Influence of Materials on the Transportation Performance of a Self-running Actuator Based on Ultrasonic Levitation

Ultrasonic levitation (UL) technique holds promising application prospects in the field of actuators due to its oil-free operation, compact structure, and ease of control. This study explores the transportation performance capabilities of a self-running, non-contact actuator utilizing the UL principle, focusing on performance evaluation and material optimization. Initially, the distribution of vibration amplitude was determined using the Finite Element Method (FEM), facilitating the estimation of film thickness. Subsequently, governing equations pertaining to squeeze film pressure were formulated. Incorporating the film thickness and governing equations, air film pressure distribution was ascertained through the Finite Difference Method (FDM). The levitation and driving forces were then calculated based on the force analysis. Furthermore, this paper delves into the impact of the actuator's material on its transportation efficiency. Prediction results show that aluminum yields a higher driving force than titanium at the same input voltage, but titanium surpasses aluminum in generating propulsive force at equivalent amplitude levels. This investigation underscores the significance of material selection in enhancing the performance of UL-based actuators.