An Experimental Investigation on the Characteristics of Automotive Air Spring

In order to control air suspension system, the air spring characteristics, stiffness and effective area were experimentally researched through the static and dynamic tests. The displacement signal with large amplitude and low speed was executed on the air spring piston in the static test. Using test data, the static stiffness with different initial pressure and the effective area were obtained. It is found that the lowest value of the static stiffness is about 10KN/㎜ for various initial pressures and that the effective area is influenced more by the piston contour. In dynamic test the harmonic displacement signal with various frequencies was applied. The test results show that the hysteresis in one Force-Displacement cycle becomes better when excitation frequency increases, but does not change too much as the frequency is higher than 1㎐. And the dynamic stiffness goes up with increasing of the initial pressure and the excitation frequency.