Fixed-time fault-tolerant control for electro-mechanical braking systems under input saturation and time-delay

Area of Science:

• Automotive Engineering
• Control Systems Theory
• Mechatronics

Background:

• Electro-mechanical brakes (EMB) are crucial for modern vehicle safety systems.
• Existing systems face challenges with faults, saturation, and time delays.
• High-precision fault-tolerant anti-lock braking systems (ABS) require advanced control strategies.

Purpose of the Study:

• To propose a novel fault-tolerant control strategy for EMB systems.
• To enhance vehicle safety and braking performance under various fault conditions.
• To ensure optimal slip ratio maintenance for maximum braking efficiency.

Main Methods:

• Implementation of a fixed-time controller with time-varying funnel constraints.
• Introduction of a fixed-time command filter to address derivative explosion.
• Development of a fractional-order compensation strategy for saturation and inaccuracies.
• Integration of fixed-time extended state observers (FESO) for disturbance rejection.

Main Results:

• The proposed strategy effectively maintains the slip ratio within the optimal range.
• Demonstrated robustness against external disturbances, supply faults, and input delays.
• Achieved global fixed-time stability of the closed-loop system.
• Validated effectiveness across dry, wet, and snowy road conditions via simulations.

Conclusions:

• The novel fault-tolerant control strategy enhances EMB system safety and performance.
• The system exhibits significant robustness and fault tolerance.
• The approach is suitable for high-precision fault-tolerant ABS development.