Advanced traveler information system for metropolitan expressways in Shanghai, China

Many metropolitan cities experience severe congestion on their expressways. Advanced traveler information systems (ATISs) have been proposed as possible solutions for reducing congestion. A novel type of ATIS is presented; it is designed for network control of expressways and consists of three new kinds of variable message signs (VMSs). These VMSs are network-level guidance signs, road section signs, and entrance condition signs. Network-level guidance signs and road section signs provide traffic information in a graphical form, and entrance condition signs provide information about on-ramp conditions in a textual style. The ATIS composition and the functions of different VMSs are first presented. Then the information provision method for VMSs is addressed, followed by site placement of VMSs. ATIS evaluation results are presented and, finally, recommendations for future research are described.