Search found 1375 matches

by jimmy d
Thu Dec 05, 2019 7:21 am
Forum: OpenSim
Topic: CMC
Replies: 1
Views: 416

Re: CMC

Those file sizes seem very large. How long are your experimental trials? If you have a very long experimental trial, then you may want to break it up into a number of smaller trials to help with analysis.
by jimmy d
Thu Dec 05, 2019 7:11 am
Forum: OpenSim
Topic: how to measure the bushing force
Replies: 4
Views: 861

Re: how to measure the bushing force

You can run an analysis that includes a force reporter. The force reporter can output the bushing forces.
by jimmy d
Thu Dec 05, 2019 7:07 am
Forum: OpenSim
Topic: Knee tracking problem when using patellar coordinate coupler constraint
Replies: 2
Views: 570

Re: Knee tracking problem when using patellar coordinate coupler constraint

Are the errors reported in degrees? As in-- the peak error you are seeing is ~0.055 of a degree?
by jimmy d
Thu Dec 05, 2019 7:02 am
Forum: OpenSim
Topic: Design a new model
Replies: 1
Views: 213

Re: Design a new model

The OpenSim WIki is a good place to start. There are also some good papers out there to read, including the this one.
by jimmy d
Tue Nov 26, 2019 3:35 am
Forum: OpenSim
Topic: Scaling in Matlab
Replies: 2
Views: 497

Re: Scaling in Matlab

The API for many Classes (like the ScaleTool) were changed between 3.3 and 4.0 since it was such a major release. You can view the API documentation for the ModelScaler, here . In 4.0, there is also a new run() method on ScaleTool , reducing the requirement to process the model in the ModelScaler or...
by jimmy d
Sat Nov 16, 2019 9:57 am
Forum: OpenSim
Topic: question regarding SO
Replies: 4
Views: 737

Re: question regarding SO

I would suggest posting a zip of all the files needed to recreate the issue. It could be poor kinematics, forces, model scaling, muscle scaling.
by jimmy d
Sat Nov 16, 2019 9:16 am
Forum: OpenSim
Topic: question regarding SO
Replies: 4
Views: 737

Re: question regarding SO

If you haven't yet, perhaps have a look at that Static Optimization tutorial , it discusses jagged activations. There also could be discontinuities in either your kinematics or, if the jumps are around heel strike or toe-off, due to the forces (thus accelerations) changing suddenly. There have been ...
by jimmy d
Sat Nov 16, 2019 8:00 am
Forum: OpenSim
Topic: Exporting IMU Data from C3D files.
Replies: 5
Views: 697

Re: Exporting IMU Data from C3D files.

I started a new topic for your issue because it wasn't related to the original thread. You should check the MVN documentation and reach out to Xsens user support. Xsens can output the raw IMU data in txt file format and that is what the OpenSim IMU data converters. Otherwise, you will have to write...
by jimmy d
Fri Nov 15, 2019 3:29 pm
Forum: OpenSim
Topic: OpenSim 4.0 Scaling Error
Replies: 2
Views: 380

Re: OpenSim 4.0 Scaling Error

You may want to start with the markers-- all of your markers are connected to "ground" and not to model bodies.
by jimmy d
Fri Nov 15, 2019 9:06 am
Forum: OpenSim
Topic: Why Minimum activation cannot be less than 0.01 for Thelen2013 muscle?
Replies: 1
Views: 418

Re: Why Minimum activation cannot be less than 0.01 for Thelen2013 muscle?

Details about the modeling choices for the Thelen2013 muscle can be found here. The choice of default values, like minimum activation, were choosen to reduce numerical singularities.