Resettable‐inertance inerter: A semiactive control device for energy absorption

Abstract

Semiactive control systems are based on formerly passive mechanical devices whose characteristics are adjusted in real time by active means. They can be classified into variable-damping dampers, variable-stiffness springs, and variable-inertance inerters. Similarly to the case of "variable-stiffness," two possibilities are devised for inerters: "independently-variable inertance," where inertance can increase or decrease continuously at any instant of time, and "resettable-inertance," where it can increase only at instants where relative velocity is zero. By duality with resettable-stiffness springs, a resettable-inertance inerter (RII) is composed of an inerter that can suddenly be disconnected from the vibrating system and blocked in order to eliminate kinetic energy. Studies on "independently-variable inertance" have been carried out recently, but there are still no studies on "resettable inertance." This paper presents an analytical numerical study on RII, for an energy-based control law, through the mathematical model of a mechanical implementation. By simulation of a numerical example that considers a SDOF system with three different devices, the performance is demonstrated for energy absorption and vibration reduction. Moreover, closed-form expressions for the equivalent-linear inertance, stiffness, and damping are found for the resettable devices and validated through the numerical example. Main conclusion is that RII adds equivalent damping without dynamically stiffening the structure. Besides, the absorbed energy can be dissipated and/or harvested in time intervals in which the RII is uncoupled from the structure.

Dynamic performance of structures with clutching inertia‐damping system: Theoretical study

“…Consequently, the actual output model extremely differs from the ideal model, and the performance does not achieve the desired results. (3) In terms of implementation, achieving the ideal clutching inertia model in a semi‐active or intelligent control manner is relatively complex, 38 which increases the difficulty in engineering design and application.…”

Analysis of inertance and damping double‐skyhook control strategies for a semi‐active device combining an adjustable inerter and damper

“…These works opened up investigations on application of semi‐active inertance control to structural vibration control in the sense that it is utterly different from stiffness and damping controls. Garrido et al 26 developed a resettable‐inertance inerter(RII), which was analytically and numerically investigated by a mathematical model mechanically implemented for the energy‐based control law of RII. By designing a hierarchical adjustable semi‐active inerter, Wang et al 27 proposed two acceleration‐velocity‐based control strategies and evaluated the vibration isolation performance of the device using four performance indicators.…”

Input energy reduction principle of structures with generic tuned mass damper inerter

“…The inerter-based system is widely accepted and effective for vibration control 1,2 and has attracted many researchers working on the relevant invention of devices [3][4][5][6][7] and optimal designs. [8][9][10][11] In recent literature, the performance evaluation and benefits of inerter-based systems for the protection of building structures, [12][13][14][15][16][17][18] wind turbine towers, 19 storage tanks, 20 and semi-submersible platforms, 21 the vibration suppression of cables 22 and machines, 23 and the wind-induced vibration mitigation of tall buildings 24,25 have been examined.…”