ABSTRACT
In an average car it is now common to find electrical switch controls for windows, roof, mirrors, seats, stereo and sometimes an on-board computer. In addition, the complexity of more conventional controls has increased as the functional options have grown. For instance, the wiper controls may now incorporate a rear-wipe function, an intermittent
rate of wipe that can be varied and even a headlight wash/wipe. The driver is faced with a dual problem of new, unfamiliar and perhaps rarely to-be-used functions rapidly appearing in new models, as well as a general lack of manufacturer standardisation of controls from the points of view of both location and direction-of-motion of operation. New functions are supposedly introduced to provide the driver with greater means of control and to increase comfort and enjoyment but, as Schlegel (1992) points out, ‘the modern automobile is a complex system with accessories and features which may distract the driver rather than complement safe vehicle operation’. It is clearly incumbent on the manufacturer to ensure that controls for new functions minimise the additional workload required to benefit from them. It is reported by Perel (1983) that drivers of an unfamiliar car are two to three times more likely to be involved in an accident than drivers of a familiar car.
