Parametric Tolerance Impact on Algebraic Position and Joint Torques of a Three Link Planar Manipulator using Evolutionary Techniques

Abstract

Tolerance analysis is a difficult task and an optimum tolerance allocation for individual parts is done to reduce the process error. This paper articulates the effect of changes in the link lengths due to manufacturing tolerance variation on the target path, assembly cost and joint torques of an R-R-R (three revolute joints) configuration planar three link robot manipulator. Genetic Algorithm (GA) and Elitist Non-dominated Sorting Genetic Algorithm-II (NSGA-II) are utilized to find optimum link lengths for the three link planar manipulator to minimize the errors. The analyses are further extended to identify the effect due to the three types of tolerances (fine, medium and coarse tolerances) on link lengths using C program codes and the results obtained from evolutionary algorithms are compared.