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For information on the latest version, please have a look at 1.33.5.

ikin (extension)

This function returns the joint position, among the 8 joint configurations, that corresponds to iSolutionSpace and is equivalent to the robot pose in task space.

Definition
DRFLEx.h within class CDRFLEx, public section

LPINVERSE_KINEMATIC_RESPONSE ikin(
    float fSourcePos[NUM_TASK],
    unsigned char iSolutionSpace,
    COORDINATE_SYSTEM eTargetRef,
    unsigned char iRefPosOpt
) {
    return _ikin_ex(_rbtCtrl, fSourcePos, iSolutionSpace, eTargetRef, iRefPosOpt);
};

Parameter

Parameter Name	Data Type	Default Value	Description
fSourcePos	float[6]		Target task location for six axes (TCP pose to be solved for).
iSolutionSpace	unsigned char		Solution space index (0-7) selecting one of eight IK configurations, or 255 to let the controller choose the reachable solution.
eTargetRef	COORDINATE_SYSTEM		Reference coordinate system for the TCP.
iRefPosOpt	unsigned char		Reference pose option. The function does not send this value to the controller, so every value gives the same result.

Return

Value	Description
LPINVERSE_KINEMATIC_RESPONSE	Extended inverse-kinematics response including the solved joint position (and related metadata).

Note

This call waits for the controller to answer.

The returned pointer refers to storage in the CDRFLEx object that other DRFL calls and every reconnect reuse; copy the structure before making another DRFL call. The 3-argument ikin returns its result in storage shared by all CDRFLEx objects in the process instead; see ikin. Except for get_user_home, the pointer is never NULL; do not use a NULL check to detect failure.

Example

float x6[6] = { 370.9f, 719.7f, 651.5f, 90.f, -180.f, 0.f };
LPINVERSE_KINEMATIC_RESPONSE res = drfl.ikin(x6, 2, COORDINATE_SYSTEM_BASE, (unsigned char)0);

float q[6] = {0};
for (int i = 0; i < 6; ++i) {
    q[i] = res->_fTargetPos[i];   // copy solved joints
}
drfl.movej(q, 60, 30);

This example solves IK for the TCP pose x6 in the BASE frame with solution space = 2 and ref-pose option = 0. The solved joint values are copied from res->_fTargetPos into q, then executed via movej(q, 60, 30) (velocity 60, acceleration 30). Use different solution spaces (0-7) to select another valid joint configuration for the same TCP pose.