Abstract:
A mobile apparatus for monitoring an electric field in a patrolled area, comprising at least one detection device for measuring electric field signals, at least one camera device for collecting video images of said patrolled area, a processor for correlating video image data collected from the camera device with electric field signal data measured by the detection device, and a video based graphical user interface for analyzing and capturing a monitored event depicting an anomaly in the measured electric field signals.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
   This patent application claims the benefit of U.S. Provisional Patent Application No. 60/728,168, filed Oct. 19, 2005, which is hereby incorporated by reference in its entirety. This patent application is also a continuation-in-part of and claims priority to U.S. patent application Ser. No. 11/224,909, filed Sep. 13, 2005, now U.S. Pat. No. 7,248,054. 

   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to the detection of electric fields. More particularly, the present invention is directed to an apparatus and method employing a video graphical user interface configured to enhance mobile detection and monitoring of stray voltage anomalies. 
   2. Description of the Related Art 
   Large power distribution systems, especially those in large metropolitan areas, are subject to many stresses, which may occasionally result in the generation of undesirable or dangerous anomalies. Ah infrequent, but recurrent problem in power distribution infrastructures is the presence of “stray voltages” in the system. These stray voltages may present themselves when objects, such as manhole covers, gratings, street light poles, phone booths and the like become electrically energized (e.g., at 120V AC). An electrically conductive path may be established between underground secondary network cabling and these objects through physical damage to electrical insulation resulting in direct contact between electrically conductive elements or through the introduction of water acting as a conductor. These energized objects present obvious dangers to people and animals in the general public. 
   Detecting the existence of stray voltages by means of assessing electromagnetic radiation is not practical because the wavelength of a 60 Hz electromagnetic wave is approximately 5,000 kilometers (i.e., about 3,107 miles) in length. To effectively radiate electromagnetic waves, a radiating object (e.g., manhole cover or light pole) should represent at least ¼ wavelength (i.e., about 776.75 miles) and a receiving “antenna” should be 1½ to 2 wavelengths away from the emitting source (about 6,214 miles). Two wavelengths is the distance required for electric and magnetic fields to come into time phase and space quadrature where they behave as a plane wave. A detection system will typically be perhaps 10 ft. to 30 ft. away from the energized object, so that detection will take place in the extreme near field where electric and magnetic fields exist in a complex temporal and spatial pattern, not as a unified electromagnetic plane wave. Thus, electric and magnetic fields must be considered and measured separately. 
   Due to power distribution networks typically having many miles of buried cable carrying perhaps thousands of amperes of current, the magnetic field in any one location due to such normal load is likely to be very high. Detecting magnetic fields arising from a relatively weak stray voltage anomaly would be very difficult due to the interference from strong ambient magnetic fields arising from normal loads and, therefore, it has been determined that the best way to detect a stray voltage anomaly is to assess the electric field. 
   Techniques for the detection of stray voltages are typically carried out by manual inspection of surrounding electrical infrastructures for signs of leaking current. An inspection team equipped, for example, with hand held detection devices may be employed to make direct physical inspections of electrical infrastructures. However, inspectors using these detection devices are typically required to make contact with portions of electrical infrastructures, such as streetlamp bases or manhole covers, in order to obtain accurate measurements for determining the existence of potentially dangerous stray voltages. These manual inspections are undoubtedly time-consuming and give a false sense of security. 
   Accordingly, there exists a need to provide a more efficient means for detecting and identifying sources of stray voltage anomalies over vast geographic areas, particularly, populated urban, suburban and rural areas. 
   SUMMARY OF THE INVENTION 
   In view of the foregoing, it is an object of the present invention to provide a mobile stray voltage detection apparatus and method configured to sense potentially dangerous stray voltage anomalies from a moving vehicle. 
   It is another object of the present invention to provide a mobile stray voltage detection apparatus and method configured to provide real-time awareness of detected stray voltage anomalies, thereby enabling rapid and efficient inspection of surrounding patrolled areas. 
   It is yet another object of the present invention to provide a mobile stray voltage detection apparatus and method configured to provide accurate location and visual identification of potential hazards. 
