Performance Analysis and Design Optimization of 5R Planar Parallel Robots

This paper addresses the dimension synthesis and optimization of planar parallel robots. The design problem for parallel robots in general is much more complex than their serial counterparts, due to the strong dependence of geometric parameters and their performances. In dimension synthesis, typical performance characteristics that may be considered to evaluate the fitness of a design include workspace, manipulability, velocity, stiffness, and payload. A case study on optimal design for both workspace and manipulability had been presented previously for a specific class of planar parallel robots with 5R joints. This paper extends the design optimization study to include the remainders for the same class of 2-dof robots. Analyses of individual performance characteristics relative to the velocity, stiffness, and payload properties will be presented first. A simple and yet effective parameter-variation-based method will be demonstrated to obtain various optimal design solutions corresponding to those characteristics respectively.