Abstract
This paper presents a construction of the new vehicle dynamics theory for transient state. The paper starts with the definition of complex cornering stiffness, which is the same as the equivalent cornering stiffness when phase lead time is taken into account. The relationships among natural frequency and damping coefficient of plane motion and the phase lead time is also formulated. Moreover, the paper theoretically analyzes the driver-vehicle system; the result of it is that the large phase lead time of the rear axle enhances the stability of the system. Furthermore, the paper formulates several dynamic characteristics of rear suspensions as an application of the theory; its result yields the desirable combination of rear suspension characteristics. Furthermore, vehicle experiments verifies the studies. At the end, the appendices show two example of applications of the theory as follows: 1) the effect of the tire first order lag on vehicle dynamics; 2) an identification of actual vehicle dynamic performance.