Abstract：A novel cylindrical magnetic levitation gravity compensator was proposed in this paper. The secondary adopted Halbach permanent magnet structure that had such excellent advantages as large levitation force and low vertical stiffness. The structure of this new-type magnetic levitation gravity compensator was introduced and its mathematical model was built. The air gap magnetic flux density from permanent magnet rings was calculated using equivalent current method. The expressions of static levitation force, dynamic levitation force and stiffness were derived. Through finite element simulation, the static characteristics of cylindrical magnetic levitation gravity compensator were obtained. And the special problems of low stiffness passive magnetic levitation were explained. Finally, a prototype was manufactured. The prototype experiment verified the feasibility of the proposed magnetic levitation gravity compensator.
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