Evaluation of advanced emergency braking systems in drowsy driving-related real-world truck collisions.

Study objectives: The effectiveness of advanced emergency braking systems (AEBS) in preventing drowsy driving-related truck collisions remains unclear. We aimed to evaluate the damage-mitigation effect of AEBS on drowsy driving-related collisions involving large trucks using collision rate and damage amount.

Methods: Data collected by a Japanese transportation company from 1699 collisions involving 31 107 large trucks over 7 years were analyzed post hoc. The collision rate (number of trucks with collisions/total number of trucks) and damage amount (total amount of property damage and personal injury) were compared based on whether the collisions were caused by drowsy or nondrowsy driving and whether the trucks were equipped with AEBS or not.

Results: For all and nondrowsy driving-related collisions, the collision rate for the 12 887 trucks with AEBS (1.62 and 1.20 collisions/truck/7 years, respectively) was significantly lower than that for the 18 220 trucks without AEBS (1.94 and 1.56 collisions/truck/7 years, respectively; p = .04 and p = .008, respectively). However, for drowsy driving-related collisions, the collision rate did not significantly differ between trucks with and without AEBS. The damage amount in neither type of collision (drowsy vs. nondrowsy) significantly differed between trucks with and without AEBS.

Conclusions: Regarding the collision rate of large trucks, AEBS was effective in nondrowsy driving-related collisions, but not in collisions involving drowsy driving. The damage amount was not mitigated for trucks with and without AEBS regardless of the collision type. The limited effect of AEBS for damage mitigation suggests the need for combined use with other safety-support systems that intervene in driving operations.