This paper is concerned with the H ∞ and H 2 optimization problem for inerter-based dynamic vibration absorbers (IDVAs). The proposed IDVAs are obtained by replacing the damper in the traditional dynamic vibration absorber (TDVA) with some inerter-based mechanical networks. It is demonstrated in this paper that adding one inerter alone to the TDVA provides no benefits for the H ∞ performance and negligible improvement (less than 0.32% improvement over the TDVA when the mass ratio less than 1) for the H 2 performance. This implies the necessity of introducing another degree of freedom (element) together with inerter to the TDVA. Therefore, four different IDVAs are proposed by adding an inerter together with a spring to the TDVA, and significant improvement for both the H ∞ and H 2 performances is obtained. Numerical simulations in dimensionless form show that more than 20% and 10% improvement can be obtained for the H ∞ and H 2 performances, respectively. Besides, for the H ∞ performance, the effective frequency band can be further widened by using inerter.

This paper is concerned with the problem of analysis and optimisation of the inerter-based isolators based on a "uni-axial" single-degree-of-freedom isolation system. In the first part, in order to gain an in-depth understanding of inerter from the prospective of vibration, the frequency responses of both parallel-connected and series-connected inerters are analysed. In the second part, three other inerter-based isolators are introduced and the tuning procedures in both the H ∞ optimisation and the H 2 optimisation are proposed in an analytical manner. The achieved H 2 and H ∞ performance of the inerter-based isolators is superior to that achieved by the traditional dynamic vibration absorber (DVA) when the same inertance-tomass (or mass) ratio is considered. Moreover, the inerter-based isolators have two unique properties, which are more attractive than the traditional DVA: first, the inertance-to-mass ratio of the inerter-based isolators can easily be larger than the mass ratio of the traditional DVA without increasing the physical mass of the whole system; second, there is no need to mount an additional mass on the object to be isolated.

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