Advanced yaw control of four-wheeled vehicles via rear active differential braking

In this paper, the problem of active lateral dynamics control of four-wheeled vehicles during braking is addressed. In certain specific conditions, a vehicle may deviate from straight line trajectory even if the steering wheel is kept still and straight. By applying a differential brake pressure, it is possible to generate a yawing moment to recover the desired trajectory. An analytical model of the vehicle dynamics of interest is derived and validated against experimental data; the model dynamic analysis shows that its behavior is strongly affected by longitudinal velocity and deceleration. Hence, this dependence is taken explicitly into account by devising an LPV controller. The performance of the proposed controller is finally assessed both via simulation and on a test vehicle.