<t>Hi Adam:<br/> <br/> SDFast is a great and reliable multibody dynamics solver and its speed is quite difficult to match. But, it is a commercial product and not open source and therefore not extensible. Simbody is open source and freely available. The biggest advantage of Simbody is the ability to...

<t>Hi Simon:<br/> <br/> All the muscle points are in the .osim model file and are defined to the body to which the are attached. If you want to get the trajectories of these points during a simulation, you can add a "PointsKinematics" in the "Analyze" (under the Tools menu).<br/> <br/> Under the Ana...

<t>Hi Jesal:<br/> <br/> OpenSim assumes X to be fore(+ve)-aft, Y to vertical(+ve up) and Z to be medio-lateral. This assumption is necessary because of how ground reactions forces are applied to the model and some other issues.<br/> <br/> The easiest solution is NOT to recollect your data but to sim...

<t>If the forces look good (i.e. applied at the correct location and in the correct direction), then we would not suspect the motion file to be the problem. Under the external loads tab, for the inverse dynamics tool, double check that the forces are in fact being applied to the corresponding calcan...

<t>Apologies for the delay.<br/> <br/> A flow sheet is a very good idea.<br/> <br/> At what stage are things breaking down- scale, inverse kinematics? If in IK, we have a known bug in 1.0 that the IK Anaylsis Tool is not correctly writing out the setup file (missing an importnat tag) when it is crea...

<r>Currently, it is not possible to read a c3d motion file directly into OpenSim. This is a popular feature request that we hope to add to OpenSim in a future release. However, we currently do not have a specific timeline for when this feature will be made available. For now, it is the user's respon...