Inertial amplification metastructure absorber for lightweight vibration control

Low-frequency flexural resonances in complex engineering piping systems pose severe threats to structural integrity. Traditional passive vibration control methods often require substantial parasitic mass, violating the stringent lightweight constraints in modern aerospace and transit applications. To overcome this fundamental bottleneck, this work proposes a novel inertial amplification metastructure absorber. By leveraging a meticulously designed kinematic topology, the mechanism geometrically amplifies a minimal physical mass into a massive apparent inertia under ungrounded boundary conditions. To achieve absolute suppression of the global maximum amplitude, the norm optimization driven by the particle swarm optimization algorithm is conducted. The evolutionary process reveals the underlying physics of the inertial mechanism, demonstrating that minimizing the non-amplifiable top dead mass is imperative for maximizing the kinetic energy absorption capacity. The analytical model is thoroughly validated through three-dimensional finite element analysis. For a representative flexible pipe system, the proposed absorber operates under an extreme lightweight constraint with a mass ratio of approximately 0.5%, yet it successfully generates an apparent inertia that is more than four times its own physical mass. Acting as a highly efficient localized energy sink, the mechanism achieves a 46.5% reduction in the global maximum steady-state amplitude and exhibits rapid transient energy dissipation. This study provides a new paradigm for extreme lightweight vibration mitigation in complex engineering structures.