Analysis of damping impact vibration performance of air spring with negative stiffness

Abstract

Conventional air springs exhibit inadequate impact isolation performance under transient shock conditions due to inherent dynamic hysteresis in stiffness regulation, which leads to significant lag in stiffness response. To overcome the inherent limitations of the existing two paradigms—namely “structure-dictated-function” and “control-augmented-structure”—this paper presents a novel integrated negative-stiffness air spring architecture. Its key innovation lies in the incorporation of a controllable auxiliary chamber inside the main air chamber, eliminating the need for external complex mechanisms or high-bandwidth active control. By establishing a dynamic gas-coupling interaction between the main and auxiliary chambers, the system is designed to actively induce an internal negative-stiffness effect instantaneously upon impact, thereby counteracting the abrupt increase in primary stiffness and smoothing the shock load at the source. Through an integrated methodology combining theoretical modeling and experimental bench tests, this study systematically elucidates the regulatory effects of two critical design parameters—auxiliary chamber volume and valve opening—on the dynamic characteristics of the system. Results demonstrate that both the dynamic stiffness and the impact stiffness decrease monotonically with increasing auxiliary chamber volume and valve opening. The proposed configuration effectively achieves the intended internal negative-stiffness behavior, significantly attenuates impact-induced vibration, and mitigates stiffness hysteresis. This work verifies the feasibility of realizing transient negative stiffness via internal chamber coupling for shock suppression, offering a new design paradigm and practical guidelines for developing high-performance suspension systems with compact layout and fast response.