The report is concerned with the development of a method of measuring the demand on a driver's attention. For the experiment a visor-shutter translucent screen was developed whose light-dark ratio could be controlled and varied. Under mild traffic conditions a driver, when fitted with the device, would be expected to tolerate a relatively long dark interval while under heavy traffic conditions the driver would tolerate no interruption of his view of the road. The device was validated by determining the longest dark interval which could be tolerated when the car travelled at various speeds on a straight section of interstate highway as well as on a curved track. A formula was developed to explain the factors influencing attention demand and driver stress.
Abstract