Single and multi-trace omnidirectional sonde and line locators and transmitter used therewith

Abstract

At least one antenna array including three mutually orthogonal antennas each sharing a common center point senses an electromagnetic signal emitted by a buried object such as a utility line, pipe or sonde. A circuit at least partially mounted in a housing is connected to the array and determines a location of the buried object by measuring signal strength and field angles in three dimensions without having to align the antenna array relative to the buried object while eliminating nulls and false peaks. A graphical user interface (GUI) has user-friendly icons, symbols, menus, numbers and graphical and auditory representation of signal strength. A plurality of different underground objects can be simultaneously detected and their different locations can be simultaneously indicated to a user via audible sounds and/or visual images on a display.

What is claimed is:  
     
         1 . An omnidirectional manually portable system for locating a plurality of buried objects that emit different electromagnetic signals, comprising: 
 at least one antenna array including a plurality of antennas;    a portable housing connected to and supporting the antenna array; and    circuit means at least partially mounted in the housing and connected to the antenna array for simultaneously sensing a plurality of different electromagnetic signals emitted from a plurality of buried objects and simultaneously indicating a plurality of different locations of the buried objects.    
     
     
         2 . The system of  claim 1  wherein the circuit means determines the different locations by measuring signal strength and field angles in three dimensions.  
     
     
         3 . The system of  claim 1  wherein the circuit means includes a display mounted in the housing and means for driving the display to provide a visual indication of the different locations of the buried objects.  
     
     
         4 . The system of  claim 1  wherein the circuit means includes an audio transducer and means for driving the audio transducer to provide audible indications of the different locations of the buried objects.  
     
     
         5 . The system of  claim 1  wherein the circuit means simultaneously indicates the orientation of a plurality of buried long conductors.  
     
     
         6 . The system of  claim 1  wherein the circuit means simultaneously displays a plurality of icons indicative of the different buried objects.  
     
     
         7 . The system of  claim 1  wherein the circuit means simultaneously displays a plurality of different buried objects in a plurality of different colors, each of the colors being associated with a particular type of object.  
     
     
         8 . The system of  claim 1  wherein the one antenna array includes three substantially mutually orthogonal antennas.  
     
     
         9 . The system of  claim 1  wherein the one antenna array includes at least four substantially non-coplanar and substantially non-co-axial  
     
     
         10 . The system of  claim 1  and further comprising an elongate member connecting the one antenna array and the housing and at least one remote antenna spaced from the one antenna array and connected to the circuit means for determining the depths of the buried objects based on the electromagnetic signals sensed by all of the antennas.  
     
     
         11 . A method of locating a plurality of buried objects by sensing a plurality of different electromagnetic signals emitted by the objects, comprising the steps of: 
 traversing a topside area beneath which a plurality of objects emitting a plurality of different electromagnetic signals are buried with at least one antenna array;    sensing the electromagnetic signals emitted from the buried objects with the one array; and    simultaneously determining a plurality of different locations of the buried object based on the sensed electromagnetic signals and simultaneously indicating the different locations to a user.    
     
     
         12 . The method of  claim 11  wherein the locations of the buried objects are sensed without having to align the one antenna array relative to the buried objects and while eliminating nulls and false peaks.  
     
     
         13 . The method of  claim 11  wherein the antenna array includes three mutually orthogonal antennas.  
     
     
         14 . The method of  claim 11  and further comprising the step of simultaneously providing a plurality of different visual indications of the different locations of the buried objects.  
     
     
         15 . The method of  claim 11  and further comprising the step of simultaneously providing a plurality of different audible indications of the different location of the buried objects.  
     
     
         16 . The method of  claim 13  wherein the topside area is simultaneously traversed with a fourth antenna spaced from the one antenna array and a plurality of different depths of the buried objects are determined based on the electromagnetic signals sensed by all of the antennas.  
     
     
         17 . The method of  claim 11  and further comprising the step of simultaneously displaying a plurality of icons indicative of the different buried objects.  
     
     
         18 . The method of  claim 11  and further comprising the step of simultaneously displaying a plurality of different buried objects in a plurality of different colors, each of the colors being associated with a particular type of object.  
     
     
         19 . The method of  claim 11  and further comprising the step of simultaneously indicating the orientation of a plurality of buried long conductors.  
     
