1
Kevin L Alft, Gregory W Draper, Hans Kelpe: Horizontal directional drilling machine and method employing configurable tracking system interface. Vermeer Manufacturing Company, Crawford PLLC, November 26, 2002: US06484818 (120 worldwide citation)

A system and method for controlling an underground boring tool involves the use of one or more of a gyroscope, accelerometer, and magnetometer sensor provided in or proximate the boring tool. The location of the boring tool is detected substantially in real-time. A controller produces a control sign ...


2
Kevin L Alft, Gregory W Draper: Horizontal directional drilling machine employing inertial navigation control system and method. Vermeer Manufacturing Company, Altera Law Group, November 13, 2001: US06315062 (119 worldwide citation)

A system and method for controlling an underground boring tool involves the use of one or more of a gyroscope, accelerometer, and magnetometer sensor provided in or proximate the boring tool. The location of the boring tool is detected substantially in real-time. A controller produces a control sign ...


3
Gregory W Draper, Frank S Nickel, Michael F Gard, Jian J Jin: Avoiding ghosting artifacts during surface location of subsurface transmitters. The Charles Machine Works, Sidley & Austin, April 15, 1997: US05621325 (60 worldwide citation)

An apparatus and method is provided for determining if the signal received from an underground beacon (10) at a locator (22) is a true signal or a ghost signal. Orthogonal horizontal antenna (38) and vertical antenna (40) are used and a ratio is computed of the signal strengths measured by the two a ...


4
Kevin L Alft, Gregory W Draper, Hans Kelpe: Underground boring machine employing navigation sensor and adjustable steering. Vermeer Manufacturing Company, Crawford Maunu PLLC, April 13, 2004: US06719069 (35 worldwide citation)

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 a ...


5
Kevin L Alft, Gregory W Draper, Hans Kelpe: Earth penetrating apparatus and method employing radar imaging and rate sensing. Vermeer Manufacturing Company, Hollingsworth & Funk, December 5, 2006: US07143844 (34 worldwide citation)

An earth penetrating apparatus includes a cutting tool and a sensor housing. A radar unit, rate sensor unit, processor, and transmitter are provided in the sensor housing. An antenna arrangement is coupled to the radar unit and configured for transmitting and receiving electromagnetic signals in a r ...


6
Kevin L Alft, Gregory W Draper, Hans Kelpe: Earth penetrating apparatus and method employing radar imaging and rate sensing. Vermeer Manufacturing Company, Hollingsworth & Funk, October 27, 2009: US07607494 (13 worldwide citation)

An earth penetrating apparatus includes a cutting tool and a sensor housing. A radar unit, rate sensor unit, processor, and transmitter are provided in the sensor housing. An antenna arrangement is coupled to the radar unit and configured for transmitting and receiving electromagnetic signals in a r ...


7
Kevin L Alft, Gregory W Draper, Hans Kelpe: Underground boring machine employing solid-state inertial navigation control system and method. Vermeer Manufacturing Company, Mark A Hollingsworth, Altera Law Group, January 17, 2002: US20020005297-A1 (1 worldwide citation)

A system and method for controlling an underground boring tool involves the use of one or more of a gyroscope, accelerometer, and magnetometer sensor provided in or proximate the boring tool. The location of the boring tool is detected substantially in real-time. A controller produces a control sign ...


8
Kevin L Alft, Gregory W Draper, Hans Kelpe: Underground boring machine employing navigation sensor and adjustable steering. Vermeer Manufacturing Company, Crawford PLLC, June 19, 2003: US20030111268-A1 (1 worldwide citation)

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 a ...


9
Kevin L Alft, Gregory W Draper, Hans Kelpe: Earth penetrating apparatus and method employing radar imaging and rate sensing. Vermeer Manufacturing Company, Crawford Maunu PLLC, September 30, 2004: US20040190374-A1

An earth penetrating apparatus includes a cutting tool and a sensor housing. A radar unit, rate sensor unit, processor, and transmitter are provided in the sensor housing. An antenna arrangement is coupled to the radar unit and configured for transmitting and receiving electromagnetic signals in a r ...


10
Kevin L Alft, Gregory W Draper, Hans Kelpe: Earth penetrating apparatus and method employing radar imaging and rate sensing. Vermeer Manufacturing Company, Attention of Mark A Hollingsworth, Hollingsworth & Funk, October 18, 2007: US20070240903-A1

An earth penetrating apparatus includes a cutting tool and a sensor housing. A radar unit, rate sensor unit, processor, and transmitter are provided in the sensor housing. An antenna arrangement is coupled to the radar unit and configured for transmitting and receiving electromagnetic signals in a r ...