Real-Time Tracking System Based on RFID to Prevent Worker–Vehicle Accidents

In this letter, a radio frequency identification (RFID)-based location and tracking system that uses receiver signal strength (RSS) measurements is presented. The system is intended to be deployed at industrial scenarios or warehouses involving heavy machinery and vehicles in motion such as forklifts, and/or low visibility areas, aiming at preventing accidental collisions with workers. For this purpose, RFID tags are attached to helmets of the workers. The UHF reader antennas are located in the vicinity of the area where the workers are creating a coverage area where workers close to the vehicle can be detected and tracked. To deal with the propagation effects that degrade the RSS values, a propagation model based on on-site measurements together with an accurate characterization of the radiation pattern of the RFID reader antennas has been proposed. Validation with measurements in an scenario resembling the industrial environment is presented.