REAR-END COLLISION-WARNING ALGORITHMS WITH HEADWAY WARNING AND LEAD VEHICLE DECELERATION INFORMATION

This paper presents the results of an analytical study of rear-end collision-avoidance warning systems using the Rear-End Accident Model and Countermeasure Simulation (REAMACS) Program. The purpose of the exercise was to estimate the effectiveness of warning algorithms that (1) utilize information about lead vehicle deceleration in their calculations and (2) warn drivers when the headway to a lead vehicle falls below some minimum. REAMACS generates rear-end collision situations in freeway traffic and models the effects of collision warning systems on rear-end crash rates. The model uses actual freeway traffic data and empirically-based analytical distributions for driver reaction time and lead car braking levels to generate the initial conditions that determine whether or not a crash occurs. Previously reported applications of the model indicate that collision warning has the potential to reduce the number of serious rear-end crashes in freeway traffic by as much as 60 percent. In the current application, REAMACS is used to estimate the relative benefits of (1) an algorithm based on closing rate and no minimum headway, (2) a closing rate algorithm with a 0.5 second headway warning, and (3) a closing rate algorithm with a 1.0 second headway warning. The analysis also compares the relative effectiveness of warning algorithms with and without knowledge of lead vehicle deceleration. The results suggest a significant advantage for warning algorithms using knowledge of lead vehicle deceleration, especially in more severe crashes. The addition of headway warnings also improves effectiveness, but primarily in lower speed crashes. Driver compliance with headway warnings is an issue.

• Supplemental Notes:
  • Five volumes of papers and one volume of abstracts comprise the published set of conference materials.
• Corporate Authors:

  VERTIS

  TORANOMOM 34 MORI BUILDING 1-25-5
  TORANOMON, MINATOKU, TOKYO 105  Japan 
• Authors:
  • Farber, E
  • Huang, M
• Conference:
  • Steps Forward. Intelligent Transport Systems World Congress
  • Location: Yokohama, Japan
  • Date: 1995-11-9 to 1995-11-11
• Publication Date: 1995-11

Language

• English

Media Info

• Pagination: p. 1128

Subject/Index Terms

• TRT Terms: Algorithms; Crash avoidance systems; Deceleration; Headways; Intelligent transportation systems; Mathematical models; Motor vehicles; Rear end crashes; Speed; Traffic speed; Warning systems
• Uncontrolled Terms: Models
• Geographic Terms: United States
• Subject Areas: Highways; Operations and Traffic Management; Vehicles and Equipment; I91: Vehicle Design and Safety;

Filing Info

• Accession Number: 00722049
• Record Type: Publication
• Report/Paper Numbers: Volume 3
• Files: TRIS
• Created Date: Jun 25 1996 12:00AM