   These and other objects of the present invention are accomplished in accordance with the principles of the present invention by providing a mobile stray voltage detection system integrated with a user-controllable monitoring interface, wherein the user interface is a video based graphical user interface configured to enhance the detection of stray voltage anomalies. Input to the mobile stray voltage detection system is provided by at least one vehicle mounted sensor probe, which is sensitive to the presence of an electric field in at least one axis. Such a vehicle mounted sensor probe system is described, for example, in commonly owned U.S. Pat. No. 7,248,054 issued Jul. 24, 2007 and U.S. Pat. No. 7,253,642 issued Aug. 7, 2007, which are hereby incorporated by reference. The vehicle is additionally mounted with at least one camera unit for recording a scene being patrolled for stray voltage anomalies using the vehicle mounted sensor probe. Intensity of electric field signals are communicated to an operator through means of an audio tone that is pitch proportional to strength of the field detected, as well as through a visual display, both user communication means being controllable through the user interface. Distance traveled by the vehicle, as well as GPS positions of the vehicle throughout various points of the vehicle&#39;s travel, are also provided as input to the mobile stray voltage detection system in order to tag the location of measured electric fields and further assist the operator in isolating an anomaly-emitting source. 
   In accordance with the present invention, the graphical user interface provides a video display for depicting a graphical representation of the electric field signal strength and corresponding video image of a patrolled scene. Vehicle mounted camera units present video images of the passing scene on the video display portion of the user interface. Signals measured by the sensor probe are analyzed by a processing unit to produce a “moving chart” graphical display of the electric field strength. The graphical display of the measured field strength are associated with and overlaid on the video images of the patrolled scene, thereby assisting a user to isolate and associate the source of the stray voltage anomaly to specific infrastructures depicted in the patrolled scene. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The above and other objects and advantages of the present invention will become apparent upon consideration of the following detailed description, taken in conjunction with the accompanying drawings, in which like reference characters refer to like parts throughout, and in which: 
       FIG. 1  illustrates a block diagram of an exemplary apparatus suitable for implementing the stray voltage detection methods employed in accordance with an embodiment of the present invention. 
       FIG. 2  illustrates an exemplary login display produced by a system in accordance with an embodiment of the present invention. 
       FIG. 3  illustrates an exemplary main display produced by a system upon successful logging in of an operator at the illustrative display in  FIG. 2  in accordance with an embodiment of the present invention. 
       FIG. 4  illustrates the main display of  FIG. 2  depicting streaming data of measured electric fields and corresponding video images of a patrolled scene in accordance with an embodiment of the present invention. 
       FIG. 5  illustrates an exploded view of an exemplary monitoring control panel provided on the main displays of  FIGS. 3 and 4  in accordance with an embodiment of the present invention. 
       FIG. 6  illustrates an exemplary standby display produced by the system upon selection of an event capture option provided on the main displays of  FIGS. 3 and 4  in accordance with an embodiment of the present invention. 
       FIG. 7  illustrates an exemplary event capture display produced by the system upon completion of the processing for a request to capture an event in accordance with an embodiment of the present invention. 
       FIG. 8  illustrates an exploded view of plotted electric field measurements and a location indicator provided on the playback display of  FIG. 7  in accordance with an embodiment of the present invention. 
       FIG. 9  illustrates an exploded view of plotted electric field measurements and a potentially electrified source provided on the playback display of  FIG. 7  in accordance with an embodiment of the present invention. 
       FIG. 10  illustrates an exploded view of an exemplary playback control panel provided on the event capture display of  FIG. 7  in accordance with an embodiment of the present invention. 
       FIG. 11  illustrates an exploded view of an exemplary anomaly identification sub-panel provided on the playback control panel of  FIG. 10  in accordance with an embodiment of the present invention. 
       FIG. 12  illustrates an exploded view of an exemplary event log sub-panel provided on the playback control panel of  FIG. 10  in accordance with an embodiment of the present invention. 
       FIG. 13  illustrates an exemplary preferences display produced by the system upon selection of a preferences option provided on the displays of  FIGS. 3 ,  4  and  6  in accordance with an embodiment of the present invention. 
       FIG. 14  is a flowchart illustrating the steps employed by the system in monitoring electric fields in accordance with an embodiment of the present invention. 
   

   It is to be understood that the above-identified drawing figures are for purposes of illustrating the concepts of the present invention and may not be to scale, and are not intended to be limiting in terms of the range of possible shapes and proportions of the present invention. 
   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   The present invention is directed towards a mobile apparatus and method for monitoring and controlling the detection of stray voltage anomalies in a patrolled environment. For purposes of clarity, and not by way of limitation, illustrative depictions of the present invention are described with references made to the above-identified drawing figures. Various modifications obvious to one skilled in the art are deemed to be within the spirit and scope of the present invention. 
