simtk.org

Hi,

I am trying to use IAA with Rolling constraint to reproduce the GRFs. As far as I understand from the article (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3993009/) and the opensim documentations (http://simtk-confluence.stanford.edu:80 ... +IAA+Works), knowing the estimation of GRF in the vertical direction and the kinematic of the body and its point of influence on the foot, one can estimate the rest of the components of GRFs in other directions, using the Rolling constraint method.

I have applied this method to the GaitModel2354, I get some results whose pattern matches well with the measured GRF but the values are far below the experimental measured one. Can anyone please give me a guidance where can be the problem?

Thank you,
Assal

It seems the results are provides per body mass.

using IAA provides muscle contributions to CoM and joints acceleration, and not to the GRFs. But you can calculate it from F=ma.
also, if the tag "<compute_potentials_only>" is true, they IAA provide muscle potentials (see the last paragraph in "How to Use IAA").