icccbe 2010 Nottingham University Press Proceedings of the International Conference on Computing in Civil and Building Engineering W Tizani (Editor) System development and performance evaluation of track intrusion in Taipei MRT system Lee-kuo Lin, Chih-chian Chang & Po-yen Wu National Taipei University of Technology, Civil Engineering Department Abstract Taipei has serviced metro rapid transportation (MRT) system since March 1996. It is an indispensable transportation and becomes the solution of the traffic jam in Taipei city. Up to today, the daily transportation is about 1.23 million passengers in average. However, many incidents are still happened from time to time during the operation period, such as personnel intrusion occasionally falling into the railway area, and etc.. These incidents always cause MRT system delay and even damage losses of lives and properties. Therefore the Taipei Rapid Transit Corporation (TRTC) tries to develop several prevention systems including a track intrusion detection system and installing automatic platform gates to effectively prevent personnel intrude the railway area. Because these two systems need to combine several techniques, such as computer software, wireless transmitting technology, hardware and so on. Therefore this article will introduce the system algorithm and operating structure of these track intrusion detection system and automatic platform gates system. Then the prevention performance based on cost analysis will also be discussed. By calculated and compared the construction cost of these two systems, the average construction cost for each track intrusion detection system is about 2.35 million TW dollars (44,508 GBP) and the average construction cost for automatic platform gates of each station is about 54 million TW dollars (1.023 million GBP). Keywords:MRT,prevention system, track intrusion, automatic platform gates, prevention performance. 1 Preface 1.1 Introduction Metropolitan area in recent years in the domestic population growth and economic growth, transportation issue has always been one of the main policy objectives. Development of new transport system is an important objective; TRTC since opening in March 1996 has became the Taipei metropolitan area to alleviate traffic congestion. The Taipei MRT system includes eight operating routes (Figure1). The accumulated record of passenger transportation is more than 3.5 billion in 2009, the average record is 1.23 million passengers per day (Chen et al., 2009). Furthermore, in order to meet the New Year's activities in Taipei 6:00 pm December 31, 2008 and 6:00 pm in January 1, 2009, a total of nearly 1.95 million passengers, compared with the 2008 New Year period, transport 1.937 million passengers (Table 1). Such situation will increase the potential danger, especially when platforms of MRT full with passengers (Figure 2).
Meanwhile, there are many incidents happened in TRTC from time to time during the operation period, such as personnel intrusion occasionally falling into the railway area, and etc.. Therefore the TRTC tries to develop a track intrusion detection system in 2006 and install automatic platform gates (APG) at three stations on December 1, 2006 to effectively prevent personnel intrude the railway area (Hsu, 2008). Figure 1. Future road map of Taipei MRT. (TRTC, 2009; Yu, 2007) Figure 2. Passengers at platform on 2009 New Year s Eve at Taipei MRT
Table 1. Accumulated passenger record of New Year s Eve in Taipei MRT. (TRTC, 2009) Year Accumulated passengers(million/day) 2001 1.21 2002 1.30 2003 1.375 2004 1.43 2005 1.565 2006 1.576 2007 1.604 2008 1.9298 2009 1.9508 1.2 Research background Taipei MRT system is opened form March 1996. Up to today, due to a number of staffs invasive, the TRTC launched a project called "track intrusion detection system" in early 2005. Through analyzed and tested, this system is arranged at practice to detect and work as early warning equipment. The system has been completed in January 2006. There are three stations Dan-Shui station, Jiang-Zicui station and Guan-Du station, starting to test the system performance. The automatic platform gates (APG) were launched in early 2006 and started worked on December 1 2006. There are three stations, Taipei station-dan-shui line, Taipei station-nan-gang line and Zhongxiao-Fixing station, accumulated six sides of automatic platform gates are starting to work for the prevention purpose. This study based on literatures review and cost analysis theory, as well as the collection data of the Taipei MRT system from 1996 to 2009, including install and maintenance cost of these two system. In principle, this paper is currently related to the outcome with the installation of security protection system. 2 System Development of Track Intrusion Detection By searching to effectively deal with invasive and immediate follow-up and minimize the impact. The track intrusion detection system works on analysis and planning at appropriate locations detector and alarm devices, hoping to quickly find invasive track, and immediately notify the station staff. Then informs the driver to stop the train, and takes appropriate reaction to reduce accident. The system functions are shown in Figure 3 and Figure 4, in accordance with the description as follows (Hsu, 2008): Figure 3. Functional structure of the track intrusion detection system. (Hsu, 2008)
