Identification and Compensation of periodic gear transmission errors in Robot Manipulators

Position and path accuracy are among the obstacles preventing robot manipulators to be more and more used for machining applications. Nonlinear joint errors are among different sources of error in robot positioning causing flactuational imperfections to a desired trajectory of TCP. In this paper we propose a novel method to identify and reduce the fluctuations in path of robot TCP resulting from the nonlinear behavior of joint transmission systems. This method is more time efficient compared to the rest of methods present in the literature. A practical example is presented in which we have reduced the fluctuation domain from 0.15(mm) to 0.09(mm) in an industrial robot arm.