# Motion Control System of Unmanned Railars Based on Image Recognition  
[PERSON]  
Department of Electrical Engineering, I-Shou University, Kaohsiung City 84001, Taiwan; [EMAIL_ADDRESS] (Y.-W.T. ); [EMAIL_ADDRESS] (T.-W.H. ); [EMAIL_ADDRESS] (C.-L.P.)  
[PERSON]  
Department of Electrical Engineering, I-Shou University, Kaohsiung City 84001, Taiwan; [EMAIL_ADDRESS] (Y.-W.T. ); [EMAIL_ADDRESS] (T.-W.H. ); [EMAIL_ADDRESS] (C.-L.P.)  
[PERSON]
In the early days of railways, when train speed was not fast, locomotive engineers operated trains by watching signal lights and signs on the tracksides, and then manually made proper decisions to control the motions of trains without colliding with other trains. Later on, when train speeds were too fast for locomotive engineers to correctly recognize trackside signals and operate trains safely, Track Circuit Based Train Control systems (TBTC) [1] were developed to ensure the safety of railway operations. A track circuit is a simple electrical device used to detect the absence of a train on rail tracks, and thus to inform signalers and control relevant signals as shown in [2]. Nowadays, with the popularity of high-speed railways and the demand of increasing capacity for more rapid travel with more passengers, the maintenance time left for track circuits becomes less and less. To overcome this situation, the more advanced Communication Based Train Control (CBTC) system [1; 3; 4; 5], whose system overview as shown in [6] was introduced and became the modern railway signaling system for mass rapid transit systems worldwide. A CBTC system is a \"continuous, automatic train control system utilizing high-resolution train location determination, independent from track circuits; continuous, high-capacity, bidirectional train-to-trackside data communications; and train-borne and wayside processors capable of implementing Automatic Train Protection (ATP) functions, as well as optional Automatic Train Operation (ATO) [5] and Automatic Train Supervision (ATS) functions\", as defined in the IEEE 1474 standard [7]. Currently, CBTC systems apply radio devices to provide continuous and high-speed data communications such as monitoring train speeds and track conditions between train and tracksides. Since the CBTC systems can measure train speeds, the optimal design of CBTC ATO speed profiles that minimizes the energy consumption for a target running time, were studied [8; 9]. From our above brief introduction, we know that both the TBTC system and CBTC system have complex hardware architectures. There are many detecting devices distributed along the tracksides. Therefore, both implementation cost and maintenance cost are very high. Furthermore, equipment malfunction, weak signal strength, saturation of the communications medium or electromagnetic interference can result in failure of the train control system, thus affecting normal train service. Detecting and fixing the failure could be a time consuming and costly task. For these reasons, an auxiliary control system of CBTC system is desirable. Unlike the trains in railway systems that transport both passengers and cargos on different spurs, railcars usually have their own dedicated function and travel on a fixed path. Therefore, railcars usually have less safety concern and are more suitable for unmanned operations. For simple applications, TBTC as well as CBTC is too complex and too costly for controlling the motions of railcars. According to briefly reviewing the history of signaling systems of train control, we find that one thing in common in the evolution of train signaling systems. That is the data communications between train and trackside devices. Inspired by this idea, and considering that many railcars actually operate in fixed luminous environments, we developed a motion control system of unmanned railcars based on image recognition in this research. Although train drivers cannot correctly recognize signs and signals along the tracksides in high-speed railways, computer vision can.