This article describes research which investigates the effect of human ageing upon the drivers ability to steer their vehicles. Nearly 230 men, women and children aged between 4-88 years old were tested using a driving simulator. Both reaction time and steering ability were tested. The steering simulator consisted of a steering wheel and an accelerator and brake pedal, attached to a microcomputer and Visual display unit. The steering wheel could be set at various steering angles. Two values were used. One simulated an emergency lane change and the other simulated driving round bending roads. Two experiments were carried out: (a) compensatory tracking, where the driver had to minimize the difference in tracking between the derived curves and those displayed on the visual display unit, and; (b) "pursuit" tracking. The results showed that those subjects in their 20's had the shortest reaction times. This increased thereafter and increased markedly after the age of 70. Age was also found to affect other aspects of steering control and suggestions are made to improve the design of the car steering unit in order to compensate for this.
Abstract