Manufacturing and Active Control Testing of Active Composite Panels With Embedded Piezoelectric Sensors and Actuators: Wires Out by Cut-Holes and Embedding

This work presents manufacturing and testing of active composite panels (ACPs) with embedded piezoelectric sensors and actuators. The composite material employed here is a plain weave carbon/epoxy prepreg fabric with about 0.3 mm ply thickness. A cross-ply type stacking sequence is employed for the ACPs. The piezoelectric flexible patches employed here are Active Fiber Composites with 0.33 mm thickness. Composite cut-out layers are used to fill the space around the embedded piezo patches to minimize the problems associated with ply drops in composites. The piezoelectric patches were embedded inside the composite laminate. High-temperature wires were soldered to the piezo leads, insulated from the carbon substructure by high-temperature materials, and were taken out of the composite laminates employing both cut-hole and embedding techniques. The laminated ACPs were co-cured inside an autoclave employing the cure cycle recommended by the composite material supplier. The Curie temperature of the embedded piezo patches should be well above the curing temperature of the composite materials as was the case here. The manufactured ACPs were trimmed and then tested for their functionality. Vibration suppression as well as simultaneous vibration suppression and precision positioning tests, using Hybrid Adaptive Control techniques were successfully conducted on the manufactured ACP beams and plates and their functionality were demonstrated. The advantages and disadvantages of ACPs manufactured by taking the wires out employing cut-holes and embedding techniques, in terms of manufacturing and performance, are presented.