   An exemplary apparatus  100  for implementing the present invention is illustrated in  FIG. 1 . In accordance with a preferred embodiment of the present invention, apparatus  100  is comprised of a detection system unit (DSU)  102 , which may receive electric field measurements from sensor probes  104   a ,  104   b  and  104   c . DSU  102  may employ any number of sensor probes for purposes of measuring an electric field in any particular area of interest being surveyed for stray voltage anomalies. For example, DSU  102  may employ only one of said sensor probes  104   a ,  104   b  or  104   c , additional sensor probes to supplement the measurements obtained by sensor probes  104   a ,  104   b  and  104   c  or, alternatively, any other suitable combination of sensor probes. In yet another embodiment, DSU  102  may employ a multi-axis sensor probe arrangement as the ones described, for example, in commonly owned U.S. Pat. No. 7,248,054, issued Jul. 24, 2007, and U.S. Pat. No. 7,253,642, issued Aug. 7, 2007, which are hereby incorporated by reference in their entirety. 
   Apparatus  100  of  FIG. 1  is additionally comprised of imaging system unit (ISU)  106 , which may receive video input from cameras  108   a  and  108   b.  Similar to DSU  102 , ISU  106  may employ any number of cameras suitable for providing streaming images of a patrolled scene. Cameras employed in apparatus  100  may be video cameras, stereo cameras, various digital cameras, a combination of the aforementioned cameras or any other suitable camera and arrangement of cameras suitable for imagining a patrolled scene. 
   One or more of cameras  108  may be provided for imaging the environs where apparatus  100  is employed. Specifically, where apparatus  100  is deployed on a patrol vehicle or trailer (not shown), cameras  108   a  and  108   b  may be provided thereon, wherein camera  108   a  is directed to view in a direction about 90° to the left of the direction of travel and camera  108   b  is directed to view about 90° to the right of the direction of travel, so that images of what is present to the left and to the right of the patrolling vehicle are obtained. Video images therefrom may be recorded as apparatus  100  traverses a patrolled environment. 
   Video images may be obtained at a standard video rate, e.g., at 30 or 60 frames per second, but may be at much slower rates, e.g., one or two frames per second, consistent with the speeds at which the patrolling vehicle moves. For example, if a vehicle is moving at between 10 and 20 mph (about 14-28 feet per second or about 4.2-8.5 m/sec.), video at a two frames per second video rate would provide a new image for approximately each 14 feet (about 4.2 m) or less of travel, which should be sufficient to identify the location at which the stray voltage was detected. 
   The video images may all be recorded (stored) or only selected images may be recorded. In one exemplary embodiment, video images are stored in a video frame data buffer having a capacity to store a substantial number of frames of video data, e.g., frames representing about thirty (30) seconds of video scenes. As each new frame is stored, the oldest previous frame is lost. Thus, the video data buffer contains video frames for the most recent thirty seconds. Video buffers storing frames representing a longer period of time, or even a shorter period of time, may be employed. For example, a “frame grabber” card, in the form of a PCMCIA card or an internal card, may be employed to synchronize processed electric field data DSU  102  with processed video data from ISU  106 . 
   DSU  102  and ISU  106  are coupled to a processor  110 . DSU  102  and ISU  106  may perform preprocessing of signals received, respectively, from sensor probes  104   a - 104   c  and cameras  108   a - 108   b  or, as previously described, any alternative arrangements of sensor probes and cameras prior to transmitting data to processor  110 . Processor  110  coupled to DSU  102  and ISU  106  is capable of processing sensor probe measurement data and corresponding video frame data in near real time (e.g., with less than one second latency). For example, processor  110  may be arranged to interface directly to a three-axis stray voltage sensing probe arrangement, as described in commonly owned U.S. Pat. No. 7,248,054, issued Jul. 24, 2007, and U.S. Pat. No. 7,253,642, issued Aug. 7, 2007. Processor  110  may include a plurality of electronic components (not shown) such as a multi-channel analog-to-digital converter (ADC), a digital signal processor (DSP), a memory e.g., an EEPROM), an audio amplifier, audible transducing device (e.g., a loudspeaker), one or more data converters (e.g., uni-directional or bidirectional SPI to RS-232 converters), a source of electrical power (e.g., a power converter operating from a vehicle power system) or any other applicable electronic processing component. 
