A locomotive location system and method utilizes inertial measurement
inputs, including orthogonal acceleration inputs and turn rate
information, in combination with wheel-mounted tachometer information and
GPS/DGPS position fixes to provide processed outputs indicative of track
occupancy, position, direction of travel, velocity, etc. Various
navigation solutions are combined together to provide the desired
information outputs using an optimal estimator designed specifically for
rail applications and subjected to motion constraints reflecting the
physical motion limitations of a locomotive. The system utilizes
geo-reconciliation to minimize errors and solutions that identify track
occupancy when traveling through a turnout.