Abstract:
A system for tracking a fleeing vehicle, using optional remote sensing to identify a payload contained in the vehicle or asset, and an optional device disabling the fleeing vehicle via disrupting the vehicle&#39;s onboard computer or electrical system. The system includes a tracking device or carrier containing tracking components, sensing equipment, and the vehicle disabling device. A launcher of the tracking device may be handheld or vehicle mounted, and may use high pressure gas or another propellant to launch the projectile at a fleeing vehicle. The electronics package may include tracking hardware, sensing hardware, and the vehicle disabling hardware. Once launched and affixed to the suspect vehicle or stationary target, the vehicle&#39;s location can be tracked while sensors detecting any trace elements of explosives, IED (Improvised Explosive Device) materials, WMD (Weapons of Mass Destruction), biochemical materials, drugs, or any form of contraband can be monitored from a safe distance. In the case of a vehicle or moving target, the vehicle may then be disabled from a safe distance if sensors detect any abnormality in the targeted vehicle&#39;s payload.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is related to and claims the benefit of U.S. Provisional Patent Application Ser. No. 60/997,677, filed on Oct. 4, 2007, titled, “Method and system for tagging, tracking, remote sensing, and disabling a vehicle,” which is hereby incorporated by reference. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention is directed to tracking, sensing and disablement system for a moving or fixed target, typically, but not limited to a fleeing vehicle. Specifically, the present invention is directed to a system which remotely tracks a vehicle with a location module, scans the vehicle for contraband substances and/or electronically disables the vehicle. 
       BACKGROUND OF THE INVENTION 
       [0003]    Terrorist attacks around the world have reshaped ways of behavior, including the way governments view threats to freedom nationally and internationally. Anti-terrorism intelligence is a high priority for many nations. Being able to simply gather conventional intelligence is not good enough. These national threats use tactics that demand real-time tracking and information gathering capabilities which would include an arsenal of remote sensing and intelligence gathering instruments to identify and engage these threats to our freedom. The timely handling of this critical data therefore ensures a quick response from government agencies and municipalities that deploy these tools. The goal is to detect and thwart attempts to attack from these elements that range from explosive, biochemical, nuclear, or other means. 
         [0004]    Technical innovations through aggressive funding from both the government and private sectors has fueled the remote sensing industry to miniaturize these vital components to our national security and make them readily available in the commercial market 
         [0005]    The need to be able to know the whereabouts of suspicious vehicles/assets and remotely test them for contraband would provide law enforcement and homeland security with added measures to proactively search for these threats and engage them if necessary. 
         [0006]    The present invention provides a method and system to “tag” a fleeing or stationary “target,” such as a vehicle, by attaching a tracking device, a sensor device/s, and/or a vehicle disabling system to the target from a distance and then monitoring the location of that target without constant visual contact, thereby minimizing the risk to bystanders and the individuals involved in the pursuit. 
         [0007]    The present invention additionally provides a method for disabling a vehicle either remotely or automatically upon the vehicle achieving a predetermined condition such as dropping below a selected speed. 
         [0008]    The present invention further provides a method for scanning a vehicle or fixed target for trace elements of interest including, but not limited to, explosives, IEDs, Weapons of Mass Destruction, and/or contraband. 
       BRIEF SUMMARY OF THE INVENTION 
       [0009]    Accordingly, an embodiment of the present invention is a method for tagging and tracking a target vehicle for the purpose of gathering sensor based information and deploying an electrical charge to incapacitate the vehicle, the method comprising providing a launcher having at least one barrel, a carrier having an electronics package, and sufficient propellant to launch the carrier from the launcher in order to affix the carrier to a fixed or moving target at a predetermined range, the carrier electronics package having a tracking system, at least one sensor, and a vehicle stopping system; sighting the target vehicle using a target acquisition device; launching the carrier from the launcher towards the target vehicle; attaching the carrier, with the electronics package within the carrier, to the target vehicle, thereby tagging the target vehicle; and causing a tracking signal to be emitted from the tracking system. Optionally, this method may include the steps of receiving the tracking signal emitted by the tracking means, the tracking signal including information identifying the electronics package, location, and any sensor data; converting the received tracking signal into an image of the tagged target vehicle and sensor data; and determining the need to stop the vehicle based on target vehicle characteristics determined from the tracking signal. This may include displaying the image on a display system, the image representing the location of the tagged target vehicle and sensor data identifying a payload of the vehicle; and providing a remote actuator for remotely stopping the vehicle using the vehicle stopping system. 
