Numerical Solution Approach for the ROBOTIS OP2 Humanoid Hand Inverse Kinematics

Abstract

Small-size humanoids are widely used in human-robot interaction (HRI) projects and activities. To operate robot limbs in HRI and pick-and-place tasks it is required to solve an inverse kinematics problem. Classical approaches are closed-form solutions with algebraic or geometric approaches or a numerical solution. While a typical numerical solution is supposed to search for joint variables using an iterative optimization, in this paper we suggest an off-line solution for a ROBOTIS OP2 humanoid upper limb via a forward kinematics approach that allows to calculate in advance all possible solutions for an end effector pose within a robot workspace with several levels of the workspace discretization. The solution was obtained in a simulation and successfully validated with a real ROBOTIS OP2 humanoid.