VIBRATION SUPPRESSION BY VARIABLE-STIFFNESS MEMBERS

An active vibration suppression concept, by varying the stiffness of a new type of variable-stiffness structural member, is proposed and investigated. The characteristics of this type of variable-stiffness system is shown to be different from previously studied types. The active vibration suppression with this type of variable-stiffness member is shown to be always stable. A theoretical investigation on a single-degree-of-freedom system shows potential high efficiency for this type of variable-stiffness system due to its unique hysteretic characteristics. Two different types of control logic are proposed for realistic multi-degree-of-freedom structures with multiple variable-stiffness members. Numerical simulations demonstrate the effectiveness of the proposed strategy. Active vibration suppression experiments of truss structures are performed by using a variable-stiffness member and the proposed control logic, demonstrating the effectiveness of the proposed technique in actual structures.