Method and apparatus for controlling trains by determining a direction taken by a train through a railroad switch

摘要

An apparatus for determining the presence of a third rail disposed between parallel railroad tracks as a train progresses along said parallel railroad tracks and further for determining the relative direction of motion of said third rail with respect to said first two rails and further for determining the rate at which the third rail moves with respect to the first rails is disclosed, which is a low power radar sensor disposed underneath the rail vehicle and directed toward the rail on the opposing side of the vehicle. In a preferred embodiment, two rail detectors are shown which are disposed on opposite sides of the rail vehicle. The radar detectors are coupled with an onboard computing device and with other components of an advanced train control system which can be used for precisely locating the train on closely spaced parallel tracks and further for updating and augmenting position information used by the advanced train control system. The system including GPS receivers and wheel tachometers for providing alternate sources of information for position determination.