An extended hysteresis observer-based adaptive robust control method for nonlinear macro-micro motion system.

Area of Science:

• Robotics and Control Systems
• Materials Science (Piezoelectric Materials)
• Mechanical Engineering

Background:

• Macro-micro composite motion platforms exhibit complex dynamics due to piezoelectric hysteresis.
• Accurate control of these systems is challenging due to inherent nonlinearities and parameter uncertainties.
• Existing control methods often struggle with precise tracking and stability in the presence of hysteresis.

Purpose of the Study:

• To propose a novel finite-time adaptive robust control (TARC) method for macro-micro composite motion platforms.
• To address and compensate for piezoelectric hysteresis nonlinearities.
• To improve tracking accuracy and system stability.

Main Methods:

• Construction of the dynamic model for the macro-micro composite motion system.
• Design of an extended hysteresis observer to estimate system states (displacement and speed).
• Development of an adaptive robust control law to mitigate uncertainties in hysteresis model parameters.

Main Results:

• The proposed TARC method achieves exponential convergence, ensuring finite-time stability.
• The control method demonstrates reduced computational load for gain adjustment by setting the system's bandwidth.
• Simulations show superior performance compared to other methods, with more stable tracking and reduced errors.

Conclusions:

• The finite-time adaptive robust control method effectively compensates for piezoelectric hysteresis in macro-micro motion platforms.
• The proposed observer-based control strategy enhances system robustness and tracking precision.
• This approach offers a computationally efficient and stable solution for advanced motion control applications.