   In addition to DSU  102  and ISU  106 , a wheel speed sensor  112 , a global positioning system (GPS) receiver  114 , a memory component  116 , a transceiver component  118  and a graphical user interface (GUI)  120  may also be coupled to processor  110 . Data pertaining to the speed and distance of travel of a patrolling vehicle may be provided to processor  110  by wheel speed sensor  112 . Wheel speed sensor  112  is employed in the processing of electric field data to facilitate signal processing while apparatus  100  is in motion as described herein. 
   Data pertaining to the position of a patrolling vehicle equipped with GPS receiver  114  may be provided to processor  110  to determine exact locations of the patrolling vehicle&#39;s path of travel at the time particular electric field measurements were received. GPS receiver  114  may be configured to provide a location reference including latitude, longitude, elevation, time and date about once per second so that the location is known to a reasonably high precision. GPS position data may be exported to a conventional GPS mapping software for utilization and then stored, for example, in memory component  116 , so that there is a stored precision location and time reference associated with the stored electric field measurements. Memory component  116  may additionally be utilized to store, temporarily or permanently, other data pertaining to electric field measurements, video images or any other data associated with the stray voltage detection process described and referenced herein. 
   Since apparatus  100  may be operated in urban/city environments where buildings and other obstacles distort and/or block signals from a GPS satellite system from reaching GPS receiver  114  via a direct path, GPS location information may have degraded accuracy, or may not be available. In those cases, wheel speed sensor  112  may be provided as a suitable substitute for highly accurate GPS location information, or may be utilized in conjunction therewith. 
   Thus, the GPS location data provides a record of the location at which each detected stray voltage anomaly was detected and the time thereof as may be desired for subsequent analysis, for example, for reviewing the location of the anomaly and identifying the emitting source in the patrolled environment. Since the peak of a response to a source of stray voltage can not be ascertained until after the patrolling vehicle has passed the source, the exact location of the source may not be observed until after the time at which it is detected (i.e. until after it is passed). While having this stray voltage and location data recorded is desirable and beneficial, in a typical service environment, e.g., on a city street, it is not practical to stop the patrolling vehicle carrying apparatus  100  each time a stray voltage is detected, or to back the vehicle up to ascertain the exact location at which the detection took place. 
   Transceiver component  118  may be configured to transmit and receive data transmissions to and from remote transceivers. Transceiver component  118  may be transceivers of the type that are compatible with Wi-Fi standard IEEE 802.11, BLUETOOTH™ enabled, a combination of local area network (LAN), wide area network (WAN), wireless area network (WLAN), personal area network (PAN) standards or any other suitable combination of communication means to permit robust wireless transmission of data. For example, transceiver component  118  may be a BLUETOOTH™ enabled device, thereby providing a means for communicating stray voltage related information between mobile apparatus  100  and a remote device, such as a personal digital assistants (PDAs), cellular phones, notebook and desktop computers, printers, digital cameras or any other suitable electronic device, via a secured short-range radio frequency. Thereafter, a utility member equipped with the remote device configured to receive the stray voltage related communication may be dispatched to a site determined to have a potential stray voltage anomaly for purposes of neutralizing the anomaly. It should be noted that the aforementioned are provided merely as exemplary means for wireless transmission of stray voltage related data. Other suitable wireless transmission and receiving means may be employed in the present invention. 
   An optional laptop computer (not shown) or other suitable computing system having a display provides GUI  120  for an operator to control the operation of apparatus  100 , particularly measurement and processing components associated with sensor probes  104 , and to monitor electric field data as measured. For example, an operator may adjust the values of the constants and scaling factors utilized in the detection and averaging processing for producing an audible alarm (described in detail below). The laptop computer may also provide a convenient means for storing a record or log of the measured field and location (GPS) data for subsequent review and/or analysis, as might be desired for determining when and where a stray voltage anomaly existed. 
   GUI  120  receives data, directly or indirectly, from various components described in conjunction with apparatus  100  and, accordingly, displays them to the operator for purposes of controlling and monitoring the detection of stray voltage anomalies present in patrolled areas. GUI  120  is a video based interface having a video display  122 . The data provided to GUI  120  provides the interface operator with an opportunity to visually monitor and analyze incoming data measured by a stray voltage detection system on video display  122 . 
