Finite-time anti-saturation control for Euler-Lagrange systems with actuator failures.
Bing Huang1, Sai Zhang2, Yushan He3
1Science and Technology on Underwater Vehicle Laboratory, Harbin Engineering University, Harbin 150001, China.
ISA Transactions
|September 8, 2020
Summary
This study presents two finite-time control strategies for stabilizing Euler-Lagrange systems with actuator failures. These methods ensure system states reach the origin within a finite time, offering robust fault tolerance.
Area of Science:
- Control Systems Engineering
- Robotics
- Nonlinear Dynamics
Background:
- Euler-Lagrange systems are fundamental in modeling mechanical systems.
- Actuator failures pose significant challenges to system stability and performance.
- Finite-time control offers faster convergence compared to traditional control methods.
Purpose of the Study:
- To develop novel finite-time control strategies for Euler-Lagrange systems.
- To address the challenge of actuator failures and external disturbances.
- To ensure bounded control outputs for practical implementation.
Main Methods:
- Sliding mode control combined with adaptive techniques.
- Development of two distinct control architectures.
- Utilizing properties of Euler-Lagrange systems and hyperbolic tangent functions.
Main Results:
- Finite-time stabilization of Euler-Lagrange systems demonstrated.
- The first controller requires exact fault and disturbance information.
- The second controller uses adaptive laws for unknown parameter estimation, enhancing robustness and fault tolerance.
- Boundedness of controller outputs is theoretically proven.
Conclusions:
- The proposed control strategies effectively stabilize Euler-Lagrange systems under actuator failures.
- The adaptive approach provides a practical solution for systems with unknown parameters.
- Simulation results validate the efficacy of the developed finite-time control algorithms.
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