Design and Analysis of a PWM-Controlled Variable Inertance and Variable Damping Device With Nearly Continuous Adjustment

This article proposes a pulse width modulation (PWM)-controlled variable inertance and variable damping device (VIVD) that allows for nearly continuous adjustment of the equivalent inertance and damping. A physical prototype is fabricated and tested. To decouple the inertance and damping adjustments for sinusoidal vibration systems, a prescribed-time sinusoidal frequency tracker (PTSFT) is adopted and embedded in the PWM-controlled VIVD. The feasibility of the method is demonstrated through theoretical and experimental verification. Additionally, a novel dynamic vibration absorber (DVA) is constructed using the proposed PWM-controlled VIVD with the embedded PTSFT. Hardware-in-the-loop tests are performed to demonstrate the effectiveness of the proposed DVA system.