A Complete Closed-Form Solution to the Inverse Kinematics Problem for the P2Arm Manipulator Robot

In this paper, we propose a complete closed-form solution to the inverse kinematics problem for a 5-dof manipulator robot, where the existence conditions for all the possible solutions are clearly established and the "singular configurations" where infinite solutions exist are identified. We define a "desired configuration" for the final effector as the position for the center of the gripper and the direction of the gripper\´s main axis. This choice seems natural for robots mainly devoted to assembling tasks, even if the rotation around this main axis cannot be freely set. Under these conditions, a straight-forward method in order to obtain all the different exact solutions is also presented.