Experimental demonstration of a vibration absorber using braid-sheathed fluidic flexible matrix composite tubes

Fluidic flexible matrix composite (F²MC) tubes are a novel type of lightweight, low-profile passive fluidic vibration treatments for structures. Two pairs of F²MC tubes are installed onto a laboratory-scale helicopter tailboom structure and interconnected through a fluidic circuit, resulting in a tuned vibration absorber. The experimental frequency response of the absorber-treated tailboom shows a response amplitude reduction of over 70% for the first vertical bending mode. By partially restricting flow through an orifice in the fluidic circuit, a damped absorber is achieved that adds nearly 8% damping to the first vertical bending mode. The effect of fluid prepressure and tailboom forcing amplitude are also studied. The experimental results show excellent agreement with model predictions.