US 12,461,271 B1
Dual sensed locating systems and methods
Mark S. Olsson, La Jolla, CA (US); and Michael J. Martin, San Diego, CA (US)
Assigned to SeeScan, Inc., San Diego, CA (US)
Filed by SeeScan, Inc., San Diego, CA (US)
Filed on Dec. 2, 2021, as Appl. No. 17/540,239.
Application 17/540,239 is a continuation of application No. 17/068,156, filed on Oct. 12, 2020, granted, now 11,204,436.
Application 17/068,156 is a continuation of application No. 13/787,711, filed on Mar. 6, 2013, granted, now 10,809,408, issued on Oct. 20, 2020.
Claims priority of provisional application 61/607,510, filed on Mar. 6, 2012.
This patent is subject to a terminal disclaimer.
Int. Cl. G01V 3/08 (2006.01); G01V 11/00 (2006.01); H04N 7/18 (2006.01)
CPC G01V 3/087 (2013.01) [G01V 11/00 (2013.01); H04N 7/183 (2013.01)] 16 Claims
OG exemplary drawing
 
1. A system for locating buried objects, comprising:
a push-cable including an electrical conductor;
a sonde mechanically coupled to the push-cable for generating a dipole magnetic field sonde signal at a first frequency;
a transmitter electrically coupled to the push-cable electrical conductor for providing a current signal to the push-cable to generate a line trace current signal, wherein a circular magnetic field signal is generated from the line trace current signal flowing in the push-cable;
at a second frequency different from the first frequency, resulting from current flow in the electrical conductor; and
a locator comprising:
a receiver module configured to receive the circular magnetic field signal and the sonde dipole magnetic field signal and provide a corresponding line trace output signal and a sonde output signal;
a processing element configured to:
receive the line trace output signal and the sonde output signal and generate, based at least in part on the line trace output signal and the sonde output signal, information associated with a buried object, wherein the information associated with the buried object includes determining an indication of ambiguity and providing the indication of ambiguity on an output device when the measured sonde dipole magnetic field signal axis and the push-cable circular magnetic field signal axis are not aligned as determined by a difference in alignment between the axes; and
an output device operatively coupled to the processing element to provide a representation of the information associated with the buried object.