As part of a large scale questionnaire study (N = 791), English car drivers rated the usefulness and acceptability of systems to warn about, or to override driver preferences for, speed and headway. A system that `Warns you to adjust your speed to the conditions' was deemed the most useful and acceptable. A system that `Automatically adjusts your speed so you keep to the limit' was considered the least useful and acceptable. Telematic devices which limit the driver's freedom to violate the rules of the road were least favoured by drivers under 45, male drivers, drivers from the higher social classes and from medium and high income groups, from the least experienced drivers, from high mileage drivers, from drivers of large-engined cars, and from those who drove as part of their work. Respondents also nominated their 'normal' and 'preferred' speeds on four road types. Those car drivers who find automatic speed control not at all acceptable nominated higher normal and preferred speeds on motorways, other main roads, and rural roads - though not on suburban roads. Thus those whose driving is most in need of it are those least likely to favour automatic regulation of their speed. For the covering abstract see ITRD E113725 (C 22328 CD-ROM).
Abstract