Design, modelling, and implementation of a novel parallel end effector for robotic grinding

Abstract

Parallel mechanisms provide benefits like high stiffness and dexterity when used as robotic end effectors. This paper presents a novel redundant parallel end effector (PEE) with 3 degrees of freedom for robotic grinding of curved surfaces. The mobility, inverse kinematics, velocity analysis, workspace, motion force transmissibility and singularity of the PEE are systematically analyzed using the screw theory. The inverse dynamic model is established by combining the screw theory with the virtual work principle. Simulations are implemented to verify the accuracies of kinematics and dynamics models. An experimental platform is built and tests show the prototype can precisely track various trajectories. Grinding experiments on curved surfaces indicate significant improvement in surface quality. The experimental results verify the application potential of the designed PEE in the precision grinding of complex curved surface parts.