Gyrocompassing Survey Tool Rotation Compensation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Gyrocompassing survey tools used in wellbore drilling often fail to remain perfectly stationary, leading to errors in orientation measurements due to residual tool rotation, which affects the accuracy of azimuth calculations.
Innovation Solution
Incorporating both accelerometer and gyroscopic sensors to monitor and compensate for tool rotation by calculating the tool face rate of change and subtracting it from the total rotation rate, ensuring accurate orientation measurements during gyrocompassing surveys.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If the survey tool remains stationary during gyrocompassing survey, then the orientation measurement accuracy is improved, but the tool rotation cannot be fully eliminated in high-inclination wellbores
Solution Approach 1:
The system continuously monitors tool rotation using rate gyroscopes and calculates tool face rate of change using accelerometers. This feedback information is used to compensate for residual tool rotation during gyrocompassing surveys, allowing the system to maintain measurement accuracy even when the tool is not perfectly stationary.
Solution Approach 2:
The patent replaces the mechanical requirement of perfect tool stationarity with a computational solution. By using sensor data from rate gyroscopes and accelerometers along with mathematical calculations, the system substitutes the mechanical constraint with an electronic/computational compensation mechanism that achieves the same goal of accurate orientation measurement.
2Measurement precision
If both accelerometer and gyroscopic sensors are used to monitor and compensate for tool rotation, then the azimuth calculation accuracy is improved, but the device complexity increases
Solution Approach 1:
The system uses rate gyroscopes that serve dual purposes: they provide the primary orientation data for gyrocompassing surveys and simultaneously detect tool rotation that needs to be compensated. This multi-functionality reduces the need for separate dedicated sensors for each measurement task, thereby limiting the increase in device complexity.
Solution Approach 2:
The patent combines the data from accelerometer modules and gyroscopic sensor modules into a unified compensation calculation. By merging these sensor inputs and processing them together through a single compensation algorithm, the system achieves accurate azimuth calculation without requiring entirely separate independent systems for each function.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach significantly reduces errors in azimuth calculations, improving the accuracy of survey data by accounting for tool rotation, even in high-inclination wellbores, and maintaining measurement precision over varying environmental conditions.
Implementation Method 1
The rate gyroscope undergoes precession as a consequence of the Earth's rotation. The rate gyroscope is configured to detect the components of this precession and to generate at least one corresponding data signal indicative of the orientation of the rate gyroscope's spin axis relative to the Earth's axis of rotation.
Implementation Method 2
receiving a first plurality of signals from at least one accelerometer module of the survey tool. The first plurality of signals is indicative of measurements of the Earth's gravitation vector taken by the at least one accelerometer module during the gyrocompassing survey measurement.
Data Source
Figure 1
Figure 2
Figure 3A
AI summary
Systems and methods for monitoring the tool rotation of a survey tool 320 within a wellbore 312 during a gyrocompassing survey measurement are provided. A plurality of signals from at least one accelerometer module 330 of the survey tool 320 is indicative of measurements of the Earth's gravitation vector taken by the at least one accelerometer module 330 during the gyrocompassing survey measurement. The plurality of signals is used to calculate a tool face rate of change of the survey tool with respect to the wellbore during the gyrocompassing survey measurement.