Patent Publication Number: US-11662188-B2

Title: Systems and methods for a dart for a conducted electrical weapon

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. application Ser. No. 16/886,374, filed May 28, 2020, which is a continuation of U.S. application Ser. No. 15/678,794, filed Aug. 16, 2017, now U.S. Pat. No. 10,712,136, which claims priority to, and the benefit of, U.S. Provisional Patent Application No. 62/487,437, filed on Apr. 19, 2017, and entitled “Systems and Methods for a Dart for a Conducted Electrical Weapon,” each of which are herein incorporated by reference in their entirety. 
    
    
     FIELD OF INVENTION 
     Embodiments of the present invention relate to a conducted electrical weapon (“CEW)”. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING 
       Embodiments of the present invention will be described with reference to the drawing, wherein like designations denote like elements, and: 
         FIG.  1    is a block diagram of a conducted electrical weapon (“CEW”) with a practice dart according to various aspects of the present disclosure; 
         FIG.  2    is an implementation of a practice dart according to various aspects of the present disclosure; 
         FIG.  3    is an expanded view of the dart of  FIG.  2   ; 
         FIG.  4    is a cross-section of the practice dart of  FIG.  3   ; 
         FIG.  5    is a front view of the overlay of  FIGS.  2 - 4  and  8   ; 
         FIG.  6    is a cross-section of the cap of  FIG.  3   ; 
         FIG.  7    is a diagram of an officer wearing a suit suitable for receiving and holding one or more practice darts; and 
         FIG.  8    is a diagram of two darts adhering to the suit of  FIG.  7   . 
     
    
    
     The numerical designators in the drawing indicate the following:  110 : handle,  112 : processing circuit,  114 : user interface,  116 : launch circuit,  118 : signal generator,  130 : deployment unit,  132 : practice dart,  134 : propellant,  200 : practice dart,  210 : overlay,  220 : cap,  230 : body,  240 : filament,  310 : spear,  312 : barb,  314 : barb,  320 : passage,  330 : length,  410 : length,  412 : barb position,  420 : lip,  430 : wall,  510 : blade,  520 : nose,  530 : length,  532 : width,  534 : width,  536 : end,  538 : material,  540 : edge,  630 : height,  640 : edge,  650 : width,  700 : officer,  720 : shirt,  730 : pants,  810 : overlay,  820 : cap,  830 : body,  840 : filament, and  850 : distance. 
     DETAILED DESCRIPTION OF INVENTION 
     Police officers are issued equipment such as guns and conducted electrical weapons (“CEWs”) in order to perform their duties. Police officers are required to practice with equipment in order to maximize its safe and effective use in a stressful situation. Preferably, training is performed on equipment as similar as possible to the equipment an officer uses in the field. Because a CEW is a less lethal weapon, training may include using a CEW to launch actual darts (e.g., electrodes) toward a human target. 
     A CEW may include a handle and a deployment unit (e.g., cartridge). A deployment unit may be removeably coupled to a handle. A deployment unit may include one or more darts (e.g., electrodes) and a propellant. Upon activation, the propellant propels the one or more darts toward a target. As the darts fly toward the target, a filament deploys between the one or more darts and the CEW so that the darts remain electrically coupled to the CEW. The filament may be stored in the body of a dart, so that movement of the dart toward the target deploys the filament to bridge (e.g., span) the distance between the target and the CEW. 
     The one or more darts impact the target. Upon impact, the one or more darts may mechanically couple to the target. Conventional electrodes (e.g., darts) use a spear for piercing target clothing and/or tissue. Spears typically include one or more barb. The one or more barbs mechanically couple to clothing or target tissue to retain the spear in target clothing and/or tissue. 
     While the darts are proximate to or embedded in target tissue, a signal generator of the CEW may provide a current (e.g., stimulus signal) through the target via the one or more electrodes. The current may impede locomotion of the target by causing pain and/or interfering with use of skeletal muscles of the target. 
     A typical CEW cartridge fires two darts. The spear of the darts may have barbs to retain the dart in target clothing and/or tissue. During training, a human target may wear protective clothing to reduce the effect of the current provided by the CEW and/or to reduce injury by the darts piercing and entering target tissue. 
     Training with a CEW against live targets may be improved, at least from the perspective of the target, by using a practice dart that is similar in weight and flight, but that does not pierce target clothing or tissue or deliver a high voltage current through the target. 
     In one implementation, a practice dart may modify the spear of the dart that pierces target tissue to include a structure for attaching a fired dart to the clothing of a user without piercing target tissue. Further, the conductive filament that stretches between a dart at the target and the signal generator of the handle may be replaced with a non-conductive filament to preclude delivery of a stimulus signal through the target. 
