Abstract
This paper presents work conducted as part of an evaluation of the Ticketing Aggressive Cars and Trucks (TACT) III program of the North Carolina Highway Patrol. The goal of the TACT program is to reduce the contribution of aggressive driving behaviors to crashes involving commercial motor vehicles. In the present study, camera-based detection methods were used to identify the incidence of following too closely within the context of prevailing commercial motor vehicle and passenger vehicle volumes, speeds, and lane position both before and during TACT program enforcement operations. The data suggest that enforcement under the TACT program may have differential effects on the following distances of cars and trucks. An increase in the following distances of commercial motor vehicles was observed in the rightmost lane of an Interstate facility. A slight decrease in the speeds of commercial motor vehicles was also observed during the enforcement period, but no significant changes in speeds or vehicle following times were observed for passenger vehicles. The results indicate that the methodology developed is sensitive and is able to detect changes in driver behavior. It may thus become a potential alternative strategy for evaluation of the TACT program. The use of roadside instrumentation further enables future applications for automated driver feedback, in which following too closely and speed violations may be detected automatically and the information relayed to the driver in an infrastructure-to-vehicle context like that for dynamic speed signs. Automated methods developed as part of this research could also be used for automated enforcement in future applications.