Time Synchronization and Positioning Accuracy in Cooperative IntelliDrive℠ Systems

The effect of internal random processing delays and absolute time synchronism errors in cooperative positioning applications is discussed. The need for and general nature of new requirements for time accuracy and synchronism are described. A variety of cooperative vehicle-to-vehicle applications have been proposed to provide improved situational awareness to vehicles in order to improve safety and avoid collisions. Many of these applications have assumed positioning requirements on the basis of the geometric features of the application under consideration. Recent work in the IntelliDrive Proof Of Concept project carried out in Michigan indicates that the positioning requirements necessary for successful cooperative application may be substantially more involved than simply specifying a global positioning systems (GPS) accuracy consistent with the EdMap objectives. Specifically, the relative motion between cooperative elements in the IntelliDrive system (e.g. between a vehicle and a roadway feature (e.g. lane marking, limit line, curve, etc., or between multiple vehicles) means that the accuracy of a situational assessment, specifically, the positions, speeds and trajectories of the relevant “threats”, depends on absolute time accuracy and internal process delays as well as absolute positioning capability. This paper examines the implications of time, process delays and position accuracy in the context of these cooperative, but physically unconnected elements of the IntelliDrive System with the objective of identifying how to best meet the overall positioning needs of cooperative systems.

• Corporate Authors:

  ITS America

  1100 17th Street, NW, 12th Floor
  Washington, DC  United States  20036
• Authors:
  • Andrews, Scott
• Conference:
  • ITS America 20th Annual Meeting & Exposition
  • Location: Houston TX, United States
  • Date: 2010-5-3 to 2010-5-5
• Publication Date: 2010

Language

• English

Media Info

• Media Type: CD-ROM
• Features: Figures;
• Pagination: 7p
• Monograph Title: ITS America 20th Annual Meeting & Exposition

Subject/Index Terms

• TRT Terms: Awareness; Cooperation; Global Positioning System; Traffic delays; Traffic flow; Traffic safety; Traffic signal control systems; Vehicle design; Vehicle to vehicle communications
• Identifier Terms: IntelliDrive (Program)
• Uncontrolled Terms: Crash avoidance
• Geographic Terms: Michigan
• Subject Areas: Data and Information Technology; Highways; Safety and Human Factors; Vehicles and Equipment; I91: Vehicle Design and Safety;

Filing Info

• Accession Number: 01342829
• Record Type: Publication
• Files: TRIS
• Created Date: Jun 23 2011 9:07AM