Maintenance of Safety in Man-robot Co-working Operations by the Highlighted Area Method

Abstract

The problem of safety restrains spreading of man-robot co-working technologies. The paper investigates the applications in which staff works in robot work area. They include repairing, testing and adjustment procedures of technological equipment, manipulator and its programme of functioning. Particularity of these operations consists in frequent changing of operator activity points and the need to watch result of robot motions in close proximity to equipment, part or attachment fixed in manipulator jaws. Highlighted workspace method is one of the way to ensure the safety of worker. The method consists in restriction of robot movements in man working area. It can be realized by standard technical equipment such as mechanical enclosing structures, electronic access systems and light curtain devices. The investigation shows that they are not convenient in use because are not adapted for operational borderline changing. The comparison shows that systems which based on technical vision are better suited for such applications. They give more additional information to robot control system for flexibility selection of preprogrammed behavior when borderline intersection is detected. Highlighted workspace method includes two phases: marking of borderline between working areas and monitoring to prevent line intersection by robot or man. The means of borderline marking should support operative changing of borderline, simple teaching procedure of system technical vision and reliable detection in valid level of illumination. To satisfy above conditions special modules with blinking led lamps were developed. The paper describes procedure use of modules and gives results on detecting of their location in different brightness of backlighting.