Non-linear oscillations in a passive magnetic suspension

The paper analyzes the dynamical behavior of a single degree of freedom (SDOF) passive magnetic suspension realized coupling traditional springs with rare-earth permanent magnets. The natural frequency of the device depends weakly on the mass due to the strongly non-linear magnetic repulsive force. The system exhibits features typical of non-linear oscillators, such as jump phenomena and multivalued frequency–response curves. In fact, for appropriate combinations of the parameters, multiple steady-state solutions appear. The periodic stationary solutions and the stability properties are investigated numerically and with a semi-analytical approach. Finally, comparisons with experimental results have been reported.