Development of a magnetic levitation vibration isolator using inclined permanent magnet springs

Abstract

Vibration isolation systems incorporating linear mechanical springs exhibit the undesirable characteristic of changing resonance frequency with changing payload mass. Previous research at the University of Adelaide and elsewhere has demonstrated the theoretical feasibility of vibration isolation devices utilising magnetic springs as a means of achieving a constant resonance frequency across a range of payload masses due to their nonlinear force-displacement relationship. A conceptual prototype design is presented for a levitating magnet vibration isolation device which aims to achieve a load-independent resonance frequency across a range of payload masses via the use of inclined magnetic springs. Quasi-static and dynamic system models which informed the design process are presented, as well as a finite-element model aimed at validating the assumptions of the quasi-static system model for a select set of system states. Challenges related to the conflicting design requirements of stability, low transmissibility and load-independent resonance frequency are addressed, and an experimental framework for testing the real prototype is outlined.