Skillful Operation of Working Plate Under Non-Uniform Loads with an Industrial Dual-Arm Robot Considering Power Consumption of Joints Motors

Abstract

With the advancement of the motion control of industrial robots in recent years, a method that can easily measure the accuracy of the synchronous control of a two-axis dual-arm robot is desired. Therefore, in this study, we propose a new measurement method that creates a ball rolling motion in a circular orbit on a work plate and uses the rolling motion error with respect to the reference circle. In addition, industrial robots in the field are always forced to operate continuously for a long period of time, and they work with all kinds of loads overlapping and applying non-uniform loads. In this study, we propose a new measurement method that creates a rolling motion of a ball on a circular track on a work plate and uses the error of the rolling motion relative to a reference circle. In particular, in order to elucidate the motion error during long-time continuous operation under high load, we approached the problem from the viewpoint of joint temperature and power consumption. As a result, we found that the ball trajectory error was caused by an increase in the temperature of the elbow and wrist motors, which increased the joint load and caused an angular error in the plate. Even when non-uniform loads were applied, the circular trajectory could be corrected by making corrections according to the temperature at each arm. The tendency of the angle error due to the temperature rise and the increase in joint load of each joint was found, and it was found that it was possible to correct the angle error by FF control.