         [0010]    Alternatively, the method may include receiving the tracking signal and sensor data at a static location using a computer system selected from the group of static computer, networked computer, mobile computer, handheld computing device, and cellular phone. The target vehicle may vary widely, including items or vehicles selected from the group of an automobile, a trailer, a trailer attached to a tractor trailer truck, a boat, an aircraft, a military vehicle, a motorcycle, an off terrain vehicle. Of course, vehicles that are stationary should be included within the meaning. 
         [0011]    As an additional option, the method may involve a tracking signal comprises information from a global positioning system, such as Global Positioning Satellite, etc. 
         [0012]    An embodiment of the present invention is a tagging device for tagging a target vehicle, the tagging device comprising a tracking chip having a microprocessor, a power source, and an emitting means for emitting a tracking signal, the tracking signal emitted being a unique representation of the tracking chip; a vehicle stopping technology; and an attachment means for attaching the tracking chip and vehicle stopping technology to the target vehicle, the attachment means containing the electronics package therein, such that when the attachment means attaches to the target vehicle, the electronics package contained therein is not damaged. Optionally, the attachment means is capable of adhering to the target vehicle, whether by adhesive, magnetic material, etc. The attachment means may optionally have an outer surface. 
         [0013]    Optionally, the electronics package may further comprise at least one sensor and a receiving means for receiving an arming signal, with an arming signal causing the electronics package to emit the tracking signal and to transmit sensor data. 
         [0014]    Another embodiment or aspect is a tracking system having a tracking device comprising a tracking chip having a microprocessor, an antenna, a power source, and an emitting system for emitting a tracking signal, the tracking signal emitted including a unique representation of the tracking chip; an attachment means for attaching the tracking chip to the target vehicle, the attachment means containing the tracking chip therein, such that when the attachment means attaches to the target vehicle, the electronics package contained therein is not damaged; a launching device having at least one barrel capable of receiving the tracking device, a sighting device, a rangefinder, a source of pressure to expel the tracking device from the barrel; a receiver system comprising a receiver capable of receiving the tracking signal and an interpretation device for interpreting the received tracking signal to identify the tracking chip and to indicate the location of the tracking chip such that when the tracking device is adhered to a target vehicle the tracking signal represents the location of the tagged target vehicle; a display in communication with the receiver system and responsive to the interpreted tracking signal from the receiver system so as to provide a visual image of the location of the target vehicle; and a controller system having a controller, an input device, and a transmitter, the controller system in communication with the receiver system, capable of actuating the tracking system. 
         [0015]    Optionally, the controller system may further comprise an actuator for arming the tracking device and a firing means for firing the tracking device, the actuator adapted, upon launching of a tracking device from the launching device, to cause the tracking device to emit the tracking signal. 
         [0016]    Another embodiment of this system is one wherein the tracking device further comprises at least one onboard data gathering sensor to detect substances, the sensor being in communication with the emitting system for inclusion of sensor data within the tracking signal; wherein the at least one onboard data gathering system is contained within the attachment means; wherein the interpretation device is adapted to interpret sensor data; and further wherein the display is in communication with the receiver system and responsive interpreted sensor data to provide a visual image of the sensor data. 
         [0017]    Another embodiment of this system is one wherein the tracking device further comprises a vehicle stopping device that discharges electricity to incapacitate the vehicle; wherein the vehicle stopping device is contained within the attachment means; wherein the controller system is further capable of transmitting a disabling signal to activate the vehicle disabling system in response to the receiver system receiving a tracking signal meeting a predetermined set of parameters or in response to a command received from the input device. 
