Application Cases

【Overview】
In this study, the Aigtek ATA-2041 high-voltage amplifier was used to build an active control experimental setup for a flexible cantilever beam actuated by a piezoelectric MFC actuator, providing experimental support for wideband high-precision nonlinear control of the MFC actuation system.

Experiment Name: Wideband Linearization Control of a Flexible Cantilever Beam Actuated by a Piezoelectric MFC Actuator Based on an EMD Integrated Model

Experiment Objective:
To verify whether feedforward and composite linearization control methods based on the MPI model can effectively reduce the influence of low-frequency hysteresis characteristics of the piezoelectric MFC actuator on the output displacement accuracy of the flexible cantilever beam, and to verify whether feedforward and composite linearization control methods based on the EMD integrated model can compensate for the combined effects of hysteresis, creep, and structural dynamics over a wide frequency range. By comparing the effects of feedforward and composite control in these two methods, the goal is to linearize the wideband input-output relationship of the flexible cantilever beam, improve its output displacement accuracy, and provide experimental support for wideband high-precision nonlinear control of the piezoelectric MFC actuator system.

Testing Equipment:
ATA-2041 high-voltage amplifier, flexible cantilever beam actuated by a piezoelectric MFC actuator, computer, vibrometer controller, real-time simulation system, vibrometer optical head.

Experimental Procedure:
An active control experimental setup for a flexible cantilever beam actuated by a piezoelectric MFC actuator was built. First, the MPI model-based feedforward and composite linearization controllers were designed using the MPSO algorithm. Their compensation effects on hysteresis were tested and verified under low-frequency drive signals. Next, a control method based on the EMD integrated model was established. The dynamic mechanical model was reduced to a fourth-order model, and a pseudo-inverse model was constructed. PI feedback parameters were tuned, and tests were conducted under wideband (5–30 Hz) harmonic signals. The hysteresis curves and linearization errors of uncontrolled, feedforward, and composite control were compared to verify the effectiveness of both control methods under low-frequency and wideband conditions.

Figure 1: System Control Block Diagram

Figure 2: Experimental Platform

Experimental Results:

1. Both the MPI model-based feedforward and composite linearization controls effectively reduced the influence of the low-frequency hysteresis characteristics of the piezoelectric MFC actuator on the output displacement accuracy of the flexible cantilever beam, with composite control achieving superior nonlinearity reduction.

2. The EMD integrated model-based feedforward and composite linearization controls effectively compensated for the combined effects of hysteresis, creep, and structural dynamics over a wide frequency range, achieving linearization of the wideband input-output relationship of the flexible cantilever beam.

3. Compared to feedforward control, the EMD integrated model-based composite control reduced nonlinearity by a maximum of 50.69% and a minimum of 22.19% under different drive voltage frequencies, demonstrating superior wideband linearization control accuracy.

4. After reducing the dynamic mechanical model of the flexible cantilever beam from seventh order to fourth order, it remained in good agreement with experimental data in terms of amplitude-frequency and phase-frequency responses, proving stable for wideband linearization control.

5. The introduction of a feedback loop effectively eliminated bias errors caused by model inaccuracies and external disturbances in feedforward control. However, at higher drive voltage frequencies, the real-time performance of feedback control had a certain impact on control accuracy.

   
   

Figure 3: Frequency Response Comparison Curves of the Seventh-Order System, Fourth-Order System, and Experimental Data

Advantages of Aigtek Amplifiers in This Application:

1. High voltage output capability – Provides the high-intensity drive electric field required for MFC actuator actuation.

2. Wide bandwidth and high slew rate – Accurately reproduces wideband harmonic signals, ensuring the accuracy of dynamic mechanical model validation.

3. Low distortion and high output stability – Ensures the purity and repeatability of excitation conditions in feedforward and composite control comparison experiments.

Recommended Product: ATA-2041 High-Voltage Amplifier

Figure: ATA-2041 High-Voltage Amplifier Specifications and Parameters

The experimental materials in this article are compiled and released by Xi'an Aigtek Electronics. Aigtek has become a large-scale instrument and equipment supplier with a wide range of products in the industry. Demo units are available for free trial. Xi'an Aigtek Electronics is a high-tech enterprise specializing in the research, development, production, and sales of electronic testing instruments such as power amplifiers, high-voltage amplifiers, power signal sources, preamplifiers for weak signals, high-precision voltage sources, and high-precision current sources.