Opensense: Custom IMUs

[Dhyey Parikh]

How do you create a new IMU mappings file for custom IMUs and not XSens IMUs? I am confused on where to start since I am using 10 sensors versus the 8 IMUs seen in the Opensense example provided with the source code for Python.

[Ayman Habib]

Hello,

The mapping file is not specific to XSens, it's tied to the format. If you use your own IMUs but create XSens format files then you should be good to go.
The mapping file itself maps names from data-collection to names on model so you can edit/create one as needed with names proper to your situation.

Hope this helps,
-Ayman

[Dhyey Parikh]

Thank you! Yes this really helps, I was confused as to whether or not the mapping file was tied with the XSens IMUs or just the format of the input data.

[Yau JunKing]

Hi! I have the same problem as you. Do you solve the problem?
I don't know how to convert the file format. Do you know the structure file of XSens and APDM?

[Dhyey Parikh]

Hi Yau!

So I circumvented the whole XSens and APDM file format issue by simply using my orientation data which was already in the quaternion format into a Time Series Quaternion Table (which I found through the OpenSim and Simbody documentation online) and then converting it to the STO orientations file as seen in the IMUDataConverter.py file example provided for the XSens data for Python.

Not sure if this helps, but I found it much easier than trying to get my custom IMU data into the right file format and you also don't have to use the XSensDataReader or the mappings file!

Dhyey Parikh

[Yau JunKing]

Hi Dhyey!
Thank you for answering! I'm going to try this next.
Good luck for you!
Yau Junking

[michela gardi]

Hi,
could you please advice if I can consider using any IMU in Open-sense and if so, what are the best steps to have data read into openSim?

[Ayman Habib]

Hi Michela,

As described above what OpenSense cares about is what data is available rather than the specific IMU. We need Quaternions which you can use directly programmatically if you have them (as Dhyey described), or if using files to write these files using the same format/layout as one of the supported formats (XSens or APDM).

Hope this helps,
-Ayman