Borehole survey system using Fiber Optic Gyroscopes Strapdown Incrtial Navigation

摘要

This paper will present a Fiber Optic Gyroscopes Strap down Inertial Navigation System (SINS) used in borehole survey systems. This system can be used for Wire-Line logging operations because of Fiber Optic Gyroscope's excellent capabilities of long life time, ruggedness, compactness, low cost and high environmental insensitivity. This borehole survey system utilizes the cable length signal aiding Fiber Optic Gyroscopes Strapdown Inertial Navigation System. Furthermore, this system utilizes an optimal estimation procedure based on Kalman filtering method to estimate and compensate the system errors on-line. This paper also presents a cable length model to correct the cable length signal. Simulation results show that the methods can effectively enhance the precision of the borehole survey system. In this system, the borehole survey system can fleetly and continuously survey the borehole during Wire-Line logging operations for determining the precise path of the borehole. Moreover, due to the compact frame of IMU, the borehole surveying system can be used for determining the small diameter boreholes.