Metro Vehicle Air Spring Load-bearing System Dynamics Analysis And Weighing Error Research

The accuracy of metro vehicles weighing system is affected by the dynamic features and load capacity of air spring, The relationship between air pressure and load directly affect the weighing error. The vertical mechanical model and nonlinear dynamic model of air spring are established. The finite element mesh model is established to analyze the dynamic characteristics of air spring, The reasons for metro vehicles weighing error are analyzed. A new Formula for calculating the load based on pressure is derived, and validated with experimental data. Research in this paper is of significance to the dynamic characteristics analysis of air springs and the solution of vehicles weighing error that has a requirement of high performance.Main contents and methods of this paper are as follows:1. The vertical mechanical model of air spring and the vertical stiffness formula of air spring are studiedBased on the he working principle of air springs, combined with the gas state equation, the vertical air spring mechanical model is studied. The bond graph model of air spring is established by the 20-Sim software, and the vertical mechanical characteristics of air springs is analyzed. The main factors affecting the mechanical properties of the air spring are find. The damping is related to the hole diameter between chamber body and the additional chamber.The relationship between gas pressure and load is find.2. Consider the mass flow between body chamber and the auxiliary chamber, the vertical nonlinear dynamic model of air spring is established, the nonlinear dynamic characteristics is studied.The vertical nonlinear dynamic characteristics of air springs is studied by simulink modeling method, calculated by matlab software. The relationship between the volume and the chamber pressure is studied,the relationship between the displacement and the load is studied.3. The mechanical properties of its vertical finite element is analyzed by the nonlinear finite element model of the air spring.The initial pressure,cord angle and the auxiliary chamber volume of air spring, affect the vertical static and dynamic stiffness The relationship between static and dynamic stiffness is studied.The finite element model of air spring is established by using ABAQUS, and the vertical static characteristics are analyzed by the ABAQUS/Standard. The vertical static stiffness are related with the initial pressure, cord angle and additional parameters such as chamber volume of the air spring. Its dynamics, obtained under different initial pressure of the dynamic stiffness are analyzed by using the ABAQUS/ Explicit. The excitation frequency on the dynamic stiffness of air spring is studied.4.The reasons for metro vehicles weighing error are analyzed. A new formula for calculating the load based on pressure is derivedThe reason of the metro vehicle weighing errors system is analyzed. The error mainly from pressure measurement, dynamic response and formula. A new Formula for calculating the load based on pressure is derived, and validated with experimental data. The results proved to be correct.