     A CEW suitable for practice on live targets includes handle  110  and deployment unit  130 . Handle  110  includes user interface  114 , processing circuit  112 , launch circuit  116 , and signal generator  118 . Deployment unit  130  includes one or more practice darts  132  and propellant  134 . 
     Handle  110  may include any conventional handle that performs the functions of a handle of a CEW and receives deployment units for launching darts. Practice dart  132  may operate in such a manner as to improve the live-target experience without requiring changes to handle  110 . For example, a user could prepare for a practice session by replacing conventional deployment units that include darts with spears that have barbs with deployment unit  130  that is suitable for practice with no changes to handle  110 . 
     A user interface may include one or more controls that permit a user to interact and/or communicate with a CEW. Via a user interface, a user may control (e.g., influence, select) the operation (e.g., function) of a CEW. A user interface may provide information to a user. A user may receive visual, haptic, and/or audible information via a user interface. A user may receive visual information via devices that visually display (e.g., present, show) information (e.g., LCDs, LEDs, light sources, graphical and/or textual display, display, monitor, touchscreen). A user interface may include a communication circuit for transmitting information to an electronic device (e.g., smart phone, tablet computer, laptop computer) for presentation to a user. 
     In an implementation, user interface  114  may include a trigger for initiating (e.g., starting) the launch of practice dart  132 . Initiation of launch may be accomplished by activating propellant  134 . Propellant  134  may provide a force to practice dart  132  to launch (e.g., move) practice dart  132  toward a target. 
     A processing circuit includes any circuitry and/or electronic subsystem for performing a function. A processing circuit may include circuitry that performs (e.g., executes) a stored program. A processing circuit may include a digital signal processor, a microcontroller, a microprocessor, an application specific integrated circuit, a programmable logic device, logic circuitry, state machines, MEMS devices, signal conditioning circuitry, communication circuitry, a radio, analog-to-digital converters, digital-to-analog converters, data busses, address busses, memory, and/or a combination thereof in any quantity suitable for performing a function and/or executing one or more stored programs. 
     A processing circuit may provide and/or receive electrical signals whether digital and/or analog in form using any conventional protocol. A processing circuit may receive information, manipulate the received information, and provide the manipulated information. A processing circuit may store information and retrieve stored information. A processing circuit may cooperate with a memory to store and/or retrieve information. Information received, stored, and/or manipulated by the processing circuit may be used to perform a function, control a function, and/or to execute a stored program. 
     A processing circuit may detect the operation of a control (e.g., button, switch, touch screen) of a user interface. A processing circuit may perform a function of the device responsive to operation of a control. A processor may perform a function, halt a function, resume a function, or suspend a function of the device of which the control and the processor are a part. A control may provide analog or binary information to a processor. Operation of a control includes operating an electromechanical device or selecting a portion of touch screen. 
     A processing circuit may control the operation and/or function of other circuits and/or components of a system. A processing circuit may receive status information regarding the operation of other components of a system, perform calculations with respect to status information, and provide commands (e.g., instructions) to one or more other components for the component to start operation, continue operation, alter operation, suspend operation, or cease operation. Commands and/or status may be communicated between a processing circuit and other circuits and/or components via any conventional protocol. A CEW handle may include a processing circuit. Each CEW deployment unit may include a processing circuit. A processing circuit of a handle may communicate with a processing circuit of a deployment unit when the deployment unit is in communication with the handle. Generally, a deployment unit may communicate with a handle when the deployment unit is physically coupled to the handle. 
     In an implementation, processing circuit  112  receives instructions from a user via user interface  114 . Responsive to a user instruction (e.g., command), processing circuit  112  may perform one or more functions. Functions may include controlling (e.g., cooperate with) a power supply (not shown), signal generator  118 , and/or launch circuit  116 . Processing circuit  112  may control signal generator  118  in whole or part to provide a stimulus signal. Processing circuit  112  may control launch circuit  116  in whole or part to provide a launch signal to activate propellant  134  to provide a force to practice dart  132  to launch practice dart  132  from deployment unit  130 . 
     A launch circuit provides a signal to a deployment unit to activate the launch of one or more darts (e.g. electrodes) from a deployment unit. The deployment unit contains a propellant (e.g., pyrotechnic, compressed gas). The launch signal produced by the launch circuit activates the propellant. As discussed above, upon activation of the propellant, one or more darts are launched from the deployment unit toward a target. 
     In an implementation, launch circuit  116  cooperates with processing circuit  112  to activate of propellant  134 . Responsive to processing circuit  112 , launch circuit provides an electrical signal to propellant  134 . Responsive to the electrical signal, propellant  134  releases a force that propels practice dart  132 . The force may include a rapidly expanding gas generated by combustion of a pyrotechnic and/or release of a compressed gas. 
