Development of a piezoelectric multi-axis stage based on stick-and-clamping actuation technology

This paper presents the design, analysis and fabrication of a piezoelectric multi-axis stage based on a new stick-and-clamping actuation technology for miniaturized machine tool systems, referred to as meso-scale machine tool (mMT) systems. In the stick-and-clamping actuation system, shearing/expanding piezoelectric actuators, an inertial mass and an advanced preload system are configured innovatively to generate the motion of an inertial mass. There are two operating modes in the stick-and-clamping actuation technology: (1)stick mode and (2)clamp mode. In stick mode, the 'slow' deformation of the shearing piezoelectric actuators drives an inertial mass, which is located on the tips of the shearing piezoelectric actuators, by means of the friction force at their contact interface. On the other hand, in clamp mode, the expanding piezoelectric actuators provide the clamping force to an inertial mass when the rapid backward deformation of the shearing piezoelectric actuators occurs. The stick-and-clamping actuation technology also enables two-degrees-of-freedom (DOF) motion of an inertial mass in a single plane by perpendicularly stacking two shearing piezoelectric actuators. The 2-DOF piezoelectric multi-axis stage is developed on the basis of the stick-and-clamping actuation technology, and the dynamic and static performance analyses are conducted. The LuGre friction model for the contact interfaces is introduced, and their dynamic behaviours are characterized. In the open-loop static performance test, linear, diagonal and circular motions of the developed piezoelectric multi-axis stage are generated, and their performances are evaluated. The dynamic characteristics and static performances of the developed 2-DOF piezoelectric multi-axis stage show its applicability and effectiveness for the precision positioning system.