Dynamic Vibration Absorber (DVA) Using Piecewise and Magnetic Stiffness Mechanism

Linear dynamic vibration absorberAbsorber (DVA) efficiently suppresses the structural vibration within the 3 dB amplitude frequency bandwidth. Beyond this bandwidth, it may not be able to suppress the vibration. In fact, if not properly tuned, it may increase the vibration of the structure. This study examines a DVA mechanism incorporating a unique piecewise and magneticMagnetic stiffness combination. By integrating these two types of stiffness, the DVA achieves nonlinear modes, improving its ability to dampen vibrations over a wider frequency range. The positioning of limit blocks and the gap between magnets allows precise control over the level of nonlinearity for each mode, namely, hardening, softening and combined modes. Dynamic measurements were conducted to analyze the device’s dynamic performance in the form of deflection-frequency characteristics, providing insights into the device’s response across a frequency range (10–50 Hz) for each mode. The measurement results from the three modes were compared. While hardening and softening modes proved to have the ability to widen the bandwidth, the combined mode appeared to be the most effective one in widening the bandwidth due to the decrease in the multi-stable solution frequency region.