Robust control design for a wheel loader using Hinfinity and feedback linearization based methods

Area of Science:

• Engineering
• Control Systems
• Robotics

Background:

• Heavy equipment industry increasingly uses electro-hydraulic control systems.
• Current design practices lack systematic methods for plant uncertainties and multi-input multi-output (MIMO) dynamics.

Purpose of the Study:

• To present two H-infinity based robust control designs for an automatic bucket leveling mechanism in a wheel loader.
• To improve stability robustness by applying feedback linearization before controller design.

Main Methods:

• Developed two H-infinity robust control designs for a wheel loader's automatic bucket leveling mechanism.
• Considered a MIMO nonlinear model of the electro-hydraulically actuated wheel loader linkage.
• Validated controller robustness through analysis and simulation using a complete nonlinear model.

Main Results:

• Controller designed for the base plant model.
• Controller designed for the plant with feedback linearization, showing improved stability robustness.
• Simulations confirmed the effectiveness of the robust control designs.

Conclusions:

• H-infinity based robust control offers a systematic approach to designing control systems for heavy equipment.
• Feedback linearization enhances stability robustness in electro-hydraulic systems.
• The presented methods effectively address plant uncertainties and MIMO dynamics in wheel loader control.