     FIGS. 2-13  illustrate exemplary displays that may be provided on video display  122  of GUI  120  for monitoring and controlling the operation of apparatus  100 . As previously described, GUI  120  is provided on a computer, preferably a laptop computer for purposes of mobility. Upon start up of GUI  120  of apparatus  100 , for example, by selecting or clicking an icon displayed on the “desktop” provided on a monitor display of a computer, a computer program for providing GUI  120  will initialize a main display  200 , as illustrated in  FIG. 2 . Main display  200  provides an interface user with a real-time monitoring environment of the area being patrolled for stray voltage anomalies. Main display  200  may be comprised of a video display  202  and a control panel  204 . Real-time electric field measurements and video frames of the patrolled environment may be provided in video display  202 , which is supplemented with a graphical plot having an x-axis  202   x  indicative of the linear distance traveled by the patrol vehicle versus a y-axis  202   y  indicative of the signal strength of the measured electric field associated with various locations of the patrol vehicle. In order to initiate the detection and monitoring system of apparatus  100 , the interface user may select a run command option  206  provided on display  200 . 
   Run command option  206 , when selected, will prompt for information to be entered in an initial identification screen. The initial identification screen may be, for example, system login display  300  of  FIG. 3 . System login display  300  may request an the interface operator to provide a username in field  302 , a patrol vehicle name in field  304  and a patrol vehicle number in field  306  for purposes of authorizing access to the operational and monitoring controls of apparatus  100 . When the required information has been provided by the interface operator in fields  302 ,  304  and  306 , the interface operator may then select login command option  308  to proceed with system verification of authorized access to apparatus  100 . Similarly, the interface operator may select cancel command option  310  to terminate login procedures for apparatus  100 . 
   Upon a successful login at display  300 , data sampling is initiated and main display  200  is populated with sensor data, as illustrated in the main display of  FIG. 4 . Sensor data is provided on video display  202 , which may be provided in a split screen format for displaying multiple video image frames (one from each camera). A split screen view  402  may display video image frames received from camera  108   a , while a split screen view  404  may display corresponding video image frames received from camera  108   b , or vice versa. For example, a patrol vehicle may be equipped with cameras  108   a  and  108   b  positioned on opposing sides for providing corresponding video image frames from both sides of the patrol vehicles path of travel. Although main display  200  of  FIG. 4  is shown with two split screens  402  and  404 , additional split screens may be incorporated into video display  202  for an apparatus utilizing more than two cameras. 
   Three plot lines, a raw electrical field measurement plot  406 , an adaptive threshold plot  408  set relative to the local ambient or background noise level and a smoothed plot  410  are provided in conjunction with the graphical plot overlaid on the video image frames displayed on video display  202 . Adaptive threshold plot  408  is generated from data gathered before and after the raw voltage was sensed by sensor probes  104   a - 104   c . Smoothed plot  410  is a smoothed version of plot  406  that has been filtered to remove spurious content. A potential stray voltage is indicated when smoothed plot  410  exceeds adaptive threshold plot  408 . 
   Control panel  204  of main display  200  provides the interface operator with a plurality of monitoring and control options. An enlarged view of control panel  204 , as illustrated in  FIG. 4 , is provided and described in connection with  FIG. 5 . Control panel  204  may include a system monitor indicator  502 , an audio threshold indicator  504  and an audio snooze indicator  506 . In addition, a clear command option  508 , a suspend command option  510 , a preferences command option  512 , an event capture command option  514  and a stop command option  516  are provided to the interface operator in control panel  204 . Control panel  204  may also provide information in a latitude display  518 , a longitude display  519 , an address display  520 , a signal strength display  522 , a speed display  524  and a time stamp display  526 . 
   Indicators  502 ,  504  and  506  may be visual indicators, configured to change color or blink upon satisfaction of preprogrammed criteria. System monitor indicator  502  may be a green color when operating within system specifications. When a problem is detected in connection with GUI  120 , system monitor indicator  502  may turn yellow to notify the interface operator that their exists a problem, such as, lack of a GPS signal. In this case, no latitude, longitude or address information may be shown, respectively, in displays  518 ,  519  and  520 . Another potential trigger indicative of a problem is lack of video or electric field measurement data, wherein there would be no video image frame or measurement readings on video display  202 . Other potential problems that may trigger indicator  502  may be depleted disk space for recording captured events (described in detail below) or loss of communication between processor  110  and GUI  120 . 
   Generation of an audible tone output signal having a pitch that is proportional to the signal strength of the measured electric field may be provided as a tool in conjunction with the monitoring capabilities provided in GUI  120  to aid the interface operator in determining the source and potential danger of stray voltage anomalies. An audio threshold value that is indicative of the minimum voltage level required to trigger an audible notification tone is desired. For example, an optimum audio alert value for identifying stray voltage anomalies, while minimizing the number of false detections, may be preset as a default value. Default settings may be represented by audio threshold indicator  504  being, for example, a green color. 
