06470976 is referenced by 46 patents and cites 2 patents.

Systems and methods for controlling an underground boring tool involve rotating the boring tool and sensing a parameter of boring tool rotation. The boring tool is also displaced along an underground path and a parameter of boring tool displacement is sensed. Various sensors monitor boring machine activities, boring tool location, orientation, and environmental condition, and geophysical and/or geologic condition of the soil/rock at the excavation site. Data acquired by these sensors is processed by a boring machine controller to provide closed-loop, real-time control of a boring operation. The controller receives the boring tool signal and other sensor signals in real-time and, in response, transmits control signals to each of the rotation and displacement units substantially in real-time so as to control one or both of a rate and a direction of boring tool movement along the underground path.

Title
Excavation system and method employing adjustable down-hole steering and above-ground tracking
Application Number
9/955675
Publication Number
6470976 (B2)
Application Date
September 19, 2001
Publication Date
October 29, 2002
Inventor
Hans Kelpe
Pella
IA, US
Gregg A Austin
Pella
IA, US
Brian J Bischel
Hartland
WI, US
Kevin L Alft
Pella
IA, US
Agent
Crawford Maunu PLLC
US
Assignee
Vermeer Manufacturing Company
IA, US
IPC
E21B 7/04
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