A novel impact two-degree-of-freedom (2-DOF) motor based on the decomposed screw-type motion of a piezoelectric actuator (PA) has been proposed. The fabricated prototype motor has a maximum diameter of 15 mm and a length of 100 mm which can produce a maximum torsional angle of about 1000 μrad and a maximum longitudinal displacement of about 1.03 μm under a saw-shaped driving voltage with 720 Vp-p (peak-to-peak driving voltage). When the axial prepressure generated by the spring is about 1N and the radial prepressure generated by the snap ring is about 14 N, the fabricated motor realizes rotary motion with the driving frequency from 200 Hz to 4 kHz. When the axial prepressure generated by the spring is about 11.7 N and the radial prepressure generated by the snap ring is about 21.1 N, the fabricated motor realizes linear motion with the driving frequency from 2 kHz to 11 kHz. In the experiments, the prototype motor can achieve 9.9 × 105 μrad/s rotary velocity at 2 kHz and it can achieve 2.4 mm/s linear velocity at 11 kHz under the driving voltage of 720 Vp-p.
Two-degree-of-freedom Control of a Piezoelectric Actuator with Hysteresis Compensation