   However, the interface operator may adjust the default threshold settings provided in connection with the audible notification tone if too much noise is being picked up. By selecting preferences command option  512  provided on control panel  204 , the interface operator could be provided with a preferences display  600 , as illustrated in  FIG. 6 , for modifying values associated with the audible tone. Therein, the interface operator could raise the threshold value, using audio threshold increase button  602  and decrease button  604 , to minimize or eliminate false audible tones being generated due to a noisy environment in a patrolled environment. Any changes made to the default audible threshold value in preferences display  600  may be represented by audible threshold indicator  504  on control panel  204  turning yellow. The change in color informs the interface operator that the audible notification tone is operating according to user defined values, not system defined default values. 
   Additional features that may be provided in preferences display  600  of  FIG. 6 , may be an audio snooze time option  606 , an x-axis toggle switch  608 , a y-axis toggle switch  610 , a trace option  614  and a DSP string option  616 . Audio snooze time option  606  specifies in seconds how long audio alerts are suspended when a snooze button  506  is pushed. Snooze button  506  may be green when default values are provided in the display of snooze time option  606  of preferences display  600 . However, similar to audio threshold indicator  504 , snooze button  506  may also include a color indicator that changes, for example, to yellow when the default snooze time has been changed in preferences display  600 . Toggle switches  608  and  610  permit the interface operator to adjust, respectively, the scale used in x-axis  202   x , which measures in feet the distance traveled since the last event capture, and y-axis  202   y , which measures in decibels the electric field signal strength, on video display  202 . Trace option  614 , when selected, allows for the logarithmic scaling of all y-axis  202  values in order to ensure that values are easily readable and that entire plot lines appear within video display  202  of main display  200 . DSP string option  616  may be provided as a means for displaying processing related data, when selected, to troubleshooting apparatus  100 . 
   Default values for system preferences identified in display  600  may be restored by selecting a restore defaults command option  618 . Otherwise defined preferences may be saved and executed by selecting an “OK” command option  620 . Alternatively, if the interface operator decides not to make any changes, then a “CANCEL” command option  622  may be selected. Selection of either command option  620  or  622  will return the interface operator to display  200 . 
   As the patrol vehicle traverses through an environment, streaming synchronized data of the electric field strength overlaid on the corresponding video frames of the scene being traversed at the time of measurement may be displayed to the interface operator on video display  202  of main display  200 . In addition, corresponding latitude and longitude information related to the patrolling vehicle is received by GPS receiver  114  and provided, respectively, to display fields  518  and  519 . An address corresponding to the latitude and longitude readings provided in display fields  518  and  519  may also be provided in display field  520 . A signal strength value may be provided in display field  522 . The speed of the patrol vehicle may be presented in display field  524 , along with a current data and time stamp in display field  526 . The interface operator may temporarily suspend data sampling at any time by selecting a suspend command option  510 , clear received data by selecting a clear command option  508  or exit GUI  120  system entirely by selecting a stop command option  516  provided on control panel  204  of main display  200 . 
   As the interface operator monitors the incoming streaming data on video display  202 , he/she is also presented with a variable-pitch alert that is configured for alerting the interface operator of detected fluctuations and/or spikes in measured electric field readings that exceed a defined threshold. Therefore, when a potential anomaly is detected, represented for example by a rise-peak-fall in the alert pitch, a corresponding visual spike in raw voltage plot  406 , a high signal strength value in display field  522  or a combination thereof, interface operator may select an event capture command option  514  for purposes of gathering additional information to review the potentially detected stray voltage anomaly. Therefore, when the interface operator selects event capture command option  514  on control panel  204  of main display  200 , he/she may be presented with a data collection display  700  and a event capture display  800  illustrated, respectively, in  FIGS. 7 and 8 . Data collection display  700  prompts the interface operator to continue driving the patrol vehicle for a predefined distance (e.g., an additional 40 feet after selection of event capture command option  514 ) in order to collect enough data sampling information to fully analyze the background noise associated with the captured event. A progress bar  702  may be provided in display  700  to inform the interface user of the remaining distance of travel required. Upon completion of the additional information collection process, represented by progress bar  702 , the interface operator may stop the collection of streaming data by GUI  120  and proceed to event capture display  800  for analyzing the captured event. The collection of streaming data may be stopped or paused by stopping the patrol vehicle. Alternatively, collection of additional information pertaining to the captured event may be optionally terminated earlier, through selection of a cancel command option  704 , to permit the interface operator to proceed to review the captured event on event capture display  800  without collection of additional information. 
