A Side Collision Warning System for Transit Buses

Side collisions make up the highest percentage of transit collisions, accounting for almost 40% of all accidents. Therefore, transit operators have placed preventing this type of accident as the issue that they would most like to see investigated as part of the transit IVI program. Unfortunately, there have been few, if any, studies about the use of collision warning systems in transit. In part, this is due to the difficulty of developing systems, which will operate in city driving conditions (low speeds and high vehicle/pedestrian densities).

Researchers will take on these tasks as part of this research:

  • Analyze available crash data.
  • Establish functional goals.
  • Assess existing systems.
  • Develop preliminary performance   specifications.
  • Investigate state of the art of technology.
  • Select test system.
  • Construct/acquire collision avoidance system.
  • Conduct testing to validate performance specs.
  • Finalize performance specs.

Principal Investigator(s):

Sue McNeil


Sue McNeil
Charles Thorpe
Christoph Mertz
David Duggins
Teruko Yata
Liang Zhao




To develop a warning system which helps a driver of a transit bus to avoid side collisions with pedestrians, other vehicles, or stationary objects.


Side-looking sensors developed for heavy trucks and light vehicles have been applied to buses in demonstration projects. Three primary concerns exist with these systems. First, they are tuned to look for vehicles and other large objects, and they miss smaller objects such as children. Second, they are designed to cover a full lane width, so they generate nuisance alarms in the tight quarters of bus operations. Third, in order to cover the entire 40-foot length of a bus, existing systems require up to 10 sensors per side, raising concerns about installation and maintenance costs.

Expected Results or Products:

Performance specifications of side collision warning systems for buses.


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P.S. Sriraj
Urban Transportation Center
University of Illinois at Chicago
412 South Peoria Street, Suite 340
Chicago, IL 60607
Voice: (312) 413-7568
Fax: (312) 413-0006
Email: sriraj@uic.edu


Carnegie Mellon University with funding from the Federal Transit Administration
Pennsylvania Department of Transportation

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