A safety interlock system for a robotic apparatus includes a light curtain in combination with ultrasonic sensors to perform a staged interlock to reduce unnecessary alarms or shutdowns. A robotic apparatus, such as a linear travel-type robot system, is protected by a fixed light curtain for detecting...http://www.google.fr/patents/US5280622?utm_source=gb-gplus-shareBrevet US5280622 - Combined light beam and ultrasonic transducer safety sensing system
Combined light beam and ultrasonic transducer safety sensing system
