Eigen-structure assignment problem for an undamped structural system is referred to as that a feedback matrix G∈Rm×n is chosen properly so that the quadratic pencil Qc(λ)=λMa-Ka-BG has a prescribed subset of eigenvalues and eigenvectors.

In this paper, we discuss the optimal control problem for an elastic robot system by regarding the damping coefficient of structure as the control variable.

Parameter effects of the main controlled anisotropic layer on structural damping of alternately laminated damped structures;

Modal damping optimization for general damped structures;

The development history of the damping materials is retrospected and the research status of polymer,polymer composites and structure damping materials is summarized subsequently.

The structure damping is a non negative function.

Recently developed composite damping structures indicate that various damping requirements can be met through simple composition of several damping materials.

And several composite damping structures w ere introduced, and some analysis about their working mechanism were given.

We use restrained viscoelastic damping structure to reduce vibration in combination with sound absorption, insulation and suppression techniques for integrated control,and good result has been obtained in noise reduction.