Article Preview
TopIntroduction
Intelligent Transportation Systems (ITS) are designed to solve problems such as traffic accidents, congestion, and environmental impact by applying advanced information, communications, electronics, mechanics, and control technologies to transportation management and traffic systems (Chang & Chen, 2001; Sussman, 2005). The rapid development of information and communications technologies has made it possible to apply advanced techniques to solve traditional traffic problems. The recent development of ITS in advanced countries not only enhances service quality for most road users, such as vehicle drivers, but also improves transportation problems for road vulnerable individuals, such as pedestrians. Using ITS technologies to guarantee the safety of pedestrians at intersections has become an important issue because intersections are the places where pedestrians can easily conflict with vehicles (Fontaine & Gourlet, 1997; Najm, Smith, & Smith, 2001; Sarkar, Van Houten, & Moffatt, 1999). To improve pedestrian crossing safety at intersections, traffic engineers usually design pedestrian phases in signal timing plans. However, some intersections in rural areas cannot be signalized due to installation costs and vehicle delay issues. Therefore, protecting pedestrians who are crossing the roads from accidents at unsignalized intersections is a major concern for traffic engineers and government authorities trying to improve road safety. One way to provide the crossing pedestrians with the higher right of way at unsignalized intersections is to enact traffic regulations that force drivers to stop to allow pedestrians to cross the road. Regulatory signs can also be installed ahead of an unsignalized intersection to remind drivers to yield to crossing pedestrians. Examples of these signs in the Manual on Uniform Traffic Control Devices (MUTCD) (2003) include “Yield Here To Pedestrians” signs (R1-5, R1-5a) and “In-Street Pedestrian Crossing” signs (R1-6, R1-6a). Another way to grant pedestrians the right of way is to develop an intersection pedestrian collision warning system (IPCWS). An IPCWS is a pedestrian protection system that integrates advanced detection technologies, warning devices, and collision warning systems to provide timely alert messages to drivers and pedestrians for collision avoidance at intersections. This system can be used to prevent vehicles from colliding not only with pedestrians legally crossing the road at unsignalized intersections, but also pedestrians illegally crossing the road at signalized intersections.