Study On Yaw Stability Control Of Vehicle

Under rapidly steering or lane change maneuver at high speed, the vehicle tend to produce great yaw moment and result into sideslip motion, moreover, in case of starting to slip, it will be rapidly lose controls. In this paper, based on the abroad achievements in this field, sideslip motion of the vehicle rapidly steering is analyzed, in order to control it, the control logic is designed and several methods are implied.The actual model and the desired model of the vehicle rapidly steering is built, the variation law of vehicle motion state is researched, then research on relation between vehicle sideslip motion and motion state, and the case of vehicle sideslip is also decision. By analyzing the instability, the yaw moment used for restoration stability can be calculated, and then the best braking wheel can be selected. That is, the vehicle stability is improved through the yaw moment generated from braking force. In this paper, the fuzzy control method for vehicle yaw stability is built, and the validity of the control strategies is proved through the simulate results; the conclusions were drawn initially as followings:(1) The validity of the control strategies are proved through the simulate results, comparing and analyzing the experiment results, it is shown that:Based on fuzzy control for vehicle yaw stability, amplitude value of the yaw rate and the side slip angle are reduced, therefore, vehicle stability on turning lane is improved.(2) By comparison, the control effect based on combined control method is better than that of DYC only.(3) Road adhesion coefficient, vehicle speed and steering characteristic had definite influence on control effect (This paper only consider the difference of road adhesion coefficient). The vehicle instability is easy to happen along with the lower of road adhesion coefficient and increasing of vehicle speed, by this, it can be seen that the vehicle based on stability control has many advantages over the vehicle of no control, in the contrary; the control effect is not evident.