Abstract:
A system and method is described for a controlled electrified fish barrier that induces a potential field in a body of water with an electric field generator, a control system, and an object detection system, so that when the anode and cathode of the electric field generator are inserted in a body of water, and the object detection system detects an object, the object detection system electrically signals the control system; and in response the control system electrically adjusts the electric field generator.

Description:
RELATED APPLICATIONS 
       [0001]    This application claims the benefit of U.S. Provisional Application No. 61/178,641; filed May 15, 2009, the contents herein incorporated into this application by reference. 
     
    
     BACKGROUND 
       [0002]    The present inventive subject matter relates to the controlled electrification of fish barriers in general and the activation and control of barriers when certain objects are present in the water. 
         [0003]    The effect of electric currents on fish are well known in the prior art and especially in the creation and implementation of electrified fish barriers. U.S. Pat. No. 5,445,111 (Aug. 29, 1995) to Smith (hereinafter “Smith patent”), which is incorporated herein in its entirety by reference, describes a system where electrodes are configured in a curtain array and/or a picket fence arrangement. As described in the Smith patent, the energized electric field in the water creates a electrical barrier that guides the fish to a desired area (typically a fish ladder) during the period of fish migrations. Electrical barriers are generally more effective at fish entrainment or deterrence, than alternate methods, such as mechanical barriers or by chemical poisoning. 
         [0004]    Despite the inherent advantages of electrical fish barriers, there are certain situations in which the electrically generated field needs to be increased, decreased, or eliminated due to the presence of objects proximate to the barrier. For example, in certain situations, a vessel with a conductive hull may be present in the vicinity of the electrical fish barrier. The presence of a vessel will modify the electrical field requiring either an increase or a decrease in the potential difference to maintain the same electrical field. In other situations, there may be swimmers in the vicinity of the electrical field. In this situation the electrical field will also have to be modified to reduce any current effects on the swimmers. 
         [0005]    Therefore, what is desired is an apparatus to detect and quantify objects located in the vicinity of an electrical barrier and modify the electrical barrier in response to the measured characteristics of that object. 
       SUMMARY 
       [0006]    The present inventive subject matter overcomes problems in the prior art by having a controlled electrified fish barrier that induces a potential field in a body of water having an electric field generator, the electric field generator having an anode and cathode, and a control system, the control system electrically connected to the electric field generator; and an object detection system, the object detection system electrically connected to the control system; so that when the anode and cathode are inserted in a body of water, and the object detection system detects an object, the object detection system electrically signals the control system; and in response the control system electrically adjusts the electric field generator. The controlled electrified fish barrier also has an object detection system with an analog to digital (A/D) converter; a classifier, the classifier electrically connected to the Analog to Digital converter; a classifier-object database, the classifier-object database electrically connected to the classifier; and the classifier-object database further comprising: a data signature column and an output object column; so that when an analog electrical signal is received by the analog to digital converter and converted into a data signature, and the data signature is programmatically matched to produce an output object, such that the generated output object modifies the electric field barrier. The controlled electrified fish barrier also has an Analog to Digital Converter is a sonar system. The controlled electrified fish barrier of where the sonar system is a split-beam sonar. The controlled electrified fish barrier where the Analog to Digital Converter is a optical system. The controlled electrified fish barrier of where the Analog to Digital Converter is a wake detection system. The controlled electrified fish barrier where the control system has an electrical field that is adjustable. The controlled electrified fish barrier where the control system produces an electrical field in the water from 0.1 V/cm to 10 V/cm. 
         [0007]    A method for controlling an electrical field in a body of water having the steps of, obtaining an electric field generator, wherein the electric field generator has an anode and a cathode, immersing the anode and cathode in a body of water; connecting a control system to the electric field generator, the control system capable of modifying the electric field generator; connecting an object detection system to the control system, the object detection system electrically connected to the control system, detecting an object in the body; and, adjusting the electric field by the control system in response to the object These and other embodiments are described in more detail in the following detailed descriptions and the figures. 
         [0008]    The foregoing is not intended to be an exhaustive list of embodiments and features of the present inventive subject matter. Persons skilled in the art are capable of appreciating other embodiments and features from the following detailed description in conjunction with the drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0009]      FIG. 1  is a top view of the barrier system 
           [0010]      FIG. 2  is a flowchart of the operation of the barrier system. 
           [0011]      FIG. 3  is a functional block diagram of the object detection system. 
       
    
    
     LIST OF REFERENCE CHARACTERS 
       [0000]    
       
           110 —Electric Field Generator 
           112 —Anode 
           114 —Cathode 
           120 —River 
           122 —Downstream Water Flow 
           130 —Object Detection System 
           132 ,  134 —Object Detectors 
           136 —Detection-Control Link 
           140 —Control System 
           142 —Control-Barrier Link 
           150 —Boat 
           160 —Person 
           170 —Fish 
           200 —Flowchart 
           210 —Program is started 
           220 —Initialized 
           230 —Monitors 
           240 —Detected 
           250 —Adjusted 
           260 —Object is not present 
           270 —Reset 
           310 —classifier-object database 
           320 —A/D converter, 
           330 —Classifier, 
       
