EVALUATION OF AUTOMOBILE HANDLING TEST PROCEDURES USING A VARIABLE CHARACTERISTIC CAR

Although it is agreed that production automobiles vary widely in their lateral handling quality, the identification and objective specification of "optimum" handling characteristics has proved a difficult problem. Evaluation of handling quality requires the selection of (a) vehicle characterisations that can be objectively determined and are relevant to the driver's control needs, (b) steering tasks which are representative of critical real-life manoeuvres and which "exercise" the vehicle dynamics, and (c) performance measures which are relevant to handling quality and reliably discriminate between different vehicles. These aspects of test procedure design have been investigated experimentally using the Melbourne University variable characteristic car (VCC). Both "free control" and "fixed control" vehicle parameters have been varied in steering tasks which involved highway curve negotiation, a double lane change, a slalom course and disturbance regulation, including both discrete pulse and continuous random steering disturbances. A large number of subjective and objective performance measures have been investigated. Experiences gained in the design of test procedures are described. The various handling parameters, tasks and measures are compared and evaluated. Interactions between handling parameters are demonstrated and recommendations are made for "acceptable" and "optimum" ranges of vehicle handling characteristics. (Author/TRRL)