         [0018]    An embodiment of the system for the present invention is for tagging, tracking, sensing data from, and disabling a target vehicle, the system comprising a tracking device comprising a tracking chip having a microprocessor, an antenna, a power source, and an emitting system for emitting a tracking signal, the tracking signal emitted including a unique representation of the tracking chip; at least one onboard data gathering sensor to detect substances, the sensor in communication with the emitting system for inclusion of sensor data within the tracking signal; a vehicle stopping device that discharges electricity to incapacitate the vehicle; an attachment means for attaching the tracking chip to the target vehicle, the attachment means containing the tracking chip, sensor, and vehicle stopping device therein, such that when the attachment means attaches to the target vehicle, the electronics package contained therein is not damaged; a launching device having at least one barrel capable of receiving the tracking device, a laser sighting device, a rangefinder, a source of pressure to expel the tracking device from the barrel; a receiver system comprising a receiver capable of receiving the tracking signal and an interpretation device for interpreting the received tracking signal and sensor data to identify the tracking chip and to indicate the location of the tracking chip such that when the tracking device is adhered to a target vehicle the tracking signal represents the location of the tagged target vehicle, and further for interpreting sensor data; a display in communication with the receiver system and responsive to the interpreted tracking signal and sensor data from the receiver system so as to provide a visual image of the location of the target vehicle and sensor data; and a controller system having a controller, an input device, and a transmitter, the controller system in communication with the receiver system, capable of transmitting a disabling signal to activate the vehicle disabling system in response to the receiver system receiving a tracking signal or sensor data meeting a predetermined set of parameters or in response to a command received from the input device. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS  
         [0019]      FIG. 1  is a drawing showing a perspective view of a police vehicle firing a tracking projectile, remote sensors and/or vehicle disabling device at a target vehicle; 
           [0020]      FIG. 2  is a drawing showing a side cut-away view of a tracking projectile launcher; 
           [0021]      FIG. 3  is a alternate representation of the launcher in a fixed or static mount position 
           [0022]      FIG. 4  is a drawing showing a top view of the launcher encased in the weatherproof box; 
           [0023]      FIG. 5  is a drawing showing a front view of the launcher; 
           [0024]      FIG. 6  is a drawing showing a police vehicle having the launcher mounted at various positions; 
           [0025]      FIG. 7  is a drawing showing a cut-away view of the tracking projectile; 
           [0026]      FIG. 8   a  is a perspective view of a handheld launcher; 
           [0027]      FIG. 8   b  is a front view of a handheld launcher; 
           [0028]      FIG. 8   c  is a cross-sectional view of an alternate embodiment of a tracking projectile as used in a handheld launcher; 
           [0029]      FIG. 9  is a cross-sectional view of an alternate embodiment of a tracking projectile as used in the present invention; 
           [0030]      FIG. 10  is a cross-sectional view of an alternate embodiment of a tracking projectile as used in the present invention; and 
           [0031]      FIG. 11  is a perspective view of an alternate embodiment of a tracking projectile as used in the present invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0032]    An aspect of embodiments of the present invention is to provide a method of “tagging” a target vehicle by attaching a tracking device, sensors and/or a vehicle disabling device to it from a distance and then monitoring the location of that target vehicle. The present application hereby incorporates by reference the following issued U.S. Patents, (1) U.S. Pat. No. 6,246,323, entitled “Method and System for Tracking a Vehicle” and (2) U.S. Pat. No. 6,650,283, entitled “Vehicular Tracking Device.” 
         [0033]    Another aspect is to enable the use of a launcher, either handheld or mounted on a vehicle, with single or multiple barrels, to launch a carrier using high pressure air, CO2, gunpowder, electricity, liquid, or solid fuel, or any other method of propulsion to drive the electronics package from the launcher to the stationary target or vehicle. 
         [0034]    Another aspect is to provide an apparatus that will cause the attachment to or tagging of a vehicle with a tracking device, sensors and/or vehicle disabling device such that the vehicle may be tracked, the sensors can transmit data concerning substances of interest and a fleeing vehicle may be disabled. 
         [0035]    Another aspect is to provide a device that will launch a tracking device from a pursuing vehicle, stationary vehicle, or fixed or mobile position. 
         [0036]    Another aspect is to provide a handheld device that will launch a tracking device, remote sensors, and/or vehicle disabling device towards a vehicle or stationary target. 
         [0037]    Another aspect is to provide a tracking system whereby the tagged vehicle can be tracked by at least one mobile pursuit vehicle or at least one remote location, or both. 
         [0038]    Another aspect is to be able to gather and process information from the sensors in a real-time fashion using an RF link to transmit an identification of the payload onboard the asset. The sensors can test for a wide variety of contraband to ascertain the threat level of the payload. 
         [0039]    Another aspect is to provide a means of arresting the vehicle through an electric charge that would bring the vehicle to a stop. The vehicle disabling device would be triggered from either the onboard chipset or from a remote location that communicates with the unit via the RF link or other suitable communication link. 
         [0040]    An embodiment of the present invention is capable of tracking, sensing and vehicle disablement system, the system having a launcher that shoots and attaches a projectile to a moving or fixed target, typically, but not limited to a fleeing vehicle. Specifically, the present invention is directed to a system which remotely tracks a vehicle with a location module, and optionally scans the vehicle for contraband substances and/or electronically disables the vehicle. 
