How to get all results of inverse kinematic computation?

[Gian-Hacher]

For one pose of the end effector, there may be more than one feasible configuration of the robot arm, but the function 'ik_xx' can only compute one of them. How to get all possible results through these functions?

[PhilFreeman]

The IK_xx functions are numerical methods to solve inverse kinematics. They converge on a single solution using gradient-decent-like methods. If you want to find "all" IK solutions (for certain manipulators and certain conditions there can be an infinite set of solutions) you can call the IK solver with multiple initial starting positions (q0) distributed across the configuration space. Each solver may find a solution. If there are a finite number of solutions, this will likely converge to that set of solutions. If there is an infinite set of solutions, the found solutions will lie on the self-motion manifold.