     
         20 . An omnidirectional manually portable system for locating a plurality of buried objects by sensing a plurality of different electromagnetic signals emitted by the objects, comprising: 
 a first antenna array including three substantially mutually orthogonal antennas in the form of a first plurality of coils sharing a first common center point;    a second antenna array including three substantially mutually orthogonal antennas in the form of a second plurality of coils sharing a second common center point;    a portable housing including a handle portion;    an elongate member connecting the first and second antenna arrays to the housing and extending through the first and second common center points and supporting the first and second antenna arrays in spaced apart relation; and    circuit means at least partially mounted in the housing and connected to the antennas in the first and second antenna arrays for sensing electromagnetic signals in a plurality of different bands emitted by a plurality of different buried objects and determining a location and a depth of each of the plurality of buried objects by measuring signal strength and field angles in three dimensions for each buried object utilizing the first and second antenna arrays, the circuit means including means for simultaneously providing visual and/or audible indications of the location and depth of each of the plurality of buried objects.    
     
     
         21 . A transmitter for use with a line locator, comprising: 
 a portable housing having at least a pair of outwardly opening pockets;    a control panel mounted on the housing for receiving manually inputted commands;    an electronic circuit mounted in the housing for receiving the commands from the control panel and generating a predetermined electrical output signal in response to the commands;    at least a pair of electrical cords each stowable in a corresponding one of the pockets, the electrical cords each having an inner end electrically connected to the electronic circuit, and    means electrically connected to an outer end of each of the electrical cords for coupling the predetermined electrical signal across a selected utility line.    
     
     
         22 . The transmitter of  claim 21  wherein the housing has an elongate configuration and there are two pockets, each pocket being formed in an opposite end of the elongate housing.  
     
     
         23 . The transmitter of  claim 21  wherein the electrical cords are coil cords.  
     
     
         24 . The transmitter of  claim 21  wherein the electrical cords each have an inner steel conductor.  
     
     
         25 . The transmitter of  claim 21  wherein the control panel includes a keypad.  
     
     
         26 . The transmitter of  claim 21  wherein the control panel includes a display and the electronic circuit is connected to the display for depicting alphanumeric and graphic information indicating the selected commands.  
     
     
         27 . The transmitter of  claim 21  wherein the coupling means is selected from the group consisting of a clip, an inductive antenna and an inductive clamp.  
     
     
         28 . The transmitter of  claim 21  wherein at least one of the clips has a circuit including at least one illumination device that is energized to provide a visible signal when the clip is coupled to a line having the electrical output signal applied thereto.  
     
     
         29 . The transmitter of  claim 21  and further including a ground spike and means on the housing for removably receiving and holding the ground spike.  
     
     
         30 . The transmitter of  claim 21  wherein the control pad includes means for providing a visible luminous signal in a color that is normally associated with a particular type of underground utility when a frequency for tracing that type of underground utility has been manually selected.  
     
     
         31 . A transmitter for use with a line locator, comprising: 
 a portable housing;    a control panel mounted on the housing for receiving manually inputted commands;    an electronic circuit mounted in the housing for receiving the commands from the control panel and generating a predetermined electrical output signal in response to the commands, including means for selecting one of a plurality of different frequency bands and means for selecting a channel frequency within the selected one of the bands that is uniquely associated with one of a plurality of different types of utilities; and    means for coupling the predetermined electrical output signal across a selected utility line.    
     
     
         32 . The transmitter of  claim 31  wherein the control panel includes a keypad.  
     
     
         33 . The transmitter of  claim 31  wherein the control panel includes a display and the electronic circuit is connected to the display for depicting alphanumeric and graphic information indicating the selected commands.  
     
     
         34 . The transmitter of  claim 31  wherein the control pad includes means for providing a visible luminous signal in a color that is normally associated with a particular type of underground utility when a channel frequency for tracing that type of underground utility has been manually selected.  
     
     
         35 . The transmitter of  claim 31  wherein the control panel includes means driven by the electronic circuit to indicate to a user that a hazardous voltage across the selected utility line has been detected.  
     
     
         36 . A clip for use with a transmitter that energizes a buried object for detection by a locator, comprising: 
 mechanical meas for establishing an electrical connection to a surface accessible part of the buried object for applying a predetermined output signal from a transmitter to the buried object; and    means associated with the mechanical means for providing a luminous signal to a user indicating that the predetermined output signal has been applied across the buried object.    
     
     
         37 . The clip of  claim 36  wherein the mechanical means includes an alligator clip.  
     
     
         38 . The clip of  claim 37  wherein the means for providing the luminous signal to the user includes a circuit having at least one LED.  
     
     
         39 . The clip of  claim 38  wherein the means for providing the luminous signal to the user includes a light pipe for transmitting light from the LED to the user.  
     
     
         40 . The clip of  claim 39  wherein the circuit is enclosed within a housing connecting the mechanical means to a cord that transmits the predetermined output signal from the transmitter.