Dynamics of piezoceramics-based mass and force actuators for rotating machines

In the past decade, it has become more and more common to install active vibration control devices on rotating systems like grinding machines, tooling centers, industrial fans and drive shafts. In the present research, two innovative actuation concepts for such devices are evaluated. The first device is a force actuator based on piezoceramic fibers, which has a low power consumption and high dynamic range. The second device is a mass redistribution actuator based on two piezoelectric ultrasonic motors, which is smaller and faster than conventional electromagnetic devices. At the basis of the analysis are rotor dynamic finite element models including actuators, sensors and feedback controllers. In simulations and experiments with device one, feedback control and scheduled feedforward control are considered. It is shown experimentally that the unbalance response at a critical speed can be reduced by some 97%. In experiments with device two, the positioning speed is determined.