Underground Localization System using a Combination of RFID and IMU Technologies

Underground mines are GPS-denied and extremely challenging environments, both from an environmental hazard as well as from a wireless communications standpoint. Inertial measurement unit (IMU) measurements used in dead reckoning algorithms quickly accrue heading drift errors and are unsuitable for large scale environments. By dividing up the underground environment into zones demarcated by Radio frequency identification (RFID) tags, the drift errors of the IMU dead reckoning are bounded. We present here a GPS-free localization system for miners making use of a hybrid approach based on RFID and IMU technologies. Successful localizing with the prototype system in Colorado School of Mines' Edgar experimental mine is achieved.