A Robot Safety Experiment Varying Robot Speed and Contrast with Human Decision Cost
An industrial robot safety experiment was performed to find out how quickly subjects could respond to unexpected robot motion at selected slow robot speeds and how frequently they did not respond when a signal (an unexpected motion) should have been detected. The dependent variable in the experiment was the overrun distance beyond an expected stopping point that a robot arm traveled before a person actuated a pushbutton to stop the robot. A robotics technician risks being fatally crushed if a robot should trap the person against a fixed object. This risk can be reduced if, during programming and troubleshooting tasks, the robot is moving at a slow speed which gives the worker sufficient time to actuate an emergency stop device before the robot can reach the person. A General Electric P-50 robot was programmed to provide the experimental situation. Nine subjects were tested, all in the age range 20–30. The subjects were male volunteers, not currently working in a job involving robot programming or maintenance.