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This paper explores the potential safety performance of “Future Generation” automated speed control crash avoidance systems for Commercial Vehicles. The technologies discussed in this paper include Adaptive Cruise Control (ACC), second and third generation Forward Collision Avoidance and Mitigation Systems (F-CAM) comprised of Forward Collision Warning (FCW) with Collision Mitigation Braking (CMB) technology as applied to heavy trucks, including single unit and tractor semitrailers. The research [1[ discussed in this paper is from a study conducted by UMTRI which estimated the safety benefits of current and future F-CAM systems and the comparative efficacy of adaptive cruise control. The future generation systems which are the focus of this paper were evaluated at two separate levels of product refinement, “second generation” and “third generation” systems.

This paper examines how commercial vehicle aerodynamic improvements can be influenced by regulation particularly with respect to size and weight policy. It discusses the potential use of performance based standards (PBS) first introduced to optimize vehicle configurations in terms of vehicle stability and control and compatibility with highway geometry. There are several vehicle treatments that can be used to reduce aerodynamic drag, some of which lengthen or widen the vehicle without increasing cargo capacity. One such solution is referred to as ‘boat tails” consisting of a light weight external extension of the trailer allowing the air flow to remain attached as the vehicle cross section diminishes resulting in a reduction in the area of negative pressure at the end of the vehicle which reduces drag force.

This paper focuses on the safety performance of Commercial Vehicle Forward Collision Avoidance and Mitigation Systems (F-CAM) that include Forward Collision Warning (FCW) with Collision Mitigation Braking (CMB) technology as applied to heavy trucks, including single unit and tractor semitrailers. The study estimated the safety benefits of a commercially available F-CAM system considered to be representative of products currently in service. The functional characteristics were evaluated and its performance generically modeled to estimate safety benefits. This was accomplished through the following steps: (1) first characterize the actual performance of these systems in various pre-crash scenarios under controlled test track conditions, and then reverse engineering the algorithms that control warnings and automatic braking actions; (2) developing a comprehensive set of simulated crash events representative of actual truck striking rear-end crashes.