Piezoelectric active bearings and supports: structures, characteristics and applications

This paper presents new concepts of piezoelectric active bearings and supports used for precise positioning and covers results of the latest developments of the devices with active bearings and supports. Several applications of the single-degree-of-freedom and multi-degree-of-freedom devices are presented where piezoelectric active bearings or supports are used. All introduced piezoelectric devices can be characterized by different accuracy, resolution and the time response. Important feature of the proposed piezoelectric active bearings and supports is that they have zero processing datum surface errors therefore can be used for precise measuring and manufacturing systems. Dynamic models of the oscillation transformation of the stator into controlled rotation of the positioning object or rotor is described and results of numerical modelling are presented.