Zone-based, underground localization system using passive reverse RFID and IMU technologies, A

Abstract

In order for miners to mitigate hazardous dust concentrations underground, they must first identify where in the mine the high concentrations occur. To do this, they wear dust monitoring units to track the amount of dust in the regions they travel and recording their locations by hand. This is extremely time consuming for large underground mines making an automated localization system a necessity. Underground localization systems typically use massive amounts of infrastructure such as active radio beacons or modulated light sources that require connection to power and communication infrastructures making them unfeasible for cost-effective and rapid deployment. This thesis describes a wearable system that uses a combination of IMU dead reckoning, reverse passive RFID trilateration, and map matching to localize a user in both an indoor and underground environment. The only infrastructure required for the system to operate are clusters of passive RFID tags sparsely placed throughout the area. IMU dead reckoning localizes the user in between tag clusters while the RFID tag clusters reset the drift errors accrued by the IMU. Map matching projects the dead reckoned values onto a path, sacrificing a user’s lateral distance from the path for a massive increase in accuracy. The system presented successfully localizes a user at Colorado School of Mine’s Edgar experimental mine.