Kinematic Calibration of a 2-DOF Parallel Orientation Manipulator: Theory and Simulation Results

The objective of this work is the calibration analysis of a 2-DOF orientation manipulator, conceived for micro-orientation tasks inside a microassembly workcell. The proposed device is an overconstrained spherical five-bar mechanism, already widely studied in the scientific literature and known for being a simple but robust solution for the realization of robot wrists; its 5R parallel kinematics architecture allows a wide orientation workspace and good accuracy performances. The present paper sets the theoretical bases for the “geometrical calibration” of the PKM (Parallel Kinematics Machine) and discusses the first simulation results: the meaning of “geometrical calibration” is intended as the identification of the construction and assembly errors that affect the manipulator static accuracy.