Time-Synchronized Convergence Control for n-DOF Robotic Manipulators with System Uncertainties

Area of Science:

• Robotics
• Control Systems Engineering
• Mechatronics

Background:

• Robotic manipulator control often faces challenges with simultaneous convergence of system states.
• Existing finite-time control methods may not guarantee synchronized convergence.
• Uncertainties and disturbances can hinder precise robotic system performance.

Purpose of the Study:

• To propose a novel time-synchronized (TS) convergence control method for robotic manipulators.
• To ensure simultaneous convergence of all system states to an equilibrium point in finite time.
• To enhance the robustness and precision of robotic systems under uncertainties.

Main Methods:

• Introduction of a time-synchronization convergence concept based on the ratio persistence property.
• Development of a robust disturbance observer compatible with the TS control framework.
• Design of a finite time-synchronized controller for robotic manipulators.
• Stability analysis to validate the proposed TS control method.

Main Results:

• The proposed TS control method ensures simultaneous convergence of all robotic manipulator states.
• The robust disturbance observer accurately estimates system uncertainties.
• Stability analysis confirms the feasibility and effectiveness of the TS control approach.
• Simulations with a two-link rehabilitation robotic system show superior performance compared to existing methods.

Conclusions:

• The developed time-synchronized control method offers a robust solution for simultaneous state convergence in robotic manipulators.
• The integration of a disturbance observer enhances the system's ability to handle uncertainties.
• The TS control strategy demonstrates significant advantages, particularly for applications like rehabilitation robotics.