Abstract
The instability of kinematic pairs made with permanent magnets (passive magnetism) significantly restricts their technical use. On the other hand, they show very good tribological properties: null friction and wear. In previous works, it has been verified that by using Mathieu Functions any instability of the levitated member may be removed if one of the two members is subjected to a parametric excitation. In this paper, the problem is discussed directly utilizing the nonlinear equation of motion of the levitated member, and it is confirmed that it may be stable.
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