Patent ID: 6204764
Filing Date: 2001-03-20
Classification: G06K,G07B,G07C,G08B

Abstract:
An object tracking system for tracking the removal of objects from a storage unit and the replacement of the objects at a storage unit, said object tracking system comprising:a panel disposed in said storage unit, said panel being formed with openings defining a plurality of receptacles for receiving objects to be tracked;a backplane in said storage unit;an ID tag attached to each of the objects to be tracked, each ID tag including electronic storage means carrying a stored code associated with the object corresponding to the ID tag, each of said ID tags transmitting its stored code when said ID tag is appropriately activated;said plurality of receptacles in said panel being configured to receive objects when objects are replaced in said storage unit and to allow the objects to be selectively removed from the storage unit;a sensor associated with each of said receptacles for activating the ID tag of an object in said receptacle and detecting the resulting transmission by the ID tag of the stored code associated with the object, said sensors being supported on said backplane;selection circuitry coupled to said sensors for successively selecting said sensors, each sensor, when selected, detecting the stored code associated with an object if an object is present in the corresponding receptacle and detecting no code if an object is not present in the corresponding receptacle;a controller coupled to said sensors for receiving stored codes detected by said sensors and for determining, based on the received codes, the absence of objects removed from the storage unit and the presence and location within the storage unit of objects present at the storage unit;each of said ID tags comprising a radio frequency identification (RFID) tag, the stored codes of said RFID tags being transmitted through radio frequency transmission;each of said RFID tags including an antenna for transmission of the stored code within the tag and each of said sensors including an antenna for receiving stored codes transmitted by RFID tags present in a corresponding one of said receptacles.