Advanced Fiber-Optic Gyroscope for Measurement-While-Drilling in Harsh Downhole Environments

New methods and technologies are needed to evaluate, improve, and/or optimize the reliability, accuracy, and/or performance of drilling technologies and instrumentation, testing methods and applications, and modeling or analysis of deep borehole systems. These new technologies will address key issues that affect the future of nuclear energy, in particular, resolution of materials disposition associated with the back-end of the nuclear fuel cycle. Disposition of defense program high-level nuclear waste products and used nuclear fuel from civilian reactors remains a significant national challenge. General statement of how this problem is being addressed IFOS’ innovation in Phase I is a novel fiber-optic gyroscope (FOG) used as a navigation/ inspection sensor in deep borehole drilling operations for measurement while drilling (MWD). The proposed sensor provides real-time, high-speed monitoring of the orientation of the drill head at the bottom of the well without the durability and reliability issues associated with the existing mechanical gyros. IFOS’ innovative solution addresses the primary challenges in this application including the harsh environment (high temperature and vibration), and size constraints including developing an unprecedented technology for a ruggedized, high-temperature optical source. In Phase I, IFOS will demonstrate the feasibility of its solution by developing a robust, small footprint, high-temperature, self-contained (downhole optics and electronics) FOG system. In Phase II the IFOS research team will install the complete sensing system in a test rig provided by IFOS collaborators and demonstrate its cost-effective, reliable, and accurate operation. Commercial Applications and Other Benefits MWD is a growing segment of the oil and gas service industry both in the US and abroad. Gyroscopes have been widely used in directional survey. The accuracy and thoroughness of MWD data have been extremely valuable in challenging oil and gas well drilling operations. In exploratory wells, real-time decisions can be made based on the MWD data regarding the control and progress of the drilling process. The public benefit is that at the conclusion of this program we will have a better, smaller gyro to offer for numerous commercial applications. A low-cost sensor meeting the desired goals would also have great impact on guidance, navigation, and control systems for launch vehicles, missiles, and other applications requiring precision stabilization. Other commercial applications include active suspension systems, large 6- DOF vibration test systems, manufacturing robotic control sensors, and commercial aircraft inertial navigation systems (INS). Key Words: fiber optic gyroscope, deep borehole deposition, directional drilling, measurement while drilling.