Between June 2000 and September 2008 the University of North Florida, Institute of Police Technology and Management (UNF, IPTM) performed over 200 deceleration tests on over 70 commercial vehicles in a variety of configurations including various vehicle types, load conditions, and tests with and without the ABS system activated. The vehicle types tested were tractor w/van type trailer, tractor only (bobtail), straight box/service trucks, dump trucks, fire trucks, concrete mixing trucks, double trailers, articulated tankers, school and metro buses and articulated flatbeds.
Vehicles were instrumented to record selected system performance parameters such as brake canister pressure rise, vehicle speed, position at brake pedal application, vehicle acceleration, etc.
This paper reviews and summarizes the stopping distance data from these tests and provides insight into commercial vehicle stopping distance, drag factor for all of the tested vehicles and configurations. It will also look at how vehicle type, load condition, and ABS affect stopping distances. This information will be of value to accident investigators, regulators, and vehicle designers, as it will provide significant data regarding the braking performance of these vehicles.