| The traditional passive suspension structure is poor in the ride comfort and driving safety of the vehicle,and the hydro-pneumatic suspension as a new suspension structure,combined with the traditional suspension technology and hydraulic transmission technology,can adjust damping,stiffness and Body height real time based on road conditions.It is conducive to improving the vehicle ride comfort and driving safety.At present,hydro-pneumatic suspension devices have been widely used in many fields of passenger cars and commercial vehicles.In this paper,the mathematical model of single-chamber hydro-pneumatic suspension is established with SUV as the target model.The influence of each structure and working parameters on the stiffness and damping characteristics of hydro-pneumatic suspension are analyzed.In order to improve vehicle ride comfort and driving safety,the damping of hydro-pneumatic suspension is optimized based on genetic algorithm.A new type of hydro-pneumatic suspension with adjustable damping,stiffness and height is designed,and the positive effect of optimized damping on vehicle ride comfort and driving safety is verified.The main work of this paper can be divided into the following aspects:1.The basic structure and principle of the hydro-pneumatic suspension are introduced.Based on the force analysis,the mathematical model is established and the stiffness and damping characteristics of the hydro-pneumatic suspension are simulated.2.Based on the influence factors of spring stiffness,frequency characteristics and damping characteristics of hydro-pneumatic suspension,the development interface of hydro-pneumatic suspension performance is developed,which provides a theoretical basis for the development of later hydro-pneumatic suspension.3.According to the requirements of ride comfort and driving safety,the genetic algorithm is used to optimize the suspension damping ratio under different road conditions,and the values of vibration responses such as vehicle acceleration,suspension dynamic load and dynamic deflection are compared before and after optimization,indicating that the optimization method has certain practicability.4.The method of parameter matching of composite hydro-pneumatic spring is put forward.The complete experimental scheme of the hydro-pneumatic suspension system is designed.The structural design of the hydro-pneumatic suspension damping unit is carried out and the damping structure of the hydro-pneumatic suspension which could improve the vehicle ride comfort and driving safety is verified.The hydro-pneumatic suspension developed in this paper not only achieves the damping,stiffness and height of the adjustable,but also has advantages over the traditional suspension structure in vehicle ride comfort and driving safety. |
