Research On Brake Control Strategy Of Four-wheel Independent Drive Electric Vehicle Considering Driver's Braking Characteristics

With the development of modern vehicle electrification and intelligence,people's demand for vehicles is no longer a simple means of transportation,and the requirements for humanization of vehicles,such as intelligence and comfort,are getting higher and higher.With the development of electronic vehicles,the four-wheel independent driving electric vehicle will become the main form of the future vehicle.At the same time,the four-wheel independent driving electric vehicle has great advantages in the intelligent and humanized design of the vehicle.Based on the National Natural Science Foundation of China “Study on dynamics control for four wheel independent drive and steering electrical vehicle considering driving characteristic(51675257)”,the driver's braking characteristics are studied,and the driver's braking characteristics are integrated into the design of the four-wheel independent driving electric vehicle brake control strategy to achieve the "vehicle adapt to human" vehicle control and to meet the growing human needs.First,the driver's braking characteristics are classified.Based on the driving simulator simulation platform,design the test conditions and collect the data values of the vehicle speed,brake deceleration,brake pedal opening change rate of brake pedal opening and the relative distance during the driver's braking process.The M-language program of MATLAB software is used to extract the eigenvalues of the experimental data.The fuzzy C-means,Gaussian mixture model algorithm and K-means algorithm are used to cluster the data into three categories,analyze and compare the clustering results of three clustering methods,which respectively represent different driver braking characteristics.And the reasonable classification of the driver's braking characteristics is achieved.Secondly,a driver braking characteristic identification model is established and the match and verification of braking mode are performed.Gaussian mixture model is used to offline identification of the driver's braking characteristics.the classification data is used to train the BP neural network module and establish the online identification model of the driver's braking characteristics.The tests show that both the offline identification model and the online identification model can accurately identify the driver's braking characteristics.The drivers with different braking characteristics are selected to test to determine the braking torque compensation coefficient of different braking modes,and carry out experimental verification and driver's subjective evaluation.Thirdly,the research on the brake control strategy of the four-wheel independent drive electric vehicle considering the driver's braking characteristics is carried out.The braking control strategy is designed,and the different braking modes for the drivers with different braking characteristics are matched.Braking torque distribution relationship between the front and rear axles of the four-wheel independent drive electric vehicle is determined.Finally,the vehicle dynamics software CarSim and Matlab/Simulink are used to establish a four-wheel independent drive electric vehicle simulation model,and the experimental conditions are designed to verify the control strategy.The verification results show that the researched regenerative braking control method can effectively reduce energy loss and recover energy under the premise of ensuring the stability of four-wheel independent drive electric vehicles,and the research of the composite brake ABS control method realizes the anti-lock function of the four-wheel independent drive electric vehicle under various braking strengths.