Research On Characteristics And Self-Adaptive Mine Vehicle Hydro-Pneumatic Suspension

With the continuous development of modern vehicle industry technology,the requirements for vehicle performance were gradually increasing.The application of oil and gas suspension was also becoming more and more widespread.It integrates the traditional suspension technology and hydraulic transmission control technology together,with good non-linear characteristics and vibration damping performance,which can meet people’s requirements for vehicle smoothness and stability,therefore,it was widely used in senior cars,engineering machinery vehicles(such as mining vehicles)and military vehicles.The suspension was an important device connecting the body and wheels,and was a key component affecting the driving performance of the vehicle.Therefore,by studying the characteristics of oil and gas suspension and adaptive control methods,etc.,the overall performance of the vehicle can be greatly improved.In order to improve the performance of oil and gas suspension and the ability of the suspension to adapt to the external environment,the research on active control of oil and gas suspension was getting more and more attention.This research was mainly carried out through the nonlinear modeling of oil and gas suspension and active control research as the idea,considering the different effects of different practical situations on the oil and gas suspension system,and designing the fuzzy PID controller by using the combination of fuzzy control and PID control method.This paper takes mining vehicles as the analysis model,and the specific research was as follows:(1)The classification,structural composition and working principle of vehicle oil and gas suspension were analyzed.(2)Based on the literature,the structure,types and characteristics of oil-air suspensions,as well as the development status at home and abroad,are introduced.For the nonlinear and damping characteristics of the oil-pneumatic suspension system,the mathematical model of nonlinear stiffness and damping of oil-pneumatic spring was established.And the simulation analysis and comparison of body acceleration,suspension dynamic disturbance and tire dynamic deformation are carried out in MATLAB/Simulink software.It was concluded that the damping and nonlinear stiffness performance of the nonlinear two-stage accumulator oil-air suspension was better compared with the conventional liquid oil-air suspension.(3)Theoretical modeling of the pavement excitation model for oil and gas suspensions was performed.The pavement excitation models used include the random pavement model and the bump pavement model,and the mathematical expressions of the models were derived.The pavement models were constructed by MATLAB/Simulink software,and the time domain diagrams of the two models were obtained.And the performance of the vehicle was evaluated and analyzed by using the vertical acceleration of the body,dynamic wheel load and dynamic travel of the suspension.(4)The working principles of PID control and fuzzy control are applied to build a simulation model of PID control for active oil-pneumatic suspension system,and fuzzy PID controller was designed by combining fuzzy control and PID control.Through the simulation of three performance evaluation indexes,a comparison was made and it was concluded that for the active suspension system,the use of fuzzy control can improve the performance of the suspension system,which was better than the use of PID control.(5)The control algorithm of the active suspension was derived by studying the self-correcting control adaptive system.The suspension damping coefficient,stiffness and elasticity were automatically adjusted according to the road conditions to achieve self-optimized control of the suspension.Simulation tests using MATLAB/Simulink software conclude that the use of fuzzy control methods enables self-optimized control of the active oil-pneumatic suspension.The self-correcting adaptive system enables the vehicle suspension system to achieve effective vibration damping in various states,which significantly improves the smoothness and comfort of the vehicle.