Smart data acquisition for gyrocompass applications
AssigneeSchlumberger Technology Corporation
InventorsArnaud Jarrot, Makito Katayama, Arnaud Croux, Joffroy Urbain
Life of this patent
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Abstract
A method for making gyroscopic azimuth measurements includes estimating a pitch angle and a roll angle of a gyroscopic surveying tool in a wellbore; determining a measurement duration for each of a plurality of gyroscope measurements from the estimated pitch and roll angles; making each of the plurality of gyroscope measurements at the determined measurement duration when the gyroscope is disposed at a corresponding plurality of rotational positions in the tool housing; and computing an azimuth of the wellbore from the plurality of gyroscope measurements.
Claims20
A method for surveying a wellbore, the method comprising:
- deploying a gyroscopic surveying tool in the wellbore, the gyroscopic surveying tool including at least one gyroscope disposed to rotate in and with respect to a tool housing, wherein the gyroscopic surveying tool includes a micro electro mechanical systems (MEMS) gyroscope;
- determining a pitch angle and a roll angle of the gyroscopic surveying tool in the wellbore;
- determining, using the pitch angle and the roll angle, a plurality of measurement durations, each measurement duration of the plurality of measurement durations associated with an associated gyroscope measurement of a plurality of gyroscope measurements, wherein each of the plurality of gyroscope measurements has an associated rotational position of a plurality of rotational positions in the tool housing;
- measuring the plurality of gyroscope measurements for the plurality of measurement durations when the at least one gyroscope is disposed at the associated rotational position of the plurality of rotational positions;
- and
- computing an azimuth of the wellbore from the plurality of gyroscope measurements.
A gyroscopic surveying tool comprising:
- at least one gyroscope deployed in and disposed to rotate with respect to a tool housing, wherein the at least one gyroscope includes a micro electro mechanical systems (MEMS) gyroscope;
- and
- a processor configured to:
- determine a pitch angle and a roll angle of the gyroscopic surveying tool in a wellbore;
- determine, using the pitch angle and the roll angle, a plurality of measurement durations, each measurement duration of the plurality of measurement durations associated with an associated gyroscope measurement of a plurality of gyroscope measurements, wherein each of the plurality of gyroscope measurements has an associated rotational position of a plurality of rotational positions in the tool housing;
- measure the plurality of gyroscope measurements for the plurality of measurement durations when the at least one gyroscope is disposed at the associated rotational position of the plurality of rotational positions;
- and
- compute an azimuth of the wellbore from the plurality of gyroscope measurements.
A method for surveying a wellbore, the method comprising:
- deploying a gyroscopic surveying tool in the wellbore, the gyroscopic surveying tool including a single axis gyroscope disposed to rotate in and with respect to a tool housing, wherein the gyroscopic surveying tool includes a micro electro mechanical systems (MEMS) gyroscope;
- computing a pitch angle and a roll angle of the gyroscopic surveying tool in the wellbore;
- determining a first measurement duration, a second measurement duration, and a third measurement duration corresponding to a first gyroscope measurement, a second gyroscope measurement, and a third gyroscope measurement from the pitch angle and the roll angle;
- measuring the first gyroscope measurement, the second gyroscope measurement, and the third gyroscope measurement at the first measurement duration, the second measurement duration, and the third measurement duration, respectively, when the single axis gyroscope is disposed at a corresponding first rotational position, second rotational position, and third rotational position in the tool housing;
- and
- computing an azimuth of the wellbore from the first gyroscope measurement, the second gyroscope measurement, and the third gyroscope measurement.
Dependencies are inferred from the claim text.