07117605 is referenced by 24 patents and cites 47 patents.

A system and method for determining an orientation of the survey tool within a borehole utilizes a survey tool including a plurality of rotation sensors each having a sensing axis and a direction of least acceleration sensitivity. The plurality of rotation sensors are mounted in a housing with their sensing axes generally parallel to one another and with their directions of least acceleration sensitivity generally non-parallel to one another. The survey tool further includes a controller adapted to calculate a weighted average of the detected angular rotation rates from the plurality of rotation sensors. The weighted average includes the detected angular rotation rate of each rotation sensor about its sensing axis weighted by the detected acceleration along its direction of least acceleration sensitivity.

Title
System and method for using microgyros to measure the orientation of a survey tool within a borehole
Application Number
10/823091
Publication Number
7117605 (B2)
Application Date
April 13, 2004
Publication Date
October 10, 2006
Inventor
Gary William Uttecht
Houston
TX, US
Roger Ekseth
Sjetnemarka
NO
Agent
Knobbe Martens Olson & Bear
Assignee
Gyrodata Incorporated
TX, US
IPC
E21B 47/22
G01C 21/16
G01C 19/56
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