In 1999, for the first time, new cars have become available in Europe with a system that can automatically activate a vehicle control independently of the driver. This system is Adaptive Cruise Control (ACC), the speed and headway control system, which is being offered as an option by Jaguar and Mercedes-Benz. Equipped cars can activate the throttle and even the brakes without the driver touching the pedals. This happens in response to the acceleration or deceleration of the preceding vehicle. ACC represents the first of many future such systems, which are likely to take over increasing aspects of vehicle control, both longitudinal and lateral. Research on ACC has been going on for over ten years, since at least Prometheus and DRIVE 1. And yet, in spite of a considerable number of studies, it is not possible to say for certain that ACC is a "safe" system, i.e. will not have the effect of increasing overall accident risk. This paper reviews the published studies of ACC and discusses their findings in terms of driver performance, workload, driver behaviour, short-term behavioural adaptation and long-term behavioural adaptation. ACC is not a single system with a single specification, but a category of system. The behaviour of the ACC varies between different manufacturers and can also be altered by driver input, in particular in terms of the selection of desired headway. The paper looks at the research findings on how driver performance and behaviour are affected by the ACC configuration. Finally, the paper addresses the issue of why it is not currently possible to conclude that ACC usage will not be detrimental to safety. It discusses whether this inability to come to any firm conclusion is acceptable in terms of an overall approach to managing the introduction of new vehicle systems. For the covering abstract see ITRD E113725 (C 22328 CD-ROM).
Abstract