Event-based adaptive tracking control for robotic systems with deferred position constraints and unknown...

Area of Science:

• Robotics and Control Systems

Background:

• Robotic systems often face challenges like unknown backlash-like hysteresis (BLH) and deferred position constraints, complicating precise tracking control.
• Conventional barrier Lyapunov function methods rely on assumptions that limit their applicability to systems with position constraints.

Purpose of the Study:

• To propose an event-based adaptive tracking control scheme for n-link robotic systems.
• To address unknown BLH and deferred position constraints without violating pre-specified time constraints.
• To remove common assumption conditions found in traditional barrier Lyapunov function methods.

Main Methods:

• A transformation error combined with an asymmetric Lyapunov function is utilized for control design.
• A Nussbaum function is employed to counteract the effects of unknown BLH.
• An event-triggered mechanism is implemented to optimize network bandwidth usage.
• Lyapunov theory forms the basis for ensuring signal boundedness.

Main Results:

• The proposed control tactic ensures that position constraints are not violated after a user-pre-specified time.
• The adverse effects of unknown BLH are effectively offset.
• The event-triggered mechanism conserves network bandwidth resources.
• All signals of the robotic systems are demonstrated to be bounded under the specified conditions.

Conclusions:

• The developed event-based adaptive tracking control scheme is effective for n-link robotic systems with unknown BLH and deferred position constraints.
• The method offers improved robustness and efficiency by conserving network resources and removing restrictive assumptions.