Design and Algorithm Verification of a Gyroscope-Based Inertial Navigation System for Small-Diameter Spaces in Multilateral Horizontal Drilling Applications

Abstract

Abstract:In the recent years horizontal drilling (HD) has become increasingly important in oil and gas exploration because it can increase the production per well and can effectively rework old and marginal vertical wells. The key element of successful HD is accurate navigation of the drill bit with advanced measurement-while-drilling (MWD) tools. The size of the MWD tools is not significantly restricted in vertical wells because there is enough space for their installation in traditional well drilling, but the diameter of devices for HD must be restricted to less than 30 mm for some applications, such as lateral drilling from existing horizontal wells. Therefore, it is essential to design miniature devices for lateral HD applications. Additionally, magnetometers in traditional MWD devices are easily susceptible to complex downhole interferences, and gyroscopes have been previously suggested as the best avenue to replace magnetometers for azimuth measurements. The aim of this paper is to propose a miniature gyroscope-based MWD system which is referred to as miniature gyroscope-based while drilling (MGWD) system. A prototype of such MGWD system is proposed. The device consists of a two-axis gyroscope and a three-axis accelerometer. Miniaturization design approaches for MGWD are proposed. In addition, MGWD data collection software is designed to provide real-time data display and navigation algorithm verification. A fourth-order autoregressive (AR) model is introduced for stochastic noise modeling of the gyroscope and the accelerometer data. Zero velocity and position are injected into a Kalman filter as a system reference to update system states, which can effectively improve the state observability of the MGWD system and decrease estimation errors. Nevertheless, the azimuth of the proposed MGWD system is not observable in the Kalman filter, and reliable azimuth estimation remains a problem.

Particle Filter with Novel Nonlinear Error Model for Miniature Gyroscope-Based Measurement While Drilling Navigation

“…Azimuth MEMS sensor provides the angular rate of the drill bit along the Z-axis while the angular rate along the X-axis is obtained from the pitch MEMS sensor. For implementation of the pure INS algorithm, the angular rate along the Y-axis is evaluated by the specific force obtained from the pitch MEMS sensor [ 12 ].…”

“…The emergence of a low-cost, small-size, and high-performance MEMS sensor brings the gyroscopes to the small-diameter RMHWD. The MGWD device with two-axis gyroscopes and three-axis accelerometers in the application of small-diameter space (less than 24 millimeters) was proposed in [ 12 ], in which the angular rate (Y-axis) of MGWD tools is calculated by the accelerometers in the horizontal plane when the drilling equipment is under quasi-stationary conditions. The MGWD system can provide high-precision navigation solutions in short-term [ 13 ] and can perform real-time data transmission between the MGWD tools and the ground operation center.…”

Research on the Strategy of Motion Constraint-Aided ZUPT for the SINS Positioning System of a Shearer

“…However, a major problem with this kind of solution is that the estimation error grows with time, due to the typical drift of the inertial measurement, because of the poor working conditions for the shearer in the coal mine. Since the measured accuracies of the accelerometer and gyroscope in the SINS are limited by the high cost of the sensors, the measured error of the SINS will cause the accumulative error in the calculation process of the orientation and position [ 10 ]. Hence, the positioning accuracy of the SINS for the shearer will be significantly influenced.…”