A RELIABILITY APPROACH TO EVALUATING ROBOT ACCURACY PERFORMANCE

Abstract

The capability of a robot to position its end-effector with accuracy is an important attribute for advanced robots in industrial automation technology. This study aims to assess positioning accuracy of robot end-effectors using reliability approaches. The reliability provides a statistical means for representing robot accuracy. Both the linear regression and iterative Taylor series methods are used to deal with limit states in reliability calculation. The proposed iterative Taylor series method improves computation accuracy compared with the prior literature. Both computer simulations and experiments were conducted to verify the performance of the accuracy assessment method. Examples show that the positioning accuracy is sensitive to tolerances of arm length and actuating accelerations. More important, dynamic errors, in comparison to geometric and kinematic errors, influence accuracy significantly.