Inverse Kinematics Solver C++

[sanket sane]

Hello, I am trying to use the Inverse Kinematics solver through the c++ API and I am wondering how to go about doing so since I am not an expert at c++ and I could not find any examples that use the Inverse Kinematics Solver.

Essentially, what I want to do is

1) Setup the solver with osim model and marker weights
2) Input the experimental markers 1 frame at a time (not altogether using a .trc file)
3) Solve for and get the optimized coordinates obtained from the solver

I have written some of the code but there may be missing/incorrect steps

Code: Select all

#include <OpenSim/OpenSim.h>
#include "OpenSim/Common/STOFileAdapter.h"
#include <ctime>  // clock(), clock_t, CLOCKS_PER_SEC
#include "IK_ID.h"

using namespace OpenSim;
using namespace SimTK;
using namespace std;


int main()
{
 
        
    
    // Create a new OpenSim model. 
    Model osimModel("C:/Users/sanke/Documents/gatech/RoboticsResearch/Arm_IK_ID3.osim");
    //set for marker weights
    Set<MarkerWeight> *marker_weights = new Set<MarkerWeight>();
    //marker trc file
    std::string marker_file("C:/Users/sanke/Documents/gatech/RoboticsResearch/OpenSim/4.1/Models/UpperArmPilot9/Session1/trial_feedback03.trc");
    //markers reference
    MarkersReference markers_experimental(marker_file, *marker_weights, Units(Units::Meters));
    //marker weights
    Set<MarkerWeight> marker_weights_exp = markers_experimental.upd_marker_weights();
    marker_weights_exp.insert(0, MarkerWeight("RSHO", 1));
    marker_weights_exp.insert(1, MarkerWeight("RELB", 1));
    marker_weights_exp.insert(2, MarkerWeight("RELA", 1));
    marker_weights_exp.insert(3, MarkerWeight("RUPA", 1));
    marker_weights_exp.insert(4, MarkerWeight("RWRB", 1));
    marker_weights_exp.insert(5, MarkerWeight("RWRA", 1));
    marker_weights_exp.insert(6, MarkerWeight("RFRM", 1));
    //coordinate reference (should be empty)
    SimTK::Array_< CoordinateReference > coordinate_reference;

    //Create solver
    InverseKinematicsSolver solver(osimModel, markers_experimental, coordinate_reference);

    //initialize system
    SimTK::State si = osimModel.initSystem();

    //solve
    solver.assemble(si);
    solver.track(si);
        
    // End of main() routine.
    return 0;
}

[Thomas Uchida]

Example code can be found in the "testInverseKinematicsSolver.cpp" file on GitHub: https://github.com/opensim-org/opensim- ... Solver.cpp. It looks like there are test cases that will get you most of the way there.

[sanket sane]

Ok thanks, that should help. I didn't realize it was there.