     A signal generator provides a signal (e.g., stimulus signal) for interfering with locomotion (e.g., movement) of a human or animal target. A signal may include a current. A signal may include one or more pulses of current. A signal may include a series of (e.g., number, two or more) current pulses. A pulse of current may be provided at a voltage. Pulses may be delivered at a pulse rate (e.g., 22 pps) for a period of time (e.g., 5 seconds). Each pulse of a stimulus signal may have a pulse width. 
     A stimulus signal may be delivered to a target. A signal generator may provide a signal at a voltage of sufficient magnitude to ionize air in one or more gaps in series with the signal generator and the target to establish one or more ionization paths to sustain delivery of the signal through the target. The signal provided by a signal generator may provide a current through target tissue to interfere with (e.g., impede, disable) locomotion of the target. A signal generator may provide a signal at a voltage to impede locomotion of a target by inducing fear, pain, and/or an inability to voluntarily control skeletal muscles. 
     A signal generator may receive electrical energy from a power supply. A power supply may include a battery. A signal generator may convert the energy from one form of energy into a stimulus signal for ionizing gaps of air and/or interfering with locomotion of a target. 
     A CEW may utilize any conventional propellant to launch darts (e.g. electrodes) towards a target. 
     A practice deployment unit, such as deployment unit  130 , performs many of the functions of a non-practice deployment unit before, during and after launch. A practice deployment unit performs many of the same functions of a non-practice deployment unit in the same manner as the non-practice deployment unit. 
     Before launch, a practice deployment unit stows one or more practice darts. The practice deployment unit has a form factor and control interface that is similar to a non-practice deployment unit, so that the practice deployment unit may be inserted into a conventional handle. 
     During launch, a practice deployment unit receives the same signals (e.g., launch signal, stimulus signal) provided to a non-practice deployment unit. The launch signal initiates propellant  134  to launch one or more practice darts, such as practice dart  132 . A practice dart exits the practice deployment unit in the same manner as a non-practice dart. 
     In flight, a practice dart displays similar characteristics of motion to a non-practice dart. The movement of a practice dart toward a target deploys a filament behind the dart that mechanically, and possibly electrically, couples the practice dart to the deployment unit. A practice dart exits the deployment unit at about the same velocity as an electrode from a non-practice deployment unit. A practice dart strikes the target with about the same amount of force as the non-practice dart. However, a practice dart does not pierce the tissue of the target. A practice dart preferably does not deliver the current through the target even while the one or more practice darts are positioned proximate to target tissue. 
     Practice dart  132  performs the functions of a practice dart as discussed above. Dart  200  is an implementation of a practice dart. Dart  200  may include overlay  210 , cap  220 , dart  230 , and filament  240 . Dart  230  may include spear  310 . Spear  310  may include one or more barbs, such as barb  312  and  314 . Barbs  312  and  314  are positioned at various positions along a length of spear  310 . 
     In an implementation, dart  230  may be a conventional electrode (e.g., dart, non-practice dart) that may be used in a conventional (e.g., non-practice) deployment unit. Even filament  240  may be a conventional filament that conducts the stimulus signal. Placing cap  220  over spear  310  reduces the likelihood that spear  310  will pierce the target and enter target tissue. Cap  220 , if formed of a non-conductive material, will reduce the likelihood that the stimulus signal will be delivered to or through the target because cap  220  may interfere with formation of a circuit through the target. 
     In another implementation, dart  230  may be a conventional electrode in all aspects except for filament  240 . A practice dart, as discussed above, may include a non-conductive filament. A non-conductive filament in all darts proximate to the target precludes delivery of the stimulus current to or through the target. Even if filament  240  is non-conductive, filament  240  may be wound and stowed in dart  230  just as a conventional, conductive filament would be wound and stowed in a conventional electrode so that the launch and flight characteristics of practice dart  132 / 200  are similar to the launch and flight characteristics of a conventional electrode. 
     A conventional CEW electrode may include a spear which lodges in target clothing or penetrates (e.g., pierces) target tissue to deliver a stimulus signal. A spear may include one or more barbs which prevents the easy removal of the spear from clothing or tissue. In an implementation of a practice dart, a cap may be placed over the spear and barbs to prevent puncturing target tissue and/or stop delivery of a stimulus signal. 
     To facilitate assembly of a practice dart, a cap may have one or more passages (e.g., tunnel, cavity) into which the spear of the dart may be positioned (e.g., penetrate, inserted into). A passage may have any shape such that the spear is covered when the cap is placed over the spear. Further, an interior surface of the cap may interfere with a portion of the spear (e.g., barb, base) to mechanically couple (e.g. fasten) the cap to the spear and/or the body of the dart. 
     A cap may couple to a dart by a mechanical interference between a barb of the spear and a portion of the cap. The interior of the cap may include one or more protruding lips (e.g., ridge, protrusion, projection, protuberance) positioned along wall  430  which interfere with one or more barbs of the spear to retain the cap around the spear. A lip may be positioned at any position along a circumference of the cavity. A lip may extend around the entire circumference of a cavity. For example, a round passage may have a lip which forms a circular ridge around an interior of the cap. A rectangular-shaped passage may have a lip on one or more sides of the passage. Passage width  650  may be of any width which allows the spear to be inserted into the passage to establish an interference between one or more of the barbs and the interior of the cap. 
