An assessment of additional steering torque as a haptic signal to give drivers feedback from the vehicle in order to give lane-departure alerts or to support lane keeping is described. In two studies, driver performance and vehicle response were assessed in a practical study of haptic feedback conducted on a test track in a specially equipped vehicle. The first study was conducted on a total of 30 drivers and examined variations on the amplitude of the haptic signals. In a second study, with another group of 30 drivers, the focus was on the gradient of the signal. The RESPONSE Code of Practice requires that the signals used in driver assistance systems should be tested on driver groups which might perform less well than the average driver. Hence, both younger drivers and older drivers have been included in these studies. The analyses compared the results of these subpopulations with those from a group of experienced middle-aged drivers. The results do not indicate that age and experience influence the reactions times or perceptions of the signals. This finding was replicated in the second study. Furthermore, the results of the two studies show clear effects of amplitude and gradient of the haptic signal on drivers' perception and reactions. (Author/publisher).
Abstract