Effect of driving inactivity on driver's lateral positioning control: A driving simulator study

Overall on-road driving skill is a cumulated acquisition of driving skills learned during training period and furthered tempered with post-licensing driving exposure on the roads. Training serves to develop a person's basic driving skills to operate safely on the roads at first, while subsequent on-road driving hones the driving skills further. Inactivity from on-road driving can result in deterioration of driving skills. Particularly for the case of inactivity immediately following licensure, which is not uncommon in Singapore, the learned skills can degrade rapidly. This research aims to examine the effect of driving inactivity on the learned driving skill, i.e. lateral positioning control, specifically for young-inexperienced drivers. A series of experiments were conducted on a driving simulator for different subject groups involving active driver, novice driver (freshly-licensed driver), inactive driver (never ever drive upon licensure), and no licence subjects. The participants drove through a stretch of expressway under free-flow conditions, and lane positioning control was monitored. It is found that without on-road driving exposure, driving skills like maintenance of lane positioning control in terms of lane wandering and lane encroachment may deteriorate after some periods of inactivity, i.e. 3 months. The deterioration varies at different rate, with faster deterioration for more complex tasks. The skills level can regress close to un-trained level for complex driving tasks. The findings also suggest that on-road driving exposure is needed to not only retain but also to improve the lane positioning control skills.