Dear OpenSim experts, For a project, I would like to estimate the passive joint torques during a passive (without muscle activity) sollicitation. Experimentally, we mobilize the ankle of a subject with an handheld dynamometer, and we measure the kinematics thanks to VICON. Thus, I am able to animate...

OpenSim computes the length of the muscle-tendon actuator from the geometric description of the muscle path and the pose of the model. Yes, indeed, and that's exactly what I want. For example, is it possible to know the function which compute the length of the bi-articular muscle, the gastrocnemius...

Dear OpenSim Experts, I'm using the Rajagopal's model, and I would like to know if there is a way to obtain the analytical expression of the function between the Muscle-Tendon Length and the joint angle. For instance, there is a way to obtain the detail of the function between the left semitendinosu...

Update : I finally suceeded to modify the geometry of my femur. I deplaced it along the Z-axis and it appeared to me that it did not change anything about the muscle-tendon units, which stay attached to the same points. (cf. Figure). So I better understand what I could read on the forum when OpenSim...

Dear OpenSim experts, I'm using Rajagopal model to simulate gait in children with cerebral palsy. In this population orthopaedic deformations can be present, for example, an excessive femoral anteversion/tibial torsion. These two properties are measured and known. Thus, I would like to know if there...

Hi Olesya,

I also would like to modify subject-specifically the bones of my OpenSim model. Since no answer was provided, I take the liberty of reviving this forum.
Have you finally succeed to visualize the modified model ?

Thanks in advance,

Regards

Hi Thomas, Thank you for your quick response. My run time is considerably reduced. :D musclelengths=zeros(1,num_timepoints); for t=1:num_timepoints for i=0:num_coordinates-1 %38 model.updCoordinateSet().get(i).setValue(state,Data(t,i+1),false); end model.assemble(state) model.equilibrateMuscles(stat...

Hi guys, Thank you for your responses and your codes. I am also interested in computing the MTU Length using the Matlab API with the Rajagopal's model. I succeeded to obtain the length of the semitendinosus tendon unit during a trial of a passive sollicitation of the knee, using this following code ...

Solution : I finally came to a solution. I misunderstood the "objects" class. In fact, you can cloneAndAppend only an object to an other one. So, the correct code lines are : M.getMarkerPairSet().cloneAndAppend(MP) and then, with the same logic, you can add your Measurement to you MeasurementSet : S...

Hi all, I'm new in OpenSim. I'm using the Rajagopal's model, and I animate it with a .mot file, corresponding to the joint angles previously computed in MatLab. The motion corresponds to a passive sollicitation of the knee using an handheld dynamometer. It seems to work, the motion is well reconstru...