ADAPTIVE LIGHTWEIGHT CFRP STRUT FOR ACTIVE VIBRATION DAMPING IN TRUSSSTRUCTURES

For the purpose of active damping and suppression of vibration in adva nced composite truss structures a new adaptive lightweight strut was d eveloped. It was based upon a previously developed multi-purpose CFRP sandwich strut with integrated load transfer elements. Into this strut . which exhibits excellent mechanical properties related to the struct ural weight. a piezoceramic high-load stack actuator with an expansion capability of 55 mu m was integrated. A spacial design using a compos ite sleeve allows the tailoring of the strut stiffness particularly wi th respect to high active tension forces. The measurement of the dynam ic strut response is provided by a surface bonded and electrically iso lated PVDF film sensor. Tests of the adaptive strut in an antenna-supp orting composite truss structure established a nearly complete suppres sion of externally excited disturbing vibrations. Due to the structura l concept the new adaptive strut is well suited for active vibration c ontrol under high strength and stiffness requirements.