Research And Experiment Of ABS Logical Threshold Contol For Passenger Vehicle

With the development of automobile industry, the vehicle velocity and is increasing, and the density of running vehicle on the road is larger. The requirement on the performance of running vehicle for security from people is higher and higher. Anti-Lock Brake System (ABS) is to prevent wheel lockup, to ensure optimal stability and the least distance during the hard braking. From the 1980s, the ABS anti-lock braking system has been the automobile's initiative secure equipment, and obtained the widespread application in the world. In the developed country, ABS was already on automobile's standard fitting at present.Based on domestic and international research, the article analyzes the advantages and disadvantages of each control algorithm, through research control theory, the article analyses the calculation method of reference speed, the comprehensive slope method and the comprehensive method was put forward based on adaptive reference speed method. This method is not only speed revise reference for the initial value, still can update according to the slope before a control cycle, make more accurate reference speed calculation, although this approach relies on the last cycle of data, having certain hysteresis, but simulation results show that meet the control requirements.Pavement recognition of control logic is very important. This paper uses interpolation method of pavement of identification, in order to better control the best sliding rate. This method not only able to identify the specific definition garage by road, still can go interpolation method of identifying the current roadside real approximate optimal sliding rate, to a certain extent, increased recognition accuracy.At present, the ABS control algorithm has many kinds of method, most universities and the development facilities want to seek for a kind of simply and the effective method in the control algorithm. The logical threshold control algorithm is to be applied quite widely on the vehicles, and obtains the universal approval.This paper firstly introduces the common ABS control methods, and analyzes the advantages and disadvantages between each control algorithm. Through the study of the control theory, this paper analyses the calculation method of reference speed, and has putted forward a simple and effective road identification strategy; has established ABS controller based on logical threshold control algorithm. Then using the software VEDYNA an appropriate vehicle model is established. Through off-line simulation, the control algorithm of objective parameter also is identified and adjusted. Through the hardware in the loop experiments, the simulation validation has been done on the different friction coefficient roads, and based on the test data we compares the braking ABS function on different friction coefficient roads. This is to test this paper involves rationality and usability of ABS controller referenced by this paper. Data shows the controller in high friction coefficient road has good braking effect; low adhesion pavement control is not quite stable.This subject is based on the actual project, utilizing the existing laboratory hardware in the loop test we make the simulation analysis, and test the car validation, which has certain practical significance ABS development research.