Vehicle Semi-active Control Based On Parameters Sensitivity Analysis Of Hydraulically Interconnected Suspension

The suspension system is the important part of vehicle chassis system,it can buffer the impact force from the uneven road surface to the frame or the body,and attenuate the vibration so as to ensure the vehicle running smoothness.While,the design of suspension system needs to satisfy multiply paradoxical characteristic,such as the contradictoriness of comfort and ride.Recently,as a new advanced suspension system,the hydraulic interconnected suspension system have been researched.Due to wheels can be influenced by others,the hydraulic interconnected suspension system can be used to configure the stiffness and damping of the suspension independently,which can improve the handling stability of the vehicle without affecting the ride comfort.Therefore,this paper launched a series of research on hydraulic interconnection suspension system.The sensitivity analysis of hydraulic parameters is carried out by using the fuzzy grey correlation sensitivity analysis method,and the key hydraulic parameters are chosen to carry out the orthogonal optimization analysis based on the aim that suspension response,using the NSGA-? multi-objective optimization algorithm;the semi-active control is design based on the skyhook damping algorithm.The main contents of the dissertation are as follows:Firstly,a four-degree-of-freedom anti-roll half-car model is built in this paper,which is used to analyze and introduce the composition and working principle of the mechanical and hydraulic systems.Based on the transfer function and road excitation,the mechanical and hydraulic coupled system dynamic equations are derived in frequency domain naturally.Secondly,the research on the hydraulically parameters sensitivity to the hydraulically interconnected suspension dynamic response.The vertical mode and roll mode of suspension are analysis,obtained the grey correlation degree of hydraulic parameters.The results show that the valve accumulator and damping coefficient is the key parameter of hydraulically interconnection suspension.Then,based on the accumulator work pressure P1,precharge pressure P2,the hydraulic cylinder pressure leakage coefficient R1 and R2,connection inferior vena damping valve,the multi-objective optimization algorithm is introduced in this paper,improving the accuracy of the optimization results,solving the multi-objective optimization problem effectively,using the NSGA-II algorithm,based on the aim of ride and comfort performance.Finally,to improve the ride and comfort performance,the semi-active controller is designed using the skyhook,based on the time mode of hydraulically interconnection suspension,and it is simulated in the Matlab/Simulink,and the results show that the efficiency of the semi-active controller.