   After driving the additional distance prompted by display  700  and stopping the patrol vehicle, processing of data related to the event capture may be processed (e.g. by processor  110 ) and a second distinctive alert tone (e.g., a chime-like sound) may be presented to the interface operator if it is determined that the processed captured measurement is not a false alarm. Thereupon, the interface operator could further examine the potential detected anomaly in event capture display  800 , as illustrated in  FIG. 8 . Similar to main display  200 , event capture display  800  provides a video display  802  and a playback control panel  804 . Scene scroll tabs  803   a  and  803   b  may be provided on opposing sides of display  802  to permit the interface operator to view captured video images and their corresponding electric field measurements throughout various positions traversed by the patrol vehicle. Event capture display  800  may also provide a pinpoint indicator  801  that may be positioned on any part of the video display  802  to display data and video for a different location. Data displayed in playback control panel  804  (to be described below) corresponds to the applied position of indicator  801 . For example, if the interface operator would like to view measurement and video data associated with a position 225 feet prior in motion, the interface operator could use scene scroll tabs  803   a  and  803   b  to move pinpoint indicator  801  to the desired location on video display  802 . 
   Event capture display  800  allows the interface operator to more closely examine potentially detected anomalies by providing playback analysis of the captured event. More specifically, the interface operator may compare raw voltage plot  406  and adaptive threshold plot  408  to assist in identifying the object displayed in the corresponding image frame that is most likely to be the source of the anomaly. In event capture display  800 , the three plot lines may be aligned to permit the interface operator to look for points where smoothed plot  410  exceeds adaptive threshold plot  408 . This indicates that there exists a spike above the averaged background noise and, therefore, the existence of an anomaly. 
   Enlarged views of a detected stray voltage anomaly as it may be provided on video display  802  of event capture display  800  of  FIG. 8  is illustrated in conjunction with  FIGS. 9-10 . In  FIG. 9 , pinpoint indicator  801  is positioned near the peak of spike in raw voltage plot  406 . All related sensor data related to this particular position is provided to the interface operator on playback control panel  804 . As can be seen near the spike in raw voltage plot  406 , smoothed plot  410  exceeds adaptive threshold plot  408 , indicative of a potentially dangerous anomaly in the captured scene. When pinpoint indicator  801  is positioned over the peak of a spike, the object most centered in a video frame on video display  802  is likely the source of the detected anomaly. An isolated enlarged view, as illustrated in  FIG. 10 , of the video image frame shown on video display  802  of event capture display  800  may be provided, wherein it can be seen that an object  1000  most centered in the video frame is likely the source of the detected anomaly. The video image frame may be isolated and enlarged by selecting a full screen command option  1106  ( FIG. 11 ) from playback control panel  804 . 
   An enlarged view of event capture control panel  804  is illustrated in  FIG. 11 . Event capture control panel  804  is comprised of a play command option  1102 , a pause command option  1104 , a full screen command option  1106 , a preferences option  1108  and a main display option  1110 . Play command option  1102  may allow the interface operator to play a video clip selected from a saved events section  1300 . Similarly pause command option  1104  may allow the interface operator to pause playback of the video clip selected from saved events section  1300 . Full screen command option  1106  may allow the interface operator to toggle between full-sized video images and regular-sized video images provided on display  802 . Preferences command option  1108  may provide the interface operator with additional playback and review options not shown on playback control panel  804 . For example, command option  1108 , when selected, may provide preferences related to wireless communication of captured events to dispatch a remote crew. Main display option  1110  may allow the interface operator to return to main display  200 . A disable plotting option  1112  may also be provided, wherein the plots may be removed for a clearer view of scene objects displayed on video display  802  when option  1112  is selected. 
