RFID-based location-sensing system for safety management
This paper focuses on an active radio frequency identification (RFID)-based location-sensing system for enhancing the workers safety under a cargo crane in a steel industry. For the purpose, the time of flight (TOF)-based distance sensing RFID system with location trilateration algorithm is developed to monitor workers position. However, RF signal is easily affected by the surrounding environmental conditions, it is difficult to obtain reliable positional information under the restricted environmental conditions of the crane. For the problem, this paper introduces two new improvements. Firstly, circular polarization antennas are developed, which is highly effective for reducing an error in the distance estimation by transceiving RF signals with less dependance on its orientation. Secondly, a three-dimensional location-sensing algorithm that facilitates a distance and position filter is developed for enhancing accuracy by reducing a large error in the estimated distance. The field experimental results performed in the POSCO steel company demonstrate that the developed system is capable of finding target positions with significantly improved accuracy and effectiveness.
location sensing active rfid worker safety management