TECHNICAL FIELD

Embodiments of the present invention are related to underground line location and, in particular, to an underground locator system with real-time kinematic and global satellite positioning.

DISCUSSION OF RELATED ART

The process of locating buried utilities (pipes and cables) using low frequency signals is well known and widely adopted as a work practice. Line locating instruments typically include an array of spaced antennas that receive time-varying magnetic field signals generated by the underground utility itself. Such signals can be the result of currents coupled into the underground utility by a separate transmitter or are inherent in the underground utility, for example from power lines. The array of spaced antennas receives the magnetic fields, which are often at specific frequencies. Processing electronics in the line locating instrument determines the relative utility position from the line locating system, including depth, signal currents and other information. Horizontal position and depth of the underground utility, for example, can then be displayed to the user and, in some systems, recorded relative to the position of the line locator.

Increasingly, applications for line locating systems are used in mapping utilities. These mappings of underground utilities are desired to be as geographically accurate as possible. Therefore, there is a need to develop line location systems with highly accurate positional determination.

SUMMARY

According to some embodiments, precise line locator for precise location of an underground line is presented. A precise line locator according to some embodiments includes a housing; a wand attached to the housing, the wand including an array of low frequency antennas arranged along the wand, the array of low frequency antennas defining an electromagnetic locate axis of the line locator system; a real-time kinematic (RTK) Global Navigation Satellite (GNSS) antenna attached to the housing; a user interface positioned in the housing; and a processing circuit coupled to the array of low frequency antennas, the RTK GNSS antenna, and the user interface, wherein the underground line locator determines locate data of the underground line based on signals from the array of low frequency antennas and determines a precise position of the underground line locator from the RTK GNSS antenna.

A method of precisely determining position of an underground line includes locating an underground line at a position with a precise line locator, the precise line locator having an array of low frequency antennas arranged along a wand, the array of low frequency antennas defining an electromagnetic locate axis; placing the precise line locator in a first orientation; determining and logging line location data; placing the precise line locator in a second orientation where a real-time kinematic (RTK) Global Navigation Satellite (GNSS) antenna is positioned to provide a precise position; and determining and logging the precise position with the line location data.

These and other embodiments are discussed below with respect to the following figures.

