Decentralized control of heavy-haul trains with input constraints and communication delays

The heavy-haul trains consist of a large number of locomotives and wagons which usually cover a very long range of train tracks with different slopes and curvatures. As a consequence, the control design for the heavy-haul trains has posed a significant challenge due to the modeling complexity and the complicated traveling conditions, under which the problems of communication delays and input constraints naturally arise. In this paper, a novel decentralized control design is proposed for the heavy-haul trains by explicitly addressing the issues of input constraints and time-varying communication delays. Specifically, the complicated longitudinal dynamical model of the heavy-haul trains is first converted into a double integrator form by introducing a set of state and input transformations. Then, a decentralized cooperative control is proposed to regulate the speeds of individual train units (locomotives and wagons) to the desired profile with the objective of maintaining the minimum in-train force for safety consideration. It is rigorously proved that the closed-loop system is uniformly asymptotically cooperative stable under the least communication conditions among individual train units. Extensive simulations are conducted to validate the performance of the proposed new design.