Performance Analysis Of Large Mine Vehicle's Hydro-pneumatic Suspension System

For the existing mine vehicles, there are two kinds of hydro-pneumatic suspensions: suspension with external accumulator and suspension with inner gas chamber. The first kind suspension is not convenient in installation and takes up too much space, and the second kind suspension always adapts the installation with rod chamber on the top and rodless chamber in below, which makes the impurity easy to invade the oil and gas suspension and affects suspension performance and service life. To overcome above shortcomings, this article designs a new type of hydro-pneumatic suspension with inner gas chamber, then an analysis of suspension's nonlinear stiffness and damping characteristics as well as their influencing factors is made based on the mathematical model of hydro-pneumatic suspension. Considering that there is a very big axle weight difference between the large-tonnage multi-axis mine vehicle is full loaded and light loaded, some bearing shafts are requested to be lifted to improve the transportation efficiency a nd economy of vehicle when it is light loaded. On the premise of not affecting the basic function of hydro-pneumatic suspension, a special hydraulic control system of hydro-pneumatic balanced suspension vehicle body height adjustment is designed. The control system has three functions: adjusting vehicle body height when it is stationary, elastic suspension and lifting some bearing shaft when vehicle is light loaded or the wheels fails in work. With the aid of MATLAB/SimHydraulics software, a first two axis hydro-pneumatic balanced suspension vehicle body height adjustment hydraulic control system is modeled. Then, a simulation of the specific implementation process of upper three functions is carried and a discussion of the influence of hydraulic components on suspension performance is made. In order to verify hydro-pneumatic suspension with inner gas chamber as well as hydraulic control system's performance on the real vehicle, a 3D model of hydro-pneumatic suspension is established based on the mechanical s ystem dynamics analysis software ADAMS/View and a co-simulation is carried between MATLAB/SimHydraulics and ADAMS/View. Finally, a discussion about the effects of hydraulic components on vehicle ride comfort in the index of body acceleration, suspension dynamic deflection and tire dynamic load is made.The analysis of this paper shows that the designed hydro-pneumatic suspension with inner gas chamber has great nonlinear stiffness and damping characteristics, and the designed hydraulic control system of hyd ro-pneumatic balanced suspension for adjusting vehicle body height could achieve vehicle lift, elastic suspension as well as single shaft lifting function. The co-simulation between MATLAB/SimHydraulics and ADAMS/View verifies that the designed system could function well on the virtual model of real vehicle. This article also illustrates that changes of hydraulic components' parameters has great influence on dynamic and static characteristics of the suspension system as well as the ride comfort of vehicle, which provides references on the design of hydro-pneumatic suspension and vehicle body height control system as well as the the choice of hydraulic components.