Abstract
The investigation presents an evaluation of four automobile taillight signal systems, an investigation of the motorists use of turn signals, a study of longitudinal control systems for platoon movement, and a study of passing decisions on a multi-lane expressway. An infrared source-sensor system has been designed and tested to provide the driver with a visual display of relative velocity and spacing between vehicles. Aerial photogramme trice methods have also been devised to aid in the studying of traffic flow phenomena.