Sliding mode control with self-tuning law for uncertain nonlinear systems
Tzu-Chun Kuo1, Ying-Jeh Huang, Shin-Hung Chang
1Department of Electrical Engineering, Ching Yun University, Taiwan.
ISA Transactions
|December 7, 2007
Summary
A novel robust sliding mode control method with self-tuning capabilities effectively minimizes tracking errors in nonlinear systems with uncertain parameters. This approach ensures system stability and has been validated through simulations and experiments.
Area of Science:
- Control Engineering
- Nonlinear Systems Analysis
- Robotics
Background:
- Nonlinear systems with uncertain parameters pose significant challenges for traditional control strategies.
- Achieving robust and stable control performance is crucial for practical applications.
Purpose of the Study:
- To propose a robust sliding mode control (SMC) strategy with a self-tuning law for nonlinear systems.
- To address parameter uncertainties and ensure precise tracking performance.
Main Methods:
- Developed a self-tuning law to adjust control gains and a bipolar sigmoid function online.
- Utilized Lyapunov stability analysis to guarantee system stability.
- Applied the control strategy to a planetary gear type inverted pendulum system.
Main Results:
- The proposed self-tuning SMC effectively reduced tracking errors to near zero.
- Online tuning of control parameters demonstrated adaptability to system uncertainties.
- Both simulation and experimental results confirmed the control approach's effectiveness.
Conclusions:
- The developed robust sliding mode control with self-tuning law offers a reliable solution for controlling nonlinear systems with uncertainties.
- The method provides enhanced tracking performance and guaranteed stability.
- Validated effectiveness in a complex mechanical system (inverted pendulum).
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