Optimization of a Redundantly Actuated Parallel Robot for Stirring Friction Additive Manufacturing

A novel Additive Friction Stir Deposition Robot is proposed, which is a rigid-flexible coupled redundantly actuated parallel robot designed for Stirring friction stir based additive manufacturing. The compliance of the robot is improved by designing a bidirectional cable-driven rod as the flexible branch chain of the mechanism. The degrees of freedom of the AFSDR are calculated, and the inverse kinematics model is established. Taking into account the geometric constraints in actual working conditions, the workspace performance of the moving platform is evaluated. The force/motion transmission performance indicators LTI and GTI based on the screw theory are computed. Finally, multi-objective optimization of the mechanism is accomplished using the NSGA-II algorithm, resulting in enhanced performance through comparative analysis.

Introduction

Aluminum alloy parts are widely used in various industries such as aerospace and marine due to their excellent corrosion resistance. One of the Additive Friction Stir is Additive Friction Stir Deposition (AFSD). It offers notable advantages including good flexibility and high additive efficiency [1], enabling the rapid integrated manufacturing of complex structural components from aluminum alloy. Consequently, AFSD hold great promise for future advancements.