Multi-objective optimization and experiment of a bio-inspired floating slab isolation track

Abstract

In order to break through the limitation of the "single-point" design of Quasi-Zero Stiffness (QZS) property and satisfy multiple performance objectives, this study proposes a novel bio-inspired vibration isolator integrating the biological leg configuration and flexible joints, and conducts nonlinear analysis and experimental verification. Bio-inspired by the frog legs, the proposed isolator is a multilink structure consisting of two symmetrical bionic legs with long links (as bones) and scissor-like units (as joints). It is mounted on the lower level of the floating slab isolation track, which is simplified as a two-degree-of-freedom isolation system. For the actual requirement in the floating slab track, three performance indexes, including load carrying capacity, dynamic stiffness, and stability of isolation performance, are considered in structural optimization. Based on these optimization objectives, we carry out the multi-objective Pareto design criterion to achieve a collaborative optimization of the mechanical properties. Additionally, the experimental prototypes and low-frequency isolation experiments are carried out to verify the effectiveness of the multi-objective Pareto optimization framework. This bio-inspired isolator can effectively coordinate large loads and low-frequency vibration isolation problems and has promising applications in the field of rail transportation.