US Patent 9434397 Positive train control system and apparatus therefor

A positive train control may comprise a plurality of different sensors coupled to a processor that determines whether there is an object on a track way and/or an anomaly of a track way, and if there is, provides an alert and/or a train control action. The plural sensors may include a visual imager, an infrared imager, a radar, a doppler radar, a laser sensor, a laser ranging device, an acoustic sensor, and/or an acoustic ranging device. Data from the plural sensors is geo-tagged and time tagged. Some embodiments of the train control employ track monitors, switch monitors and/or wayside monitors, and some employ locating devices such as GPS and inertial devices.