Experimental investigation of different actuator technologies for active vibration control

In a smart structure, where the objective is active vibration control, there is a requirement for actuators, sensors and an electronic controller. Although there have been significant advances in controller design, in terms of software, hardware and control algorithms, this has not been matched in the design of the transducers. This note is concerned with the various actuator technologies for active vibration control. A set of experiments is conducted on five actuators, three of which use piezoelectric driving elements and the other two are magnetostrictive and electrodynamic. The experimental data for each of the actuators are compared by using a simple two-port model which facilitates a comparison of the actuators' mechanical and electrical properties that are important for vibration control actuators. A method of comparing the mechanical output from both voltage and current driven actuators on a composite graph is proposed. It is also shown that with present technologies, actuators that can deliver large displacements generally have a low stiffness and can only generate moderately low forces. The opposite is also true.