Sensor fault detection and minimum detectable fault analysis for dynamic point-the-bit rotary steerable system.

Area of Science:

• Engineering
• Control Systems
• Robotics

Background:

• Dynamic Point-the-Bit Rotary Steerable Systems (DPRSS) are crucial in directional drilling.
• Sensor faults can compromise system performance and safety.
• Drilling disturbances introduce significant challenges to fault detection.

Purpose of the Study:

• To develop a robust sensor fault detection method for DPRSS.
• To address the complexities introduced by drilling disturbances.
• To ensure reliable operation and safety of rotary steerable systems.

Main Methods:

• Modeling the DPRSS as a linear system with disturbances (unknown inputs, noise, model perturbations).
• Designing a finite-frequency zonotopic fault detection observer.
• Utilizing finite-frequency range H-performance and P-radius criterion for observer gain design.

Main Results:

• The proposed observer effectively detects sensor faults.
• The method demonstrates robustness against drilling disturbances.
• A calculation for minimum detectable faults was established.

Conclusions:

• The developed fault detection observer is effective for DPRSS.
• The approach successfully balances fault sensitivity and disturbance robustness.
• Simulations and experiments validate the proposed methodology.