     
       DETAILED DESCRIPTION 
       [0036]    Representative embodiments according to the inventive subject matter are shown in  FIGS. 1-3  wherein similar features share common reference numerals. 
         [0037]    The term “fish” generally refers to the should not be limited to only such fish, but can also include any animal in a body of water, such as, an ocean, stream, or lake, such as pinnipeds, crustaceans, and/or humans. 
         [0038]    The term “river” is generally refers to a freshwater body of water that flows from land to the ocean, but the term can also include any flowing body of water, including, but not limited to, tidal zones, flows between estuaries, flows to tributaries, and oceanic water flows. 
         [0039]    Now referring to  FIG. 1 , which illustrates the preferred embodiment of the inventive subject matter; a controllable electric field barrier system  100  (hereinafter “barrier system”). The barrier system  100  has an electric field generator  110 , and anode  112 , and the cathode  114 . The anode  112  and the cathode  114  are immersed in water (e.g. the River  120  or Stream) and when the anode and cathode are electrified an electric field is formed between the anode  112  and the cathode  114 . This electric field affects boats  150  and people  160  when they are in the proximity of the electric field. The electric field also has the effect of deterring fish  170  when an electric field is present. 
         [0040]    The electric field generator  110  generates an electric field between the anode  112  and the cathode  114 . The intensity of the electric field created by the electric field generator  110  is dependent on a number of environmental factors in the river  120 . First, the field is dependent on the width of the river  120 . Second, the field is dependent on the spacing between the anode  112  and the cathode  114 . Third, the electric field is dependent on the conductivity of the water. For example, river water generally has a lower conductivity than sea water and as a consequence the electric field generator  110  in connection with sea water will require greater electrical power to produce the same voltage gradient than in river water. 
         [0041]    As discussed, the size and capacity of the electric field generator  110  can be determined based on the configuration of the barrier. A typical barrier may be powered by a 1500 watt pulsator, such as the Smith-Root™ BP-1.5-POW Pulsator (see http://www.smith-root.com/barriers/equipment/). Larger barriers would require correspondingly larger power supplies and/or multiple units of the aforementioned pulsator (e.g. electrical generator). Electrodes may also be constructed from conductive materials, such as, steel, iron, rebar, or similar materials that have high conductivity and are durable in river water and/or sea water. 
         [0042]    The operation of the electric field barrier system  100  involves three subsystems. An object detection system  130  having the subcomponents of object detectors  132 ,  134 , and a Detection-Control Link  136 . The object detectors  132 ,  134  are configured to detect an object in the water. The object detectors  132 ,  134  may utilize active sonar technology, passive sonar technology, visual technology (e.g. optical sensors), and/or splash sensors. The object detectors  132 , 134  produce electronic signatures that are digitized by the object detection system  130 . During operation, the object detection system  130  outputs an electronic signature that corresponds to the object present in the water. A typical object may be a boat  150  or a person  160 . The example of a boat  150  or a person  160  is for representative purposes only any equivalent object may have its own unique signature. 
         [0043]    Now referring to the flowchart  200  of the control system for the barrier system as shown in  FIG. 2 . When the program is started  210  the programs and target database  310  (see  FIG. 3 ) are initialized  220 . The system then monitors  230  the water are for objects, such as a boat  150  and/or a person  160  that may fall into the river  120 . When an object  150 , 160  is detected  240 , the electrical field is adjusted  250 . The adjustment of the electrical field is performed by sending a signal to the barrier electrifier  110 . This adjustment  250  of the electrical field occurs until the object is not present  260 . When the object is not present the electrical field is reset  270  to its previous state. 
         [0044]    The term “adjustment of the electrical field” may involve increasing and/or decreasing the electrical field relative to the normal settings of the electric field. For example, if the barrier is design to entrain fish, a electrical field setting of 1 V/cm may be the setting for the normal operational characteristics of the field. Alternately, to deter pinnipeds an electrical field setting of 0.1 V/cm may be the setting for the normal operational characteristics of the field. 
         [0045]    Now referring to  FIG. 3  which illustrates the object detection system  130 . The components of the object detection system  130  is an A/D converter  320 , a classifier  330 , and the detection-control link  136 . The classifier  330  is connected to the classifier-object database  310 . 
         [0046]    The A/D converter  320  converts signals using devices that are well known in the arts. For example, a sonar signal will output an A/D signature that is characteristic of an echo. Representative systems that can monitor and characterize the sonar signal consist of the SciFish 2100 (Attached as Appendix A). 
         [0047]    Other detection systems would generate A/D signals would have different characteristics. For example, a “splash detector” would sense that an object fell in the water. The perturbation of the water surface would have a characteristic that could be classified and recognized. These detection systems may consist of simple level detectors that are positioned on the edge of the water surface (e.g. to measure the “ripple” created by the water when an object impacts the surface.). Alternately, the system may consist of optical detectors that measure a change in the reflection of the surface as a consequence of an object being in the water. 
         [0048]    The classification of A/D signals is dependent on the creation of a signature database. Now referring to  FIG. 3A  which depicts some of the functional elements of this database. A list of data signatures  312  is stored in a row with a corresponding list of output objects  314 . When a data signature  312  is pattern matched against the output object  314 . The output object  314  consists of an electrical profile consistent with the type of action to be taken based on the data signature  312 . 
         [0049]    For example, if the data signature  312  indicates that a person is in the body of water proximate to the anode  112  and the cathode  114 , then the output object  314  may be set to reduce the electrical field from operational strength to a minimal field. Alternately, a conductive ship may be passing between the anode  112  and cathode  114  which would require the output object  314  to modify the electrical profile to maintain the same electrical field strength in the water. 
         [0050]    Another example involving the data signatures  312  for individuals species of fish that are in the water and are proximate to the anode  112  and the cathode  114 . These signatures may represent migratory fish, young-of-year (YOY), invasive species, or other aquatic animals. The output object  314  will modify the electrical profile to adjust the electrical field strength in the water in response to the particular type of fish. 
         [0051]    Persons skilled in the art will recognize that many modifications and variations are possible in the details, materials, and arrangements of the parts and actions which have been described and illustrated in order to explain the nature of this inventive concept and that such modifications and variations do not depart from the spirit and scope of the teachings and claims contained therein. 
         [0052]    All patent and non-patent literature cited herein is hereby incorporated by references in its entirety for all purposes.