Loading Motions

[Catherine Scarbrough]

My issue is that the OpenSim system will not load motions into the models. I was trying to load my own motion files into OpenSim which did not work. Then went back to the tutorials, and even the motion files in the tutorials would not work. The error given in OpenSim was that it "Could not associate motion to current model". This being said I used the motions that were associated to each model in the tutorials, but it still gave me an error in OpenSim.

[Dimitar Stanev]

Can you name the files and the model that you try to use and how you load the motion? It possible that you are trying to visualize .mot files related to ground reaction forces or .trc files that are not motion files. The last two can be visualized through File->Preview Experimental Data.

[Ayman Habib]

Hi Catherine,

As Dimitar pointed out, the ability to use a specific data file with a model depends on the contents of the file:
- If the file contains some coordinate values (hand-made or resulting from simulation for example) then you can load the motion directly and it will be associated to the model and animated.
- If the file contains data that changes over time but no coordinate values (e.g. ground reaction forces or marker data) then you can either view it as raw data (File -> Preview Experimental Data), or in case you have a motion loaded already, you can associate the data with the motion and they will be time synchronized.

Hope this helps,
-Ayman

[Catherine Scarbrough]

So the one that I am trying to load at the moment is using the 3DGaitModel2392 and loading the motion subject01_walk1_grf.mot while is located in the same file as the model. It continues to give me the same error when I try to load this motion to the model.

[Dimitar Stanev]

The file subject01_walk1_grf.mot does not contain the model's angles, but the ground reaction forces (grf). You can visualize the content of this file with File -> Preview Experimental data. If you want to load the joint angles in the model, then you have to use the file subject01_walk1.mot (or IK = inverse kinematics).