Hybrid amplitude and vibration control for a small-scale linear drive with two sliders magnetically spring-loaded

This paper proposes an amplitude and vibration control for a small electric linear actuator consisting of two independently controllable sliders operated in resonance. Therefore, the sliders are axially spring-loaded by permanent magnets designed to match an operation frequency of about 50 Hz. One slider provides an adjustable oscillation amplitude, while the second one is utilized to reduce axial vibrations of the common housing and noise strongly induced by the first one. The overall systems result in a three-mass oscillator taking into account the movement of the common housing. To control the amplitude and vibration the derived model is transformed into an averaged model using the fundamental Fourier components. Based on this model a multivariable controller is designed taking into account the two different objectives for the amplitude and vibration control. Beside the design of the developed small electrical linear drive, the paper offers modelling aspects and the design as well as the experimental validation of the control.