1
Michael F Gard, Jian Jin, John C Wisehart: Electronic compass. The Charles Machine Works, Sidley & Austin, December 15, 1998: US05850624 (134 worldwide citation)

An electronic compass (10) for use in a boring tool (12) which will provide an orientation of the boring tool relative to the earth's magnetic field. In addition, a more straightforward left or right deviation from an initial bearing can be determined. The invention can correct for pitch angle and r ...


2
John A Hanpeter, Seth A Eisen, Michael F Gard: Medication compliance monitoring device having conductive traces upon a frangible backing of a medication compartment. The United States of America represented by the Administrator of Veterans Affairs, Browdy and Neimark, October 7, 1986: US04616316 (112 worldwide citation)

A medication compliance monitoring system consisting of a blister pack having an array of plastic blisters defining compartments for medication, with a frangible non-conductive backing sheet having conductive traces behind the compartments which are respectively ruptured when the medication doses ar ...


3
Michael F Gard, Jian Jin: System and method for determining orientation to an underground object. The Charles Machine Works, McKinney & Stringer PC, June 25, 2002: US06411094 (75 worldwide citation)

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 sign ...


4
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 ...


5
Michael F Gard, Jian Jin: System and method for detecting an underground object using magnetic field sensing. The Charles Machine Works, Tomlinson & O Connell PC, May 2, 2006: US07038454 (45 worldwide citation)

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 sign ...


6
Jiang Hsieh, Michael F Gard, Cameron J Ritchie: Methods for reducing motion induced artifacts in a projection imaging system. General Electric Company, Quarles & Brady, December 14, 1993: US05271055 (45 worldwide citation)

A medical imaging system has a source of X-rays and a detector which produces an electrical signal in response to X-rays. A signal generated by the detector, during an acquisition interval, is used to construct an image of a medical patient, which may contain artifacts due to motion of patient. A si ...


7
Michael F Gard, Stephen W Gravelle, Jiang Hsieh, Quan N Lu, John W Newman, Thomas L Toth, Michael A Wu: Alignment of an x-ray tube focal spot using a deflection coil. General Electric, Quarles & Brady, August 27, 1996: US05550889 (44 worldwide citation)

Precise alignment of the focal spot position on an x-ray CT system is achieved using a deflection coil that produces a magnetic field which acts on the electron beam path in the x-ray tube. A variable current power supply drives the deflection coil and is controlled by input signals to align the foc ...


8
Michael F Gard: Balanced passive bandpass filter and preamplifier for a receiver. The Charles Machine Works, Sidley & Austin, May 25, 1999: US05907242 (32 worldwide citation)

A balanced bandpass preamplifier assembly (23) is disclosed for use in a locator (10) for locating a beacon transmitter (18) housed within an underground boring device (12). The bandpass preamplifier assembly (23) includes a balanced bandpass filter (28) of the Butterworth type with second order fil ...


9
Michael F Gard, John E E Kingman, James D Klein: Method and apparatus for measuring the electrical resistivity of geologic formations through metal drill pipe or casing. Atlantic Richfield Company, Michael E Martin, June 6, 1989: US04837518 (28 worldwide citation)

The resistivity of a geologic formation is measure through drillpipe or casing by applying a low frequency bipolar voltage to the casing and to a ground electrode and traversing the casing with a tool having contractors which are connected to a differential amplifier to detect a differential voltage ...


10
Michael F Gard: Transient electromagnetic apparatus with receiver having digitally controlled gain ranging amplifier for detecting irregularities on conductive containers. Atlantic Richfield Company, Geoffrey Mantooth, March 6, 1990: US04906928 (28 worldwide citation)

A transient electromagnetic apparatus for use in detecting irregularities on conductive walls of containers forms a multichannel distributed system and includes at least one transmitting antenna, at least one transmitter unit, plural receiving antennas, plural receiver units, and a computer for cont ...