Hybrid Position-Orientation Decoupling in Robot Manipulators

Abstract

Kinematic decoupling in robotic manipulators implies that there is a subset of joints primarily responsible for the completion of a subset of the manipulator task. In this paper, we take a general view of kinematic decoupling in which we identify link subsystems primarily responsible for completion of a hybrid combination of both position and orientation. Our analysis leads to the discovery of decoupled manipulator geometries, for which closed-form inverse kinematic solutions are guaranteed. Kinematic decoupling also implies singularity decoupling wherein singularities of decoupled subsystems are equivalent to the manipulator singularities. The analysis leads to another method for identifying the singularities and solving the inverse kinematics problem of six-axes, serial-chain manipulators with decoupled geometries. The practicality of the concepts introduced is demonstrated through an industrial robot example involving a hybrid position and orientation decoupling.