Assistance Required with Integrating Open-Source Datasets in OpenSim

[Elton Dmello]

Dear all,

I am currently working on a project that involves integrating open-source datasets with pre-existing models in OpenSim. However, I am encountering two issues:

1. When attempting to load .xml files for scaling, no output is generated.
2. When loading motion (.mot) and trajectory (.trc) files into a model, I receive the following error: "Could not associate motion to model."
I would greatly appreciate any assistance or guidance on resolving these issues.

Thank you in advance for your support.

Best regards,
Elton Dmello

[Nicos Haralabidis]

Hello Elton,

Have you tried going through the sections 'preparing your data' [1] and 'scaling' [2] of the user-guide?

[1] https://opensimconfluence.atlassian.net ... +Your+Data
[2] https://opensimconfluence.atlassian.net ... 00/Scaling

Best wishes,

Nicos

[Elton Dmello]

Hi Nicos,

I have thoroughly reviewed the user guide and followed the instructions carefully. The data I'm working with are open-source datasets, readily available online. Before converting them into the formats compatible with OpenSim (i.e., .c3d files to .trc and .mot, or .csv files to .xml), I did not modify any of the original files.

Despite this, I continue to encounter errors in MATLAB when using various OpenSim toolboxes to convert the .c3d files. I have also tried using an online converter to generate the .trc and .mot files, but even with those, OpenSim produces an association error when I attempt to apply motion to the musculoskeletal model.

Could these issues be caused by missing or incomplete data in the downloaded datasets?

Thank you for your assistance.

Best regards,
Elton Dmello

[Nicos Haralabidis]

Hello Elton,

Have you tried using the methods for converting C3D files to *.trc/*.mot files built into OpenSim?
https://opensimconfluence.atlassian.net ... .c3d+Files

Other available packages to do so can be found here:
https://opensimconfluence.atlassian.net ... otion+Data

Hope that helps!

Nicos

[Elton Dmello]

Dear Nicos,

Thank you for your response. However, despite following the steps outlined in the user guide, I am still unable to open open-source datasets in OpenSim using the generic Rajagopal model included in the OpenSim Library. The user guide only provides instructions for working with the examples that come with the OpenSim Library, but it does not specify how to simulate data from open-source datasets or the correct procedure to follow.

This brings up two questions:

1. Can open-source datasets be used with generic musculoskeletal models like those available in the OpenSim Library?
2. If so, what specific files are required in the dataset for successful simulation?

Currently, I am attempting to use data from the AnDyDataset, which includes c3d, mnvx, bvh, mvn and csv files along with a participant specification excel sheet.

Thank you for your assistance.

Kind regards,
Elton Dmello

[Nicos Haralabidis]

Hello Elton,

Did you take a look at the first link I shared in my previous comment? If you look at the section titled 'Reading C3D files through Matlab' it provides a code snippet for reading a *.c3d file and then converting it to the relevant files for usage with OpenSim (trc and mot).

[1] Open-source datasets can be used with OpenSim.
[2] Most motion capture system permit marker, force plate and EMG data to be collected synchronously and then exported to the c3d file format. To answer "what files are required in the dataset for successful simulation?" it very much depends on your research question. If you are studying walking and want to know the muscle forces based on an inverse approach then typically, at a minimum, you will require marker and force plate data.

Hope that helps!

Nicos