Effects of ABS Controller Parameters on Heavy Truck Model Braking Performance 2006-01-3482

This paper covers research conducted at the National Highway Traffic Safety Administration's Vehicle Research and Test Center (VRTC) examining the performance of semitrailer anti-lock braking systems (ABS). For this study, a vehicle dynamics model was constructed for the combination of a 4×2 tractor and a 48-foot trailer, using TruckSim. ABS models for the tractor and trailer, as well as brake dynamics and surface friction models, were created in Simulink so that the effect of varying ABS controller parameters and configurations on semitrailer braking performance could be studied under extreme braking maneuvers. The longitudinal and lateral performances of this tractor-trailer model were examined for a variety of different trailer ABS controller models, including the 2s1m, 4s2m, and 4s4m configurations. Also, alternative controllers of the same configuration were studied by varying the parameters of the 2s1m controller. Compared to a semitrailer equipped with a 2s1m system, it was discovered that although it provides little benefit for straight-ahead braking maneuvers, upgrading to a more complex ABS system (4s2m or 4s4m) could aid in lateral stability. It was also shown that changing the ABS controller parameters within the same configuration, such as thresholds and holding durations, could greatly affect the braking performance of the tractor-trailer.