Precision Motion Control of a Piezoelectric Actuator via a Modified Preisach Hysteresis Model and...

Area of Science:

• Nanotechnology
• Control Systems Engineering
• Materials Science

Background:

• Nonlinear hysteresis in piezoelectric nanopositioning systems degrades accuracy and control.
• Classical Preisach models struggle with rate-dependent hysteresis, limiting piezoelectric actuator performance.

Purpose of the Study:

• To improve rate-dependent hysteresis modeling in piezoelectric nanopositioning systems.
• To enhance motion control accuracy and tracking performance.
• To develop a robust control strategy for piezoelectric actuators.

Main Methods:

• Improved Preisach model using least-squares support vector machines (LSSVMs) for rate-dependent hysteresis.
• Design of an inverse Preisach model for hysteresis nonlinearity compensation.
• Implementation of a two-degree-of-freedom (2-DOF) H-infinity feedback controller for robust tracking.

Main Results:

• Significantly improved hysteresis modeling accuracy with an average RMSE of 0.0107 μm.
• Enhanced tracking performance with an average RMSE of 0.0212 μm.
• Demonstrated superior generalization and precision compared to existing methods.

Conclusions:

• The proposed LSSVM-enhanced Preisach model and 2-DOF H-infinity controller effectively address rate-dependent hysteresis in nanopositioning.
• The methodology offers a robust and precise solution for piezoelectric actuator control.
• This approach leads to substantial improvements in both modeling accuracy and system performance.