Ultra-thin flattened piezoelectric drivers for aerospace filter wheel

With the advantages of thin structure, high efficiency, and high resolution, the in-plane thin-plate ultrasonic motors have been commercially produced and used in advanced applications, especially low-voltage driving for smart devices and precision positioning in aerospace services. The filter wheel mechanism is complex because of the stacked and heavy transmission system and additional electronic control modules, which hinder online detection efficiency and the development of miniaturized detection technology in aerospace. An in-plane linear ultrasonic motor prototype was developed using a longitudinal-bending hybrid vibration of the thin plate with the arranged grooves for flexibilization. The elliptical moving locus of the double driving feet was analyzed, and the working principle of this motor was presented. A flexible stator was optimized using the finite element method, considering the frequency degeneracy of longitudinal and bending vibrations. Meanwhile, the output performance of the piezoelectric motor was experimentally investigated. Results show that the proposed motor can work in a wide range of working conditions from 75V_pp to 350 V_pp. The forward (to the right) and backward (to the left) speeds under the no-load condition get to 0.25m/s and 0.22 m/s, respectively; the maximum thrust is 3.4 N at the exciting voltage of [email protected], and the thrust-to-weight ratio reaches 47 (the stator weight is 7.36 g). Under the low voltage driving of 75V_pp@45.7kHz, the proposed motor can get a thrust of 0.5 N and a no-load speed of 80 mm/s. Compared with the in-plane linear ultrasonic motor without grooves, the amplitude of the driving foot for the proposed motor with grooves increases. After the stabilization of the stator, the motor's no-load speed increases by 51.5 %, and the maximum thrust force increases by 36 %. This study is conducive to the miniaturization, lightweight design, and manufacturing thin-plate motors for aerospace services. © 2025 Elsevier Ltd.