be a buffer of 16 bytes. Try making that change to see if your issue is resolved.

Kind Regards,
Ryan Haun
OptiTrack Support
NaturalPoint Employee
NaturalPoint Employee
Posts: 6
Joined: Tue Dec 27, 2016 11:11 am

by adrianaoliva » Tue Nov 14, 2017 3:16 am

i am not able to get the correct data from motive 2.0 and the python example script.
i am using the latest natnet sdk.

can we do a teamviewersession ? i am sure you can solve this issue very quickly.
Posts: 2
Joined: Fri Nov 03, 2017 4:22 am

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