Dai Shichao, Yao Zhiyuan, Zhou Lifeng, He Ying
State Key Laboratory of Mechanics and Control of Mechanical Structures, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China.
Rev Sci Instrum. 2020 Dec 1;91(12):125002. doi: 10.1063/5.0023300.
A compact slider for linear ultrasonic motors (LUMs) to improve the ability of LUMs for precision positioning is proposed in this article. The compact slider can avoid the effect of variable stiffness of the traditional slider on ultra-precision positioning, which consists of two pieces of ceramic with little lubricating oil on the sliding interface. Based on contact theory and lubrication theory, the contact mechanism and the lubricating state between the slider and the support plate are analyzed. Subsequently, a dynamic model for LUMs considering the lubricating state and the ultrasonic vibration condition is obtained. Furthermore, the output speed and output force of the motor are analyzed under the influence of film lubrication. Moreover, some experiments are designed to test the feasibility and effectiveness of the compact slider for precision positioning. The results indicate that the compact slider is more effective in inhibiting the fluctuation of the output speed compared to the traditional slider, and it can improve the displacement resolution of LUMs up to 7 nm.
