Human Perception of the Maximum Safe Speed of Robot Motions

Abstract

A laboratory experiment was conducted to determine the maximum speeds of robot arm motion considered by the subjects as safe for human operators working in a close proximity of the robot's working envelope. Twenty-nine college students (16 males and 13 females) participated in the study as monitors of the simulated assembly tasks performed by two industrial robots of different size and work capabilities. The results show that the speed selection process depends on the robot's physical size and its initial speed at the start of the adjustment process. Subjects selected higher speeds as “safe” if they were first exposed to the maximum speed of the robot, and significantly lower values when the initial speed of the robot's actions was only 5% of maximum. It was also shown that the subject's previous exposure to robots and the level of their knowledge of industrial robots highly affected their perception of safe speeds of robot motions. Such effects differ, however, between males and females.