Mining Contract: Feasibility Study: Vision-Aided Personal Inertial Tracking System for Mining

Contract Status & Impact

This contract is complete. To receive a copy of the final report, send a request to mining@cdc.gov.

This work tested how well emerging personnel localization technologies performed when localizing underground miners. The contractor conducted three tests of a personnel localization system at the Safety Research Coal Mine (SRCM) in Pittsburgh, PA. The tests focused on localizing miners while walking, but the contractor also performed tests on localizing miners while crawling and riding on a vehicle.

The localization system tested was originally developed under support from the Defense Advanced Research Projects Agency (DARPA) to localize soldiers. It uses two inertial measurement units (IMUs) currently valued at approximately $8,000 each, and it does not attempt to address size, power, and safety requirements specific to the mining environment. Therefore, it is not practical for mining applications due to cost, size, weight, power, and safety.

Reusing the existing soldier localization system allowed the contractor to evaluate localization technologies rapidly in ways that would otherwise have been impossible. The soldier localization system is self-contained, and the tests used very inexpensive, passively powered RFID tags and visual markers to augment the system. For the tests, the tags and markers were placed near presurveyed spads in the SRCM. They functioned as radio and visual landmarks similar to a fixed constellation of GPS satellites.

Without RFID or visual fixes, position error in the localization system is approximately 2 parts in 100 over distances of several thousand feet; performance degrades over time. In the tests using RFID tags, the average system error over all spad spacings was 5 ft for walking distances ranging from 25 ft to approximately 3,000 ft. In the SRCM, spads were spaced at varying distances between a 25 ft and 100 ft. These results apply while walking.

The contractor conducted a brief analysis of the system’s commercial potential and concluded that a product based on these technologies needed to gain a significant market share to be worth commercial investment. If the same solution could be sold to first responder, law enforcement, military or even consumer customers, the associated higher volumes would make these technologies more attractive for commercialization.