Here is a set of files that run rra, update the mass properties, and write a new osim model. Main_rra.m sets up a Params structure that is passed along to runrra.m to setup and run the rratool thru the command line. Runrra also updates the model's COM position on the user defined segment. Then main_...

is it possible to analyze muscle contraction dynamics through some prescribed motion and prescribed muscle control? i've tried using the analyze tool and provided both a muscle controls file and a motion file. however, the muscle excitations just stay at their default values and don't change as pres...

My understanding is that RRA isn't trying to make the segment inertia correct but rather make them dynamically consistent, which can be achieved by changing the mass of each segment.

it sounds like the marker names from the TRC file does not match the marker names in the osim model. can you confirm that they are named the same?

it looks like the bodies are not being scaled (2nd tab in scale tool). What are the markers you are using for this?

i'm not clear on how opensim parses a trc file but I do see that the header info in your file uses .txt rather than .trc (row 1) and that the frame data are not integers. that might be causing some problems?

sounds like the input file isn't the appropriate format. can you post the TRC file you're trying to track?

some good references below. it might help the readers to understand more about your question and what you are testing with the model. lots of assumptions are required when modeling knee contact. Lerner ZF, DeMers MS, Delp SL, Browning RC. 2015. How tibiofemoral alignment and contact locations affect...

It looks like you are trying to run CMC with a knee that has unconstrained abduction but no contact or ligaments to provide stability in the frontal plane. Knees are stable because they have two condyles that can balance externally applied loads in the frontal plane. Any joint in opensim that does n...

can you share an example of the setup xml? Does the file have an absolute path? does the path have any space characters (i've found this to cause problems).