   Once a detected stray voltage anomaly has been confirmed by the interface operator and object  1000 , for example, has been determined to be the likely source of the anomaly, the interface operator may then proceed to record object related information in an objects section  1200  of playback control panel  804 . An environmental object or infrastructure name may be listed in a predefined objects scroll menu  1202  or may be defined by the interface operator using an object identification field  1204 . The interface operator may then add the object identified in menu  1202  or field  1204  to a selected object field  1208  using, respectively, an add command option  1206  or an add command option  1203 . An added object identified in field  1208  may also be removed by selecting a remove command option  1207 . Additional notes, comments and instructions may be provided by the interface operator using a comments field  1210 . For example, the interface operator may identify a lamp post, in field  1208 , as the potential source of a detected stray voltage anomaly and instruct, in field  1210 , the need for a utility crew to be dispatched immediately to the site to neutralize the source. In addition, GUI  120  is configured so that if multiple objects are determined to be present in a scene where an anomaly was detected, the interface operator may identify the multiple objects in field  1208 . The interface operator may then select a save event command option  1114  to record the identified object source of the anomaly, associated comments regarding the anomaly and anomaly location information  1116  for future reference and analysis of the captured anomaly event. Thereafter, the interface operator may return to main display  200 , via command option  1110 , and restart movement of the patrol vehicle to restart data sampling of the scene being traversed. 
   Captured events that have been previously saved by the interface operator may be viewed by selecting a saved event file from an events listing  1302  available in section  1300  of playback control panel  804 . To open a saved event provided in listing  1302 , the interface operator, or any other applicable user, may select the desired event and then select a load event command option  1304 . When the desired event is loaded, display  800  is populated with all data related to the selected event (e.g., location information, object identification, comments, captured video image frame and corresponding measurement data). To play the video associated with a loaded event, the interface operator may move the pinpoint indicator  801  to the desired starting location on video display  802  in which he/she wishes to begin viewing and select play command option  1102 . 
   Information that has been populated, for example, into section  1200  may be edited. For instance, if it is determined that an object previously identified as the source of a stray voltage anomaly is not indeed the source of the anomaly, field  1208  may be edited using commands  1206  and  1207  to, respectively, add a new source and remove the inaccurate source. Once changes have been made, the interface operator may select an update command option  1306  to have the new information saved in connection with the previously saved event. 
   When an event is saved, apparatus  100  may be configured to generate a database entry for the saved event and create separate files for video and corresponding sensor related data. For example, apparatus  100  may be configured to create an AVI file for storing video images and an XML file for storing all other sensor related data. These files may be saved on a hard disk (e.g., memory component  116 ) and retrieved when the corresponding event is selected and loaded using playback control panel  804  on event capture display  800 . If it is determined that saved events are no longer needed or have been archived elsewhere, or alternatively, if additional storage space is needed in apparatus  100 , the interface operator may delete command options  1308  and  1310  provided on section  1300  of playback control panel  804 . 
   An illustrative depiction of the general steps employed in use of VGUI  120  of apparatus  100  for monitoring and controlling the detection of a stray voltage anomaly is described with reference to the flowchart of  FIG. 14 . As previously described, the monitoring of streaming data displayed on video display  122  of GUI  120  is initiated, at step  1402 , by providing user login information at step  1404 . If the login information provided at display  300  of  FIG. 3  is determined at step  1406  to be for an authorized user, then VGUI  120  may begin to sample data and provide a visual output of streaming data, at step  1408 , on main display  200 , which may be driven by movement of the patrol vehicle equipped with apparatus  100 . 
   Upon detection of a stary voltage anomaly at step  1410 . GUI  120  of apparatus  100  may audibly, via a variable-pitched alert tone at step  1412 , and visually, via a spike in plots provided on graphical video display  202 , prompt the interface operator. When initial detection of a potential anomaly is detected at step  1410 , interface operator may decide to capture the event at step  1414  by selecting event capture command option  514  provided on control panel  204  of main display  200 . In response to the user initiated instruction to capture an event, additional processing may be executed to collect additional information about the captured event and an additional alert notification may be provided to the interface operator at step  1416 , indicating to the interface operator that the subsequent processing of the captured event is likely a stray voltage anomaly. 
   Playback controls are provided to the interface operator, at step  1418 , via control panel  804  on event capture display  800  of  FIG. 8 . After the interface operator has had an opportunity to review information related to the captured event, as well as identify the source emitting the stray voltage anomaly at step  1422 , he/she may record the event at step  1420 . Thereafter, the interface operator may elect to resume data sampling of the area being patrolled at step  1424 , thereby reinitiating the receipt of streaming data at main display  200 . GUI  120  may go into a standby mode, at step  1426 , if no action is taken after a predetermined amount of time or, alternatively, if the interface operator elects to suspend data sampling by selecting, e.g., suspend command option  510  on control panel  204  of main display  200 . 
   One skilled in the art will appreciate that the present invention can be practiced by other than the described embodiments, which are presented for purposes of illustration and not by way of limitation, and the present invention is limited only by the claims that follow.