Method and apparatus for controlling train positioners using motor energy to determine the mass of the train and the mass of the train to determine maximum deceleration

摘要

A method and apparatus for operating a train positioner for moving one or more railroad cars of a unit train are disclosed. The positioner is engaged with the train while the positioner is stopped at an initial location. The positioner is moved and the train is accelerated to a constant speed. The energy expended by the positioner in accelerating the train to the constant speed is determined and apparent mass of the train is calculated from this energy. From the apparent mass of the train, a maximum force to which the positioner should be subjected, and a deceleration rate, a deceleration point adequate to stop the train by a predetermined, final location is calculated. The positioner is decelerated beginning at the deceleration point and at the deceleration rate until the train is stopped by a final location. In a preferred embodiment, the deceleration rate is also calculated from the apparent mass of the train and the maximum force to which the positioner should be subjected.