The relation between speed choice and steering performance during curve negotiation was examined in a driving simulator. The hypothesis was that curve radius and steering competence both affect steering error during curve driving, resulting in compensatory speed choice. In this, the control of safety margins was assumed to operate as a regulatory mechanism. Smaller curve radii resulted in a larger required steering wheel angle, and steering error increased linearly with required steering wheel angle. Participants compensated for this by choosing a lower speed, such that the time to line crossing to the inner lane boundary was constant over all curve radii examined. Steering competence was measured during straight-road driving. Poorer steering competence also resulted in larger steering errors, which were compensated for by choosing a lower speed, such that the safety margin to the inner lane boundary was unaffected by steering competence.
Abstract