Fault-tolerant scheme for robotic manipulator-Nonlinear robust back-stepping control with friction compensation
Khurram Ali1, Adeel Mehmood1, Jamshed Iqbal2
1Department of Electrical and Computer Engineering, COMSATS University Islamabad, Pakistan.
Plos One
|August 20, 2021
Summary
This study introduces a fault-tolerant control (FTC) system for robot manipulators, enhancing reliability by using an observer and hardware redundancy to manage actuator and sensor failures. The approach ensures stable robot operation despite faults and friction.
Area of Science:
- Robotics
- Control Systems Engineering
- Mechatronics
Background:
- Autonomous robots require high stability and reliability, making component failure unacceptable.
- Identifying and counteracting faults is crucial for operational success in mechatronics.
Purpose of the Study:
- To propose a novel Fault-Tolerant Control (FTC) strategy for robot manipulators.
- To enhance robot performance and efficiency in the presence of actuator and sensor faults.
Main Methods:
- A hybrid control scheme combining an observer and hardware redundancy.
- Development of a dynamic LuGre friction model for a five Degree of Freedom (DoF) robot manipulator.
- Adaptive back-stepping methodology for fault estimation and controller reconfiguration.
Main Results:
- Effective fault detection by comparing actual and observed states.
- Successful fault tolerance using redundant sensors.
- Demonstrated robustness against friction and component faults.
Conclusions:
- The proposed FTC strategy is effective, even with model-based friction compensation.
- The approach significantly improves tracking performance and robustness.
- Validates the efficiency of the proposed control for reliable robotic systems.
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