Four Parameter Evaluation Method of Lateral Transient Response

There are many meaningful numerical evaluations of vehicle dynamic performance. However, evaluation methods using one or two parameters have little practical use for development of new cars or for comparison of similar cars since drivers' preferences vary widely in various handling characteristics.

We developed the Four Parameter Evaluation Method. The parameters are extracted from lateral transient response data by curve fitting with a two degree of freedom model. Intuitively, we can recognize vehicle performance by arranging these four parameters in a rhombus. This expression is suitable for complex handling characteristics. The resulting rhombus pattern reflects a rather small difference between test cars including 4WS.