Study on an Evaluation Process of the Robot Control Accuracy (1st Report)

Abstract

In the robot control, software servo system has been popular recently as a result of the micro computer performance improvement, and many control methods are proposed in the robot control. In the software servo system the motor position and velocity are controlled numerically with the quantization unit by position encoder and DA converter resolution for the velocity command. In addition, time is quantized as the sampling period. So it is necessary to evaluate the total control accuracy under such influences. Positional resolution has been examined minutely so far, as it concerns to the machining precision in the numerical control machine tool. But the influence of quantized velocity and sampling period has not been commonly examined. In this paper, Multivariable Root Mean Square criterion is proposed and applied to estimate quantitatively the control accuracy of the robot and examination of quantized velocity and sampling period is executed. and numerical method to evaluate by simulation is developed. The study was executed under the numerical simulation and the experimental results of real robot motion control.