Figure 4. System structure of track intrusion detection system. 2.1 Detection subsystem In accordance with the characteristics of the station, advise passenger who should not exceed the warning level to avoid danger. Therefore, the detection system will cover platforms track detection area, the track-side wall of the door to detect areas, the platform-side space, as well as the platform to detect the yellow line detection zone, for a total of four kinds of detection region (Figure 4). (1) Platform track detection zone: In front of the platform area can detect a high degree of more than 88cm tall child, which is greater than 22cm in length and diameter of the ball. (2) Doors on both sides of the detection zone: On both sides of the platform, passengers can be detected from the next orbit. (3) Platform gap detection zone: the region to detect about 1 meter to detect trains and doors on both sides of central gap. (4) Detection platform cordon area: From the platform of the cordon, height of 180cm range, can detect the diameter of the ball longer than 31cm. In order to cope with all these four types of detection regions. This system establishes platform sidewall door detectors between both sides of the platform and platform security line. 2.2 Warning device subsystems Equipment is to provide the warning message to the station staff and train drivers, to facilitate understanding of track conditions. (1) Alarm signals plate: The display system detects the status of the district. Normal situation shows green light. The emergency shutdown mode function is shown as red light. The light changes from green to red when the alarm activates. The station staff will help to treat the situation during emergency. (2) Pre-recorded voice broadcast: There are additional expansions of a radio and a voice adapter. Voice adapter can store different broadcasting voice. The user can choose the type of alarm needed depending on the situation. Every platform has two systems installed. (3) Projective lights: Each month projection lights will be reinstalled. The projection lights will be activated when the alarm triggers. (4) Early warning lights: Installation location in each direction of the platform to the station with two early-warning lights what will, brighten 150m far away from the identify. Lights usually show with green light. When system alarm, it will show a red light to remind the train drivers.
(5) Rapid camera: Two fast cameras are installed. When the alarm activates, the system can automatically turn to the camera location. It will immediately notify the station staffs in order to carry out an emergency procedure. 2.3 Station processing subsystem One server and one programmable controller can provide all the system's computing functions, and can be dealt with immediately according to the detector s information and its response. The system alerts the following types and movements: (1) Invasive orbit warning: The system tracks events on the invasive platform. The system will sound the alarm and voice broadcast will start while lighting and warning lights turned on. Tunnel lights will be on automatic mode at the same time. The train can activate an emergency brake to stop the train. (2) Penetrated the wall-side door alarm: When the wall-side door opens, the system will issue alerts and notify the station for voice broadcasting. Projection lighting and early warning lights will go on as well as the digital video equipment and tunnel lighting. The train will stop if necessary. (3) Invasive trains and side walls central alarm: If the platform side of the central detection zone is being activated, warning signs will be displayed at the station. Furthermore, it will sound the alarm and start the pre-recorded voice broadcast, while the digital video equipment starts recording. (4) Exceeding the warning limit: The train will stop if the level of warning exceeds the limit. System will sound the alarm and notifies the Inter-Agency Consultation. Voice broadcast will start to warning passengers. 3 Introduction of automatic platform gates 3.1 System development In general, there are kinds of platform gates in Taipei MRT, including platform screen door (PSD) and automatic platform gate (APG). PSD was installed in Mu-zha line at the beginning of system construction. APG (Figure 5) was selected to install in Taipei station-dan-shui line, Taipei station- Nan-Gang line and Zhongxiao-Fixing station on December 1, 2006 due to these three stations are full with passengers most at the time. The system operating procedure of APG or PSD is shown at Figure 6. Figure 5. Automatic platform gates of Taipei MRT.
