Fuzzy sliding mode control of piezo-driven stage

Area of Science:

• Mechanical Engineering
• Control Systems Engineering
• Nanotechnology

Background:

• Precision motion stages are crucial for nanotechnology and advanced manufacturing.
• Piezoelectric actuators offer high resolution but suffer from hysteresis, limiting positioning accuracy.
• Existing control methods struggle to fully compensate for PZT hysteresis.

Purpose of the Study:

• To develop an effective control strategy to mitigate hysteresis in piezoelectric actuators for nanometer-level positioning.
• To analyze the mechanical characteristics and dynamic behavior of a flexible-hinge-based motion stage.
• To validate the performance of the proposed control method through experimental verification.

Main Methods:

• Finite element analysis (FEA) was used to determine the natural frequency and modal characteristics of the motion stage.
• The Bouc-Wen hysteresis model was employed, with parameters identified using particle swarm optimization (PSO).
• A proportional-integral-differential (PID)-type fuzzy sliding mode control (FSMC) was designed, incorporating fuzzy logic for adaptive control.

Main Results:

• The study successfully identified model parameters for the Bouc-Wen hysteresis model using PSO.
• A novel FSMC strategy was designed to address PZT hysteresis as a disturbance.
• Experimental results demonstrated the effectiveness of the FSMC in improving the positioning accuracy of the piezo-driven stage.

Conclusions:

• The proposed FSMC effectively compensates for piezoelectric actuator hysteresis, enabling nanometer-level precision positioning.
• The integration of fuzzy logic with sliding mode control offers a robust solution for complex control challenges in precision motion systems.
• This research contributes to the advancement of high-precision motion control technologies for scientific and industrial applications.