Key Problems Research On The National Standardization Of Variable Message Signs

With the improvement of the function of variable message signs (VMS) and the development of urban traffic management based on VMS, VMS has been an important part of ITS. Now, more and more cities are benefit from using VMS, such as Beijing, Shanghai, Guangzhou and Shenyang. The specifications for guiding the VMS at design, setting and maintenance are continuously improved. Standardization of VMS is demand of improving ITS ability and buiding efficient, harmonious traffic system. Therefore, it is very important to establish a national standard for VMS.This paper made a study of several key issues on customizing national standardization of VMS in China. At first, the paper analyzed some of the major contents and specification about the VMS according to current national standards. Then, the paper revised the structure and improved the content of the text of VMS national standard. At the sometime, proposed and studied several key issues on design VMS, including classification, design of screen surface elements, location setting, etc. of VMS. At last, it analyzed a case to explain rationality and applicability of standardization of VMS.Specifically, the paper made a main study on the methods of designing screen elements and locations of VMS. The main elements of designing screen are topology of road network figures in screen, characters, dimension of screen, luminance and display cycle. Proposed some design procedure and typical examples. Proposed some advises and values of preposition in setting the VMS about site location and preposition. Based on the driver’s response of information, established a preposition model of VMS. Found three sites to explain the rationality of screen design, location sites and setting principle of VMS.The results of this study provided some theoretical and technical materials and proposed some references to improve the normalization and standardization of VMS.