Anti-swing control for 2-D under-actuated cranes with load hoisting/lowering: A coupling-based approach

Area of Science:

• Robotics and Control Systems
• Mechanical Engineering

Background:

• Under-actuated cranes present challenges in precise control due to inherent system dynamics.
• Existing anti-swing control methods often rely on simplifications like linearization or fixed rope lengths.

Purpose of the Study:

• To develop a robust anti-swing control strategy for 2D under-actuated cranes.
• To achieve simultaneous precise trolley positioning, accurate load hoisting/lowering, and effective swing suppression.
• To relax common simplifying assumptions in crane control models.

Main Methods:

• A coupling-based control approach is proposed.
• A novel composite signal is introduced to enhance coupling between actuated and under-actuated variables.
• The controller is designed using the composite signal and its derivatives, avoiding linearization of the nonlinear crane model.

Main Results:

• The proposed controller demonstrates precise trolley positioning and accurate load hoisting/lowering.
• Efficient suppression of load swing is achieved.
• Numerical simulations validate the controller's feasibility and effectiveness under relaxed model assumptions.

Conclusions:

• The developed coupling-based anti-swing control is effective for 2D under-actuated cranes.
• The novel composite signal approach offers improved performance and broader applicability compared to existing methods.
• The controller successfully addresses challenges associated with nonlinear dynamics and variable rope lengths.