Additive manufacturing of active struts for piezoelectric shunt damping

One strategy to deal with unwanted vibrations of lightweight structures is to actively control systems using integrated actuators, such as piezoceramic multilayer actuators. In the presented research work, selective laser melting is used to manufacture active struts by integrating multilayer actuator into a metallic, monolithic housing. Besides the fulfilment of manufacturing constraints (e.g. low volume and individualization), a major objective of this study is to demonstrate the potential of selective laser melting for application tailored smart components. A truss structure is used as demonstration platform. Based on experimentally validated numerical models of the truss structure, a beneficial position of the active strut and the mode to be damped are determined. A model of the multilayer actuator and corresponding housing allows the dimensioning of the housing stiffness to maximize the electromechanical coupling. Thus, an efficient resistive resonant shunted system can be achieved. Numerically designed active struts with specific stiffnesses are manufactured and experimentally characterized. Measurements with connected RL-shunts using the active struts are performed and compared to the original system. Results indicate an efficient damping of the desired mode by means of application tailored active struts. The presented procedure allows rapid design of versatile actuator housings for an optimized electromechanical coupling.