An ultra-precision XY/spl Theta//sub Z/ piezo-micropositioner. II. Experiment and performance

For pt I see ibid., vol. 46, no. 4 (July 1999). The performance of an ultra-precision three dimensional micropositioner using the built-in multilayer piezoelectric actuators and sensors is presented. The compact design utilizes the monolithic mechanism to achieve translation in the X- and Y-axes and rotation in the theta(Z) axis with high stiffness and high damping. Hysteresis, nonlinearity, and drift of piezoelectric effects are improved by incorporating the sensors in a feedback control. Experiments demonstrate that the micropositioner is capable of a 10 nm resolution over the travel range of 17.8 mum in the X- and Y-axes and a 0.15 murad resolution over the range of 585 murad in the theta(Z) axis. The crossaxis interferences are within 1.14% of the full range. The results agree well with predictions by theoretical models.