Patent ID: 6243006
Filing Date: 2001-06-05
Classification: E06B

Abstract:
A method for controlling the movement of a system component along a predetermined movement path defined by a component frame using an autonomous monitoring device that detects a position of said component and detects foreign objects in the movement path of the component to avoid an undesired collision, said monitoring device emitting a plurality of beams from transmitters to receivers, each beam being transmitted from a respective transmitter towards a respective receiver, the method including the steps of:arranging said transmitters and said respective receivers with respect to said system component frame so that the beams transmitted therebetween travel across or traverse the movement path of the system component to define a monitoring field;detecting the moving system component in the monitoring field according to the interruption of beams by said system component;assigning a status to each said beam according to whether said system component has interrupted the beam as the system component moves along the movement path, the portion of the monitoring field defined at least by the beams interrupted by said system component being a non-monitored partial region of the monitoring field and a remaining portion of the monitoring field having beams that have not been interrupted by said system component defining a monitored partial region;monitoring said monitored partial region of the monitoring field toward which the system component is moving, but into which the system component has not yet passed, to detect a foreign object in the movement path of the system component to avoid an undesired collision; andstopping or reversing the movement of the system component if a beam in the monitored partial region of the scanning field is interrupted.