Too Close for Comfort: Evaluating a Reward-based Approach to Increase Drivers’ Headway

Tailgating is often implicated as a leading contributor to rear-end collisions but this behaviour is difficult to remediate because drivers are poor at estimating their own headway. Our first goal was to compare novice and fully licensed drivers as they applied existing headway interventions in a driving simulator. Our second goal was to develop an automated, reward-based approach to encourage longer headways. We first compared headway in the driving simulator to previous studies on real-world car following behaviour by asking drivers to (i) achieve what they perceived to be the minimum safe headway or to (ii) employ the common “2 second rule” intervention. We observed a close agreement between the headways achieved in the simulator and those achieved in prior real-world car-following paradigms. We then implemented our headway evaluation system and compared headway across instruction type: (i) minimum safe headway, (ii) “2 second rule”, or (iii) the headway evaluation system. We observed that fully licensed motorists maintained the longest headways while using our system. While drivers reported that the headway evaluation system was easy and appealing to use, they did not foresee continuing to use the device in the future. The current system may be beneficial for driver training applications or to promote situation awareness during the use of automated driver assistance systems such as adaptive cruise control.