Application Cases

Experiment Name: Testing Application of High-Frequency Voltage Amplifier in Three-Dimensional Ultrasonic Elliptical Vibration Platform

Research Direction: Three-Dimensional Ultrasonic Elliptical Vibration

Testing Equipment: ATA-2082 High-Voltage Amplifier, Piezoelectric Ceramic Patches, Piezoelectric Stack, Capacitive Sensor Probe, Vibrometer, Data Acquisition Card

Experimental Content:
A non-resonant three-dimensional elliptical vibration-assisted machining platform was designed with resonance frequency as a constraint, achieving adjustability of vibration parameters such as frequency, amplitude, and phase. A displacement amplification mechanism was designed targeting the working stroke. Based on this displacement amplification mechanism, a large-stroke decoupled micro-positioning platform was developed. Theoretical modeling and numerical simulation methods were employed to analyze the static and dynamic characteristics of the micro-positioning platform. Finally, the positioning accuracy of the designed vibration platform and micro-positioning platform was verified through performance testing.

Figure: Vibration Platform Performance Test Setup

Experimental Procedure:
The prototype of the vibration platform is shown in Figure 1. The flexible mechanism part of the prototype was manufactured using wire electrical discharge machining (WEDM) with slow-speed wire feeding. The performance test setup and system schematic diagram for the vibration platform are shown in the figures, respectively. The x, y, and z directions of the vibration platform are each driven by a single-layer piezoelectric ceramic patch. A dual-channel voltage amplifier provides the high-frequency voltage required to drive the ceramic patches. The amplifier can generate a voltage range of -400 V to 400 V, with a maximum output frequency of 150 kHz (-3 dB).

Figure: Schematic Diagram of the Vibration Platform Performance Test System

A vibrometer was used to detect the vibration signals of the platform. The output displacement of the device was measured during one-dimensional and two-dimensional vibrations of the platform. The maximum measurement frequency of the vibrometer reaches 2.5 MHz, and the displacement resolution accuracy can reach 50 fm. The voltage signal output by the vibrometer was collected via a data acquisition card with a sampling rate of up to 1.25 MS/s.

First, a sinusoidal signal with a frequency varying from 500 Hz to 50 kHz was generated by a signal generator and applied to the piezoelectric ceramic patch through the ATA-2082 voltage amplifier. Subsequently, the output displacement of the drive axis of the piezoelectric ceramic patch was collected using the data acquisition card. Finally, based on MATLAB software, a Fourier transform was performed on the output displacement data to obtain the resonance frequency curve of the drive axis of the piezoelectric ceramic patch.

Experimental Results:

Figure: Experimental Test Results

The test results are shown in the figure. The first-order natural frequencies of the x, y, and z axes are approximately 33.69 kHz, 33.75 kHz, and 34.09 kHz, respectively, all lower than the theoretical calculations and finite element simulation results. The primary reason is the addition of a spacer (aluminum plate) mass onto the three-dimensional elliptical vibration processing platform, which increases the equivalent mass of the vibration platform. Secondly, the overall assembly of the vibration platform leads to an increase in overall mass, resulting in a decrease in its frequency. However, the measured natural frequencies of each axis of the vibration platform are still significantly higher than the operating frequencies required in practice, thus meeting the processing requirements.

Figure: ATA-2082 High-Voltage Amplifier Specifications and Parameters