         [0041]    In addition, the system of the present invention embodies a method of real-time tagging and tracking coupled with at least one data gathering sensors and/or a vehicle stopping system that consists of a launching device, a tracking device, sensing devices, a electromechanical, or electromagnetic vehicle disabling device, and a receiving device to monitor the location of the target and to communicate with the sensors and vehicle disabling device. 
         [0042]    Once a target has been tagged and the receiving device has determined the location of the target, the location may be displayed on mapping overlay software. The sensors may test the target for any evidence of explosives, biochemical substances, weapons of mass destruction (WMD), dirty bombs, drugs, or other substances or contraband of interest. 
         [0043]    Upon evaluating the need to disable the target of interest, the system can be commanded from a user input or interface on the receiving system to disable the vehicle by incorporating a vehicle stopping or disabling device that emits a power surge with enough energy to disable the target&#39;s electronic systems thus bringing the target to a stop if the target is in motion. The system may also be set to disable the vehicle when a particular set of parameters are met i.e. speed, location of the vehicle, geo-fencing, or upon the sensors detecting explosives, WMD, biochemical threats, or improvised explosive device (IED) material. 
         [0044]    The data gathering system may contain one or more onboard sensors for detecting trace elements of interest including, but not limited to, biochemical, explosives, IEDs, Weapons of Mass Destruction, dirty bombs, and/or contraband of any kind. The electronics package is equipped with video/audio surveillance components to aid in the detection of these trace elements. 
         [0045]    The GPS/A-GPS/RFID or other type of active or inertial location module coupled GSM/CDMA/iDen or other cell or RF communications means, antennas, power supply, adhesive or other means of attachment and a power generating module that are preferably coupled to create a vehicle stopping technology using electromagnetic discharge, electrical burst, or any method of discharging electricity to provide an arresting electric pulse, or discharge to the vehicle&#39;s electronic system whether tethered or un-tethered to the launching vehicle. 
         [0046]    The electronics package above may be fired from a vehicle mounted or handheld device, with the package achieving stabilized free flight and affixing to the vehicle. The launcher device powers the projectile to the target using methods such as high pressure air, CO2, gunpowder, electricity, liquid or solid fuel, primer, or any other method of propulsion to drive the electronics package from the launcher to the target vehicle. 
         [0047]    Either upon launching or when adhered to the target vehicle, the electronics package may transmit location-based and sensor-based data, via an RF link, for example, to a receiving system, which is preferably a data center that extrapolates the incoming data to monitor the vehicle&#39;s location. At the same time the RF link is being utilized to transmit data as a result of the sensor operations to detect any form of contraband substance that may be onboard the target vehicle/item of interest. 
         [0048]    Once it is deemed necessary to stop the target, the vehicle disabling device can be triggered in a variety of ways. The electrical discharge component may be controlled through, but not limited to, the RF link, or via a suitable communication link reading an optimum heading, speed, location, or advantageous parameter that automatically triggers the discharge to the vehicles electronic system. 
         [0049]    Alternatively, the discharge may be triggered remotely through a suitable communications link from a central or mobile location, deploying the electrical discharge to the vehicle&#39;s electronics thus incapacitating the potential threat. 
         [0050]    Referring now in detail to the drawings,  FIG. 1  shows a police vehicle  100  behind a target or suspect vehicle  102 . A tracking, sensing and vehicle disabling projectile  300  is fired from a launcher or gun  200  mounted preferably behind the grill  104  of the police car  100  and strikes the rear of the target vehicle  102 . The tracking, sensing, and vehicle disabling projectile  300  is fired at a velocity such that it shatters upon impact with the target vehicle  102 , as discussed in further detail herein. 
         [0051]      FIGS. 2-4  show the launcher  200  in greater detail. The launcher  200  is preferably, but not limited to, a pneumatic or CO2 gun, such as that commonly used with paintballs, and is modified to be placed behind the front grill of a police car. 
         [0052]      FIG. 2  shows the launcher  200  in a sealed box  202  that protects it from the environment and other natural conditions such as rain, snow and dirt. The top of the box  203  preferably has latches  204  and  206  which provide access to the inside of the box, so that the launcher  200  may be repaired, cleaned or otherwise maintained. The launcher  200  is preferably, but not limited to, supported by an articulating joint  208  which is controlled by a servo motor. The launcher  200  may have one or more barrels  211  which stay within the confines of the weatherproof box. A laser pointer/range finder  212  is placed on top of the barrels  211  to identify the path of the projectile and to mark the target. 
