Theoretical Analysis And Simulated Research Of The Abs Based On The Reference Vehicle Speed Corrected By Acceleration

With the development of science and technology and the improvement of the people's standard of living, human's requirement of the vehicle security become higher and higher, especially the braking security. Anti-lock braking system (ABS) is a kind of device, which can regulate the wheel's braking force automatically, prevent the wheels from locking and acquire the best effect during braking. This device is significant to steering safety. So it has become one of the necessary parts of the top grade car.A theoretical analysis and digital simulation are carried out in this paper. The chief of the study is that the braking process of the vehicle based the basic fuzzy control theory and the fuzzy model reference learning control theory is simulated, in the hypothesis of the vehicle speed can be accurately measured and obtained that if the vehicle speed can be accurately measured, the effect of the ABS would be very ideal; but there is no costly effect sensor for vehicle speed that does not depend on measuring wheel speed at present. So this article put forward a new method which adopt the acceleration sensor to acquire the vehicle acceleration at first, then use it to correct the reference vehicle speed inreal time. As a result, it is very ideal. The main research work of this paper includes:(1) Introduce the basic principle, structure, arrangement scheme, the history, the present situation and the developing tendency of the ABS in detail based on a greal of literature.(2) The whole ABS models are established for the simulation requirement, including tire-road model, vehicle dynamic model, brake disk model, hydraulic system model and the controller model.(3) Investgated into the Control method of Logic Threshold Value, which was widely used in the present ABS products, then give a simulation research using the foreast control method.(4) The ABS system adopting the control algorithm based on the adhesion coefficient of the road surface is simulated. Then the advantages and disadvantages of this control way are analyzed in detail.(5) The ABS based on the basic fuzzy control theory and the fuzzy model reference speed control theory are analyzed and simulated, then compared them with the two ways above.(6) Under non-ideal circumstances, adopting a mathematical method to calculate the reference vehicle speed, then the ABS using this way is simulated, the error with the ideal circumstances is analyzed and the ways to correct this error are gived.