Transfer matrix model and experimental validation for a radial-torsional ultrasonic motor

The acoustofluidic actuation produced by piezoelectric transducer is capable of propelling micro underwater robots forward, yet the motion pattern is relatively simplistic. To solve this problem, a pump-jet swimmer with a combination of the underwater acoustic radiation effect is proposed in this work. The absorption and discharge of internal piezoelectric pump provide the linear forward power, and turning is achieved under the acoustic propulsive force of the external dual piezoelectric actuators. The working mode and optimal driving frequency of the piezoelectric actuators are determined through finite element simulation and mechanical vibration characteristic tests. And the key dimensional parameters of the piezoelectric pump are optimized in the light of the output flow measurements. Finally, a prototype with the size of Ф3.1 cm×12 cm is fabricated for underwater driving performance experiments, which demonstrated well functions in straight swimming, turning, and loading. The swimmer with 20 g of additional load achieves a maximum speed of 105 mm/s at the voltage of 180 Vp-p, it also completes the obstacle avoidance in water along a certain path. The rationality of this conceived actuation mechanism is preliminarily verified, which shows a potential for fixed-point transportation in the complex underwater situations.

Section: Introductionmentioning

confidence: 99%

Development of a pump-jet piezoelectric swimmer with acoustic radiation actuation

Zheng,

Liu,

Wang

et al. 2024

“…As a typical resonant piezoelectric motor, ultrasonic motor always uses high-frequency sinusoidal electrical signals to drive the stator to generate elliptical vibration at resonance point and converts the stator elliptical vibration into continuous high-speed output through friction coupling. However, the vibration amplitude of the stator in the harmonic state is relatively large and the resolution is low [8][9][10][11], which is difficult to be directly applied to high-resolution precision positioning occasions.…”

Section: Introductionmentioning

confidence: 99%

Bipedal driven inertial type piezoelectric motor working under quasi-static and resonant states

Qing

Mingfei

Han

et al. 2023

An inertia piezoelectric motor based on bipedal driven, which can work in not only quasi-static but also resonant states, is proposed, designed, fabricated and studied considering the high resolution of quasi-static piezoelectric motor and the high speed of resonant piezoelectric motor. The two stators of the piezoelectric motor are drived by two sinusoidal electrical signals with 1:2 frequency ratio to generate sinusoidal vibration on the corresponding driving foot. A continuous step motion without frequency limitation is realised under the action of inertia and friction forces after synthesising the sinusoidal vibration of different frequencies into mechanical sawtooth vibration. The natural resonant frequencies of the piezoelectric motor are adjusted to a specific proportion to combine the vibrations in the resonant state through finite element analysis. In the structure of two stators, each stator has a corresponding inertia block, and the corresponding resonant frequency can be altered by adjusting the mass of the inertial block without affecting the other resonant frequency, thus markedly simplifying the design difficulty of the piezoelectric motor which can work in quasi-static and resonant states. The motion characteristics of the prototype are tested by building the prototype and experimental platform. Experimental results show that the maximum speed of the prototype is 29.3 mm/s and the maximum load is 200 g in the resonant state, the minimum displacement resolution of prototype motor is 0.26 μm in the quasi-static state. The motion characteristics of the prototype are consistent with the theoretical analysis, which provides an effective idea to improve the comprehensive performance of the piezoelectric motor.

“…The ultrasonic motor is a typical resonant-type piezoelectric motor; the piezoelectric element inside this motor is excited at the resonant frequency corresponding to its stator, which produces a sufficient amplitude at the contact interface to drive the end effector. In most cases, resonant-type piezoelectric motors are used for macro actuation applications [28][29][30][31]. Nonresonant-type piezoelectric motors, which are commonly used as micro manipulators, deal with the accurate positioning tasks.…”

Section: Introductionmentioning

confidence: 99%

A novel three-phase excitation piezoelectric motor for macro-micro actuation: integration design, systematic modeling, and experimental evaluation

Qiu

Jin

Wang

et al. 2023

Self Cite

Macro-micro actuators require complex feedback control systems to obtain high positioning cooperativeness. However, the mechanical connections of macro-micro actuators are generally redundant in terms of their size, which is highly unfavorable for both miniaturization and integration. This paper presents an approach to address this problem based on a novel integration design for a three-phase excitation piezoelectric motor (TPM) that is capable of performing macro-micro actuation by switching its operating mode from resonant to nonresonant. The load capacity of the proposed TPM can reach 0.39 Nm with a maximum speed of 3.82 rad/s (36.5 rpm). This performance is achieved by using a unique triangular flexible stator that contains three piezoelectric stack actuators (PSAs) acting as vibrators and is excited by a three-phase electrical signal. A time-domain electromechanical coupling dynamic model is developed to determine the dynamic behavior of the proposed motor, and the modeling results are validated successfully by experimental results obtained from a fabricated prototype. The proposed motor is expected to be helpful for integration design of piezoelectric devices that require macro-micro actuation.