Applied Research On New Magnetorheological Damper Used In Loader Suspension System

Scientific and technological progress with the times, people driving the vehicle stability and ride comfort more demanding, so semi-active suspension technology sessions by academic and industrial attention. Magnetorheological (MR) fluid as a novel smart material, applied magnetic field can achieve rapid liquid and semi-solid transformation, the conversion process is controllable and reversible. MR fluid damper based on this characteristic of the magnetic design, with fast response, good controllability, low power consumption and the structure is relatively simple, the advantages of large output force, very suitable for application in the vehicle suspension system. For those reasons, the new MR damper which is self-fed based on reasonable MR fluid was designed in this paper, and it is equipped in the suspension system of ZL50 wheel loader, its significance lies in the theoretical analysis and simulation test, come to this MR damper design principles and methods, thus for the early development of practical application that can put energy saving and high reliability semi-active MR suspension provide valuable rack system design basis and means of implementation.The specific content of the paper is as follows:In chapter 1, the background and significance of research were described. The MR fluid, MR damper, vehicle suspension system and suspension control system's status and problems were overviewed at domestic and abroad; for the problems of ZL50 wheel loader semi-active MR suspension system, the main research of this paper were proposed.In chapter 2, the self-fed MR fluid damper was designed which is one single out of the pole, the output power of the damper was established based on Bingham model. The new MR damper's mechanical structure and magnetic circuit were optimized by multi-objective optimization. According to the power required of the damper, the feed part of the damper was designed which is a power generator. The model of the damper was created in Matlab/Simulink according to the new MR damper mechanical model. The external characteristics were analyzed.In chapter 3, the mathematical model of the sinusoidal excitation road surface was established; the index of suspension system performance was brief introduced; the suspension systems were established; The stability of semi-active suspension system were determined, its transfer function were derived, its amplitude-frequency characteristics were analyzed; according to the established semi-active suspension system, the response of the suspension system was analyzed when its parameters change.In chapter 4, the observability and controllability of the suspension system was analyzed; the linear quadratic optimal controller, fuzzy controller, fuzzy neural network controller and self-fed controller were designed, the four control strategies were analyzed in the Matlab/Simulink, the suspension system's performance were analyzed and compared under the four control strategies.Finally, this paper's research work and results were summarized; The shortcomings of this paper were concluded and the future research work was look-ford.