A study of the effects of mobile telephone use and control unit design on driving performance

Concern about the effects of mobile telephone use on driving control led to the development of a methodology for evaluating driving performance. A summary of the methodology is presented along with the results of a study comparing the effects of dialing a telephone to the effects of adjusting the car radio. A detailed account of a study of the effects of alternative control unit designs is provided. Three types of dials were implemented for this study. They are a rotary dial, a pushbutton dial, and a pushbutton dial-in-handset. Three mounting locations for the pushbutton dial were studied: on the dashboard, in the dashboard, and in the visor area. The rotary dial and the dial-in-handset models were mounted on the transmission tunnel. The results of the study indicate that the design of a dial that is located within the reach and sight of the driver has little effect on driving control. User preferences favored a pushbutton dial mounted in the dashboard area.