06411094 is referenced by 75 patents and cites 2 patents.

A system and method use magnetic field sensing to detect underground objects for strike avoidance. The system detects magnetic field components for both passive distortions in the magnetic field indicative of a ferromagnetic object and active magnetic fields that are impressed on an object by a signal generator. A detection module has a magnetic sensor assembly that detects the magnetic field components. The magnetic field component data is transferred through a multiplexer to an analog/digital converter to a processor. Pitch angle data from a pitch sensor and roll angle data from a roll sensor also may be transferred to the processor. The data is processed by the processor to determine the orientation of the detection module with respect to the object. The detection module may be installed in an underground boring tool or a trenching assembly.

Title
System and method for determining orientation to an underground object
Application Number
8/999166
Publication Number
6411094 (B1)
Application Date
December 30, 1997
Publication Date
June 25, 2002
Inventor
Jian Jin
Perry
OK, US
Michael F Gard
Perry
OK, US
Agent
McKinney & Stringer PC
US
Assignee
The Charles Machine Works
OK, US
IPC
G01V 3/28
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