Coppelia Kinematics Routines

The Coppelia Kinematics Routines is a collection of C++ functions that allow to solve forward/inverse kinematics tasks for any type of mechanism (redundant/non-redundant, containing nested loops, etc.). Those functions give CoppeliaSim its kinematics calculation capability.

You can embedd and use the Coppelia Kinematics Routines in your stand-alone application, which then can programmatically set up complex kinematics tasks. Refer also to the Coppelia Kinematics Routines C++ API documentation.

The Coppelia Kinematics Routines source code is not directly part of CoppeliaSim, and carries separate licensing conditions. Refer to the source code for details, and contact us.

Following is a simple example how to set up an inverse kinematics task, and perform calculations from within an external application:

#include "ik.h"

int main(int argc, char* argv[])
{
    // Create the IK environment:
    ikCreateEnvironment();

    // Create a simple 3 DoF kinematic chain:
    int tipHandle,targetHandle;
    int joint1Handle,joint2Handle,joint3Handle;
    ikCreateJoint(nullptr,ik_jointtype_revolute,&joint1Handle);
    ikCreateJoint(nullptr,ik_jointtype_revolute,&joint2Handle);
    C7Vector tr(C4Vector(1.57,0.0,0.0),C3Vector::zeroVector);
    ikSetObjectTransformation(joint2Handle,-1,&tr);
    ikSetObjectParent(joint2Handle,joint1Handle,true);
    ikCreateJoint(nullptr,ik_jointtype_revolute,&joint3Handle);
    tr.X=C3Vector(0.0,0.0,0.2);
    ikSetObjectTransformation(joint3Handle,-1,&tr);
    ikSetObjectParent(joint3Handle,joint2Handle,true);
    ikCreateDummy(nullptr,&tipHandle);
    tr.Q.clear();
    tr.X=C3Vector(0.0,0.0,0.4);
    ikSetObjectTransformation(tipHandle,-1,&tr);
    ikSetObjectParent(tipHandle,joint3Handle,true);
    ikCreateDummy(nullptr,&targetHandle);
    ikSetObjectTransformation(targetHandle,-1,&tr);
    ikSetLinkedDummy(tipHandle,targetHandle);
    // we now have: joint1 --> joint2 --> joint3 --> tipDummy <...> targetDummy

    // Create an IK group that constrains the chain tip to follow (in position)
    // the target dummy:
    int ikGroup;
    ikCreateIkGroup(nullptr,&ikGroup);
    int ikElementIndex;
    ikAddIkElement(ikGroup,tipHandle,&ikElementIndex);
    ikSetIkElementConstraints(ikGroup,ikElementIndex,ik_constraint_position);

    ikGetObjectTransformation(targetHandle,-1,&tr);
    while (true)
    {
        // Slightly move the target dummy:
        tr.X=tr.X+C3Vector(0.001,0.002,-0.0001);
        ikSetObjectTransformation(targetHandle,-1,&tr)

        // Solve IK:
        int result;
        ikHandleIkGroup(ikGroup,&result);
        if (result==ik_result_fail)
            break;

        // Read joint values:
        simReal joint1Angle,joint2Angle,joint3Angle;
        ikGetJointPosition(joint1Handle,&joint1Angle);
        ikGetJointPosition(joint2Handle,&joint2Angle);
        ikGetJointPosition(joint3Handle,&joint3Angle);
    }
    return(0);
}