         [0053]    As the adjustable articulating joint  208  is moved down, the barrels  211  of the launcher  200  rotate upward. Similarly, if the adjustable articulating joint  208  is moved up, the barrels  211  of the gun rotate downward. In this way, the launcher  200  can be aimed at objects of different heights. The number of adjustments and manipulations necessary to operate the launcher  200  is limited to reduce the user&#39;s distractions. This makes the launcher  200  easier to operate in emergency situations when the user does not have the time to adjust multiple launcher  200  settings. Although this is the preferred embodiment of the invention, it should be understood that the invention could be modified to include multiple adjustment mechanisms for the launcher  200  without departing from the scope of the invention, to allow for greater versatility in its use. An example would be to have a universal servo mechanism at the rear of the launcher  200  so that its aim can be changed both up and down, and left and right. 
         [0054]      FIG. 3  shows the launcher  200  in an alternate embodiment as a static mount or fixed position launcher  200  having a single barrel that uses neither elevation nor windage adjustment. It is envisioned that the launcher  200  would be mounted in any of the locations specified, but not limited to the mounting position indicated in  FIG. 6 . The single barreled launcher  200  preferably has a magazine to feed projectiles  300  into the launcher  200 . 
         [0055]      FIG. 4  shows a picture of the top of the sealed box  202  with hinges  206  and  204  to keep the box  202  securely closed to protect the launcher  200  from the elements and to provide a method of cleaning, servicing, and otherwise maintaining the launcher  200 . 
         [0056]      FIG. 5  shows the front of the launcher  200  with the barrels  211  secured on the inside of the box  202 . The door  502  is preferably secured to the front of the weatherproof box  202  with hinges  501  and  503  that hold the watertight door  502  to the front of the weatherproof box  202 . 
         [0057]      FIG. 6  shows several other possible locations for the launcher  200 , such as on or under the hood of a car  702 , on the side of a car  704 , or on the roof of a car  706 . These embodiments are provided for illustrative purposes and are not meant to limit the scope of the invention to the locations shown in  FIG. 6 . It will be apparent to one skilled in the art that modifications and variations may be made as to the mounting location of the launcher  200  without departing from the scope of the invention. 
         [0058]      FIG. 7  shows a cut-away view of the projectile  300  of the preferred embodiment of the present invention. The projectile comprises an outer casing  302  preferably made of plastic, glass or other frangible material. The casing  302  must be strong enough to withstand the force of being fired from the launcher  200 , but must be fragile enough so that it shatters upon impact with the target  102 . Inside the casing  302  is a gelatinous adhesive compound  304  which holds a GPS receiver  306 , a radio frequency (RF) transponder  308 , a battery  310 , an antenna  312  and an inertia or pressure switch  314 . These electronic components are preferably placed on a single electronic component or chip  313 . The adhesive material  304  is used to attach the chip  313  to a fleeing vehicle or target and can be any material that helps to absorb the shock generated by the firing of the launcher  200  and the impact with the target, yet also has a cure rate that ensures that the electronic chip  313  sticks to the target  102 . The adhesive  304  must also be able to maintain its adhesive properties in a variety of environmental conditions, such as extreme heat, extreme cold, wet weather, etc. Examples of such adhesives are SUPER GLUE® GEL, product number 05111135-08751 and SUPER STRENGTH ADHESIVE, product number 051131-50096, available from the 3M Company. Although specific examples of the adhesive have been given, it should be understood that any adhesive that meets the requirements of the present invention may be used. 
         [0059]    Contained in the adhesive mixture  304  is the electronic chip  313 . In the preferred embodiment, the electronic chip  313  is initially in an “off” position to conserve the power in the battery  310 . It is connected to the pressure or inertia switch  314  which turns the chip “on” due to the force generated by the firing of the launcher  200  or the impact with the target vehicle  102 . Once the chip  313  is turned “on,” the GPS receiver  306  begins to receive signals from terrestrial satellites to determine its location and conveys that information to the RF transponder  308 . The RF transponder then transmits the information to law enforcement at a central command station who track the fleeing vehicle and direct field officers to its location. Alternatively, the RF transponder  308  may transmit the location of the target vehicle directly to the officer who fired the gun  200  or any other authorized personnel. 
