Hi Mohammadreza, Thanks for the recommendation of the paper. I have also checked the paper, and I agree with Ton van den Bogert's point that according to the virtual work principle, equation 3 should be correct. I also notice that they have mentioned the analytical expression of the dl/dq is hard to...

Hi community, I am curious about how the OpenSim calculates the moment arm of muscles with wrapping surfaces. I somehow can not find the code or specific paper that mentioned a bit more details. Could someone guide me to the code or paper that may help me find it out? Thanks Best regard, Junnan Li

Hi all,

I am wondering if there is a tool/function that can convert an osim model to a urdf model? maybe only the kinematic and inertia properties excluding the muscles and constraints.

Best,
Junnan

Hi, as I understand, you are able to extract the Jacobian from Simbody. To truncate the full Jacibian matrix, you only need to know the column indexes of the coordinates that you are forcing. Check out the function Model.getCoordinateNamesInMultibodyTreeOrder to get the correct order of coordinates ...

Great! this is exactly the function that i am looking for. I have another problem regarding the coordinate setting. As I understand, once I create a joint to connect two adjacent bodies, I can define (or not define) the associated coordinates of that joint. The defined coordinates and their velocity...

Hi everyone, I have a problem when I use 'calcFrameJacobian()' to calculate the Jacobian matrix in MATLAB API. It seems that the coordinate indexes from the CoordinateSet are different from those of the SimbodyMatterSubsystem. For example, I import a hand model with all fingers and calculate the Jac...

I write a script to build a hand model using the Conditional Path Point (ConditionalPathPoint()). It runs ok at the first time but crashes without any reports when it runs again. I presume it is caused by the JAVA memory limit or something. Is it possible to build conditional path point without usin...