07093370 is referenced by 32 patents and cites 25 patents.

An omnidirectional borehole navigation system is provided that includes a housing that can be placed within the smaller diameter drill pipes used towards the bottom of a borehole, an outer gimbal connected to the housing, and at least two or more stacked inner gimbals that are nested in and connected to the outer gimbal, the inner gimbals each having an axis parallel to one another and perpendicular to the outer gimbal. The inner gimbals contain electronic circuits, gyros whose input axes span three dimensional space, and accelerometers whose input axes span three dimensional space. There are an outer gimbal drive system, an inner gimbal drive system for maintaining the gyro input axes and the accelerometer input axes as substantially orthogonal triads, and a processor responsive to the gyro circuits and the accelerometer circuits to determine the attitude and the position of the housing in the borehole.

Title
Multi-gimbaled borehole navigation system
Application Number
10/987117
Publication Number
7093370 (B2)
Application Date
November 12, 2004
Publication Date
August 22, 2006
Inventor
Richard T Martorana
Andover
MA, US
Michael E Ash
Lexington
MA, US
Mitchell L Hansberry
Southborough
MA, US
Agent
Iandiorio & Teska
Assignee
The Charles Stark Draper Laboratory
MA, US
IPC
G01C 19/00
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