WIRELESS Wireless interface INTERFACE on car Remote TRAIN control DOOR of car s CONTROL door RELAYS ATO Automatic Driver DRIVER cabin CABIN Adaptor Tx/Rx Wireless interface of stations Signal equipment room Traffic SIGNALLING sign s interface INTERFACE CIRCUITS Electronic EXISTING signal SIGNALLING of traffic sign CIRCUITS Operation control OCC/ center (OCC) PAO PSD Controller PSD Back ending wall TAILWALL Figure 6. Frame structure and system operation of the PSD. Front ending wall HEADWAL 3.2 Operation control centre Once the system of track intrusion or automatic platform gates detects special signal, the system will automatic transmit a message to the operation control centre (OCC) of Taipei MRT for special treatment (Lin et al., 2008). The OCC is the hub of the Taipei MRT. Its major tasks are the control and monitor operations at all levels, including the dispatching of train, maintenance scheduling and the coordination and management of emergency situations (TRTC, 2007). 4 Analysis of construction and maintenance cost 4.1 Track intrusion detection system By calculated and compared the construction cost of the track intrusion detection system project at Dan-Shui station, Jiang-Zicui Station and Guan-Du station; the average construction cost for each station is about 2.35 million TW dollars (44,508 GBP). Such data does not contain cost of project design and program software. For deriving the annual maintenance cost of the track intrusion detection system, this study collects real data of maintenance cost in Taipei MRT from January 2006 to November 2009. Such data includes routine maintenance spending of material and labor. After calculated, the annual maintenance cost of each station is about 215,098 TW dollars (4,084 GBP). 4.2 Automatic platform gates By calculated and compared the construction cost of the automatic platform gates system project at Taipei station-dan-shui line, Taipei station-nan-gang line and Zhongxiao-Fixing station; the average construction cost for each station is about 54 million TW dollars (1.023 million GBP). Such data does not contain cost of project design and program software. For deriving the annual maintenance cost of the automatic platform gates system, this study collects real data of maintenance cost in Taipei MRT from December 2006 to November 2009. Such
data includes routine maintenance spending of material and labor. After calculated, the annual maintenance cost of each station is about 750,000 TW dollars (14,205 GBP). 5 Conclusion This article introduces two different types of safety prevention system in Taipei MRT, the first one is the track intrusion detection system and the second one is automatic platform gates. Both track intrusion detection system and automatic platform gates system need to develop hardware equipments and integrate with computer software to ensure the performance purpose. Meanwhile, this article also derives construction and maintenance cost of these two systems for related reference. Up to today, both systems are still working well at practice in Taipei MRT. Meanwhile, after a value analysis research focusing in Taipei MRT with track intrusion detection system, the conclusion is that the system is valuable (Hsu, 2008). References CHEN, RICHARD CEN-LAUN, CHEN, CHIN-TE and YEN, HSIN-HUNG, Benefit Analysis and Future Perspectives of Energy Conservation and Carbon Dioxide Emission Reduction-Taipei Rapid Transit Corporation, Railway Operation & Management, July 2009, 6-22. HSU, SEN-HAO, 2008, The Value Analysis on Automatic Platform Gates and Track Intrusion Detection System of MRT system, M.S. thesis, National Taipei University of technology, Taipei, Taiwan. LIN, LEE-KUO, JIAN CHEN-YOU and CHANG, CHIA-FENG, 2008, A Maintenance Management System of Transportation Auxiliary Facilities, The Conference of ICCCBE-XII & INCITE 2008, Beijing, China, 107-1-107-6. TRTC, 2009, Transportation Record,, Available online: http://www.trtc.com.tw/c/, Last accessed: December 2009. TRTC, 2007, TRTC Service plans, Taipei, Taiwan. YU, YU-MING, 2007, The investigation on the Management of Safety and Health at Metropolitan Rapid Transit System, M.S. thesis, National Taipei University of technology, Taipei, Taiwan.