US 12,007,491 B2
GPS assisted walkover locating system and method
Scott B. Cole, Edmond, OK (US); Brian J. Schrock, Fulshear, TX (US); and Klayton Day Jones, Perry, OK (US)
Assigned to The Charles Machine Works, Inc., Perry, OK (US)
Filed by The Charles Machine Works, Inc., Perry, OK (US)
Filed on Jul. 5, 2022, as Appl. No. 17/857,623.
Application 17/857,623 is a continuation of application No. 16/549,740, filed on Aug. 23, 2019, granted, now 11,397,266, issued on Jul. 26, 2022.
Claims priority of provisional application 62/724,161, filed on Aug. 29, 2018.
Prior Publication US 2022/0334266 A1, Oct. 20, 2022
Int. Cl. G01S 19/45 (2010.01); G01S 19/48 (2010.01); G01V 3/08 (2006.01); G01S 5/00 (2006.01); G01S 19/38 (2010.01); G01S 19/42 (2010.01)
CPC G01S 19/45 (2013.01) [G01S 19/48 (2013.01); G01V 3/081 (2013.01); G01S 5/018 (2020.05); G01S 19/38 (2013.01); G01S 19/42 (2013.01)] 14 Claims
OG exemplary drawing
 
1. An above-ground tracking system, comprising:
a portable frame extending from a first end to a second end;
a display disposed on the frame proximate the second end;
a receiving antenna supported by the frame proximate the first end, wherein the receiving antenna is responsive to a magnetic dipole field;
a global positioning system receiver supported by the frame;
a processor coupled to the antenna and receiver; and
a memory coupled to the processor having program instructions stored therein which, when executed by the processor, perform the steps of:
in response to a first and single user request, obtaining a first set of measurements comprising:
a location measurement from the global positioning receiver; and
a magnetic field measurement from the receiving antenna; and
thereafter, obtaining iterative sets of measurements, comprising:
a location measurement from the global positioning receiver; and
a magnetic field measurement from the receiving antenna;
determining from the magnetic field measurements of the first set of measurements and iterative sets of measurements, as the location measurement and magnetic field measurement change, a relative position of a null location within the magnetic field at which the magnetic dipole field is vertical; and
recording an absolute position of the null location within the magnetic dipole field using the location measurement of the first and iterative sets of measurements and the relative position.