05220963 is referenced by 124 patents and cites 11 patents.

An improved method and apparatus for automatically controlling the direction of advance of a rotary drill to produce a borehole profile substantially as preplanned with minimal curvature while maintaining optimum drilling performance. The system is capable of storing a planned path for the borehole. Information relating to the profile of the actual drill path is compared to the planned path and an appropriate correction signal is generated and used to cause the borehole to be drilled in accordance with the planned path.

Title
System for controlled drilling of boreholes along planned profile
Application Number
7/455255
Publication Number
5220963
Application Date
December 22, 1989
Publication Date
June 22, 1993
Inventor
Bob J Patton
Dallas
TX, US
Agent
Pravel Gambrell Hewitt Kimball & Krieger
Assignee
Patton Consulting
TX, US
IPC
E21B 44/00
E21B 7/04
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