This study examines to what extent the ability to attain a required headway of 1 or 2 s can be improved through practical driving instruction under real traffic conditions. It also investigates whether the learning is sustained after a period during which there has been no controlled training. Two methods of training were used: time based (in seconds) and distance based (in a combination of meters and car lengths). For each method, learning curves were examined for 18 participants at speeds of 50, 80, and 100 km/hr. The learning process was based on perceptual cues from the driving scene and feedback from the experimenter, regardless of the formal training method. The results indicated that drivers were weak in estimating headway prior to training using both methods. Both the time and distance training of headway appeared to improve drivers' ability to attain required headways. The learning process was rapid for both methods and similar for all speeds. After just one trial with feedback, there was already a significant improvement. The learning was retained over time, for at least the one month examined in this study.
Abstract