A control scheme of vehicular strings

This paper deals with the two hierarchical control methods on a single guideway in the public transportation system; the upper controls the vehicular strings and the lower controls the individual vehicles. In the vehicular strings control system, the mathematical model is built as a discrete linear-state regulator problem where the delay time is chosen as state variable and the deviation from the scheduled driving time between adjacent stations is chosen as control variable. The performance index is defined as a quadratic form concerning the delay time, the deviation from the time interval and that from the driving time. We can realize any vehicular string control system with various objectives by selecting the relative importance of the weighting coefficients of the first and the second terms in the performance index. Next, the controller of the individual vehicle is called AVO (automated vehicular operation) and its two main functions are to drive a vehicle between stations in the time commanded by the vehicular string controller and to keep an accurate stoppage position at a station. The problem of controlling vehicles is modelled as a discrete linear-state regulator problem, where the deviations from both scheduled time and velocity are chosen as state variables and that from any scheduled driving force is as control variable. The performance index is defined as a quadratic form concerning the state variables and control variable.