1. A robot safety system comprising: a robot having a plurality of mobile components, each instrumented with a plurality of proximity sensors adapted to develop a respective intrusion detection zone substantially surrounding said mobile component, each sensor adapted to detect an intrusion into a respective portion of the zone; a model of at least one predefined robot application comprising, for each of the intrusion detection zones, a set of accepted intrusions during each of a plurality of predefined time intervals comprising the application; a controller adapted to: control the robot to execute the application; during each time interval of the application, monitor for detected intrusions into each of the intrusion detection zones; and trigger an interrupt of the application in response to a detected intrusion into any one of said intrusion detection zones not in the set of accepted intrusions for said one intrusion detection zone for the respective time interval.