Precise Stop Control and Experimental Validation for Metro Train Overcoming Delays and Nonlinearities

Automatic Train Operator (ATO) is a system equipped on metro trains and controls train operation. One of the main functions of ATO is precise stop control, which aims to ensure that a train stops at a designated position on the platform with errors within a predefined specification. Precise stop control is an important function because trains stopping outside of the specification adversely affect passenger safety and punctuality of operation schedule. It is difficult to achieve high accuracy and precision for an ATO since trains are heavy, train control feedback loops involve several steps that cause various levels of time delay, and the actuation has nonlinear characteristics. Moreover, although existing studies propose algorithms to overcome some of the said challenges, few include experimental validations because access to the experimental environment is extremely limited. In this work, we address each one of the challenges and propose a mitigation algorithm, respectively. Moreover, unlike other studies, we experimental validate on an actual train the proposed algorithms. The precise stop control performance is shown to be superior to that of existing system.