         [0060]    In yet another embodiment of the invention shown in  FIG. 9 , the electronic chip  313  in the projectile  350  is constantly powered or “on.” This eliminates the need for the inertia switch  314 ; however, it requires a means for the battery  310  to be charged so that it has enough energy to power the electronic chip  313  after being fired. The projectile  350  of  FIG. 9  is therefore provided with metal contacts  352  along its sides which are connected to the battery  310  by wires  354 . Corresponding metal contacts in the clip of the launcher  200  (not shown) contact the metal contacts  352  of the projectile to charge the battery  310  from an external power source. Alternatively, the projectile  350  may be kept in a separate battery charging device until just prior to use so that it is fully charged when fired from the gun. It should be understood that other means of charging the battery  310  of the projectile  350  are available, and that the embodiment described above is not meant to limit the scope of the invention. 
         [0061]    In an alternative embodiment shown in  FIG. 10 , rather than using a frangible casing and adhesive, the tracking device, sensors and/or disabling system are embedded within a carrier  32 . The carrier  32  is a pliable, highly sticky mass, which has the approximate shape and size of a baseball. When fired from the launcher  200 , the carrier adheres to a target. Alternatively, as shown in  FIG. 11 , the carrier  400  is ball-shaped, but the outer surface  402  has suction cups  410  attached to it. Each suction cup  410  comprises a flexible cup-shaped body member  412  having an inside cup portion  314  and an outside cup portion  316 . Outside cup portion  316  is attached to a neck  318  which in turn is connected to ball outer surface  302  by a base  320 . The tracking device, sensors and/or disabling system are contained within the carrier  300 , and the carrier  300  is launched from launcher  200  as previously described. When the carrier  300  impacts on the surface of a target, it adheres to the target&#39;s surface by one or more of the cup-shaped body members  312 , thereby tagging the target. 
         [0062]    It is envisioned that the invention will be used in two primary situations. The first is when an officer has pulled a suspect over to the side of the road to investigate whether a crime or other violation has occurred. In this situation, the officer aims the launcher  200  by using the laser pointer  213  and manipulating the articulating joint  208 . He then aims the laser pointer  213  at an appropriate flat surface on the target vehicle  102 . Before exiting his car, the officer preferably activates a toggle switch which powers the trigger and clears the barrel of the gun so that it is ready to be fired. If the suspect attempts to flee, the officer may fire the gun with a portable trigger button that he is carrying. In the second situation, the officer is pursuing a suspect in a fleeing vehicle. Here, he fires the gun using the same process as the first, except that instead of firing the gun using the portable trigger, the officer fires the gun by closing in on the fleeing vehicle and pressing a trigger button from inside his vehicle. In both situations, the vehicle is tracked remotely, from a vehicle or a central command center, eliminating the need to chase the vehicle. 
         [0063]    In yet another embodiment of the invention, a handheld gun may be used to launch the tracking projectile. The handheld device may be based on either a pneumatic or shotgun launcher, and allows the operator greater flexibility in aiming and shooting potential targets.  FIGS. 8   a  and  8   b  show a handheld pneumatic gun  600  similar to the mounted launcher  200  shown in  FIG. 2 . The tracking projectiles  300  may be gravity fed into the gun  600  or may be loaded via a spring clip. The gun  600  is aimed by simply pointing the gun at the intended target and is fired by pulling the trigger  602 . The “charge” is preferably provided by a gas canister attached to the gun. 
         [0064]    In place of the pneumatic power gun described above, a shotgun-based gun may be used. This requires the use of a modified shotgun shell projectile  500 , as shown in  FIG. 8   c.  An explosive charge  508  is contained in an end of the shotgun shell  500  to provide the power to propel the shell  500 . The shotgun shell  500  is encased in an outer plastic sabot sheath  502  as it is propelled from the barrel of the gun, and is released by the sabot sheath  502  as it exits the barrel. Although only pneumatic and shotgun launchers have been disclosed, any type of gun able to propel the tracking projectile could be used, and the invention is not intended to be limited to these two embodiments. 
         [0065]    Although certain presently preferred embodiments of the present invention have been specifically described herein, it will be apparent to those skilled in the art to which the invention pertains that variations and modifications of the various embodiments shown and described herein may be made without departing from the spirit and scope of the invention. Accordingly, it is intended that the invention be limited only to the extent required by the appended claims and the applicable rules of law.