Sensing Techniques for Detecting Worker Presence within Robot Work Zones.
Sensing techniques for detecting the presence of workers within robot work zones were discussed. Projected trends indicated that because the industrial use of robots is increasing, an increasing number of workers will need protection while working in close proximity to robots. Although safety devices used on traditional machines were being adapted for use at robot work stations, it was felt that using safety sensor devices that set up three dimensional zones of protection that conform more closely to the movements of a robot might permit greater flexibility in performing human tasks near the robot. Perimeter protection and work zone protection were discussed. Fencing in robots was the simplest approach; however, this approach was only appropriate when robots worked with minimal human intervention. Perimeter safety methods offered no protection if a robot remained energized or was restarted after the perimeter had been entered. Sensing principles including capacitive, ultrasonic, and machine vision were discussed. A three level sensing system for robotized work stations developed by the Mechanical and Aerospace Engineering Department, West Virginia University, as part of the NIOSH program in industrial robotic safety was discussed. The system provided three levels of protection utilizing a light curtain, a safety mat, and an ultrasonic sensor on the robot. Responses to worker intrusion included flashing lights, auditory warnings, and reduction of robot speed or halting of work relative to the level of intrusion.
NIOSH-Author; Occupational-health; Industrial-safety; Automation; Workplace-studies; Safety-research; Equipment-design; Accident-prevention;
The Changing Nature of Work and Workforce, Proceedings of the Third Joint US-Finnish Science Symposium, Frankfort, Kentucky, October 22-24, 1986, NIOSH, Cincinnati, Ohio