06719069 is referenced by 35 patents and cites 2 patents.

An excavation system includes a cutting tool coupled to a drill pipe, an adjustable steering mechanism provided on or in the cutting tool, and a driving apparatus coupled to the drill pipe for moving the cutting tool along an underground path. The system further includes a navigation sensor system and a controller. The controller produces a control signal to adjust one or both of the steering mechanism and the driving apparatus for directing the cutting tool along the underground path in accordance with one or both of position information and orientation information produced by the navigation sensor system.

Title
Underground boring machine employing navigation sensor and adjustable steering
Application Number
10/304185
Publication Number
6719069 (B2)
Application Date
November 25, 2002
Publication Date
April 13, 2004
Inventor
Hans Kelpe
Pella
IA, US
Gregory W Draper
Pella
IA, US
Kevin L Alft
Pella
IA, US
Agent
Crawford Maunu PLLC
US
Assignee
Vermeer Manufacturing Company
IA, US
IPC
E21B 44/00
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