     In an implementation, spear  310  has one or more barbs  312  and  314 . Cap  220  has protruding lip  420  with height  630  and an overall cap length  330 . Cap length  330  is sufficiently long such that spear  310  is fully covered (e.g., a tip of spear does not extend beyond cap  220 ) when spear  310  is positioned in passage  320 . Barb  314  of spear  310  is positioned at distance  412  along length  410  of spear  310 . Barb position  412  and lip height  630  are such that interferes with lip  420  interferes with barb  314  to mechanically retain cap  220  over spear  310 . Lip  420  may flex (e.g., move) to permit barbs  312  and  314  to pass by lip  420  when spear  310  is inserted into passage  320 . 
     Spear  310  may be further retained or solely retained (e.g., no lip) in passage  320  by an adhesive. An adhesive injected into (e.g., applied to) passage  320  before or after spear  310  is positioned in passage  320 . An adhesive may mechanically couple spear  310  to an interior of cap  220 . Applying an adhesive to the end portion of cap  220  that is positioned proximate to body  230  may mechanically couple cap  220  to body  230 . 
     An overlay may be wrapped over and/or around a cap. An overlay enables a practice dart to attach (e.g., adhere) to a target without injury to the target. An overlay enables a practice dart to attach securely to a target. An overlay permits a dart to approach (e.g., fly toward) a target at a wide variety of angles and velocities and still securely attach. A target may wear (e.g., be covered with) a material (e.g., suit, particular clothing) that cooperates with the overlay to enable the overlay to securely attach to the target. 
     An overlay may be constructed of any material that couples to the material worn by the target. The material of an overlay may include a first structure and the material worn by the target may include a second structure so that when the overlay comes into contact with the material worn by the target, the first structure mechanically couples to the second structure to mechanically couple the overlay to the target suit. 
     For example, a hook-and-pile (e.g., hook-and-loop) material has two structures, hooks and loops. Hooks may be positioned on a piece of material that is separate from the material that includes the loops. A piece of material with hooks or loops may mechanically couple to a piece of material that has loops or hooks respectively when the materials come into contact. A hoop may mechanically couple to a hook and vice versa to mechanically couple to two previously separate materials together. A target suit may be formed, for example, of loop material and an overlay formed of hook material such that when the dart hits (e.g., impacts) the target suit, the dart adheres to the target suit. 
     An overlay may perform the additional function of reducing a force of impact transferred to a target. An overlay may be formed of a material that compresses on impact to reduce an amount of force transferred by the momentum of the practice dart to the target. An overlay may be formed of layers of different types of material to reduce a force of impact. Each layer may have different characteristics to reduce the transfer of force from a practice dart to a target. A thickness of one or more materials of an overlay may contribute to reducing a force of impact. 
     An exterior of a cap may have any shape. An overlay may cover all or part of the exterior of a cap. An overlay may cover only a portion of a cap that is most likely to strike a target (e.g., tip). An overlay may nearly completely cover a cap so that any portion of the cap that likely may strike a target is covered with the overlay to facilitate coupling the dart to the target. An overlay may further extend beyond a cap to cover all or part of a body of a dart. 
     An overlay may mechanically couple to a cap and/or a body of a dart using any conventional method. 
     Covering all sides of a cap with an overlay, as opposed to just the tip of the cap, facilitates coupling the practice dart to the target when the flight of the dart does not direct the tip of the dart directly toward the target. Generally, a bullet fired from a conventional firearm spins as it flies so that the tip of the bullet strikes the target as opposed to the side or back of the bullet. If the bullet does not spin at sufficiently high revolutions per minute, the bullet may tumble. If the bullet tumbles, at impact with the target, the bullet may be oriented such that the side of the bullet, as opposed to the tip, first strikes the target. 
     It is possible that a practice dart may not spin at a sufficiently high rate to maintain the tip of the practice dart directed toward the target. It is possible that the practice dart may be oriented at an angle, with respect to straight line flight from the CEW to the target, when the practice dart strikes the target. An overlay that covers at least a portion of the sides of a cap and/or body of the dart increases a likelihood that the material of the overlay will couple to the material of the suit worn by the target as discussed below. 
     It is also possible that the flight of a practice dart is oriented at an angle with respect to a target so that the practice dart would strike the target at an angle even if the flight of the practice dart oriented the tip toward the target. Further, due to the force exerted by the trailing filament of a practice dart and/or the relatively low velocity of flight, a practice dart may turn (e.g., change its orientation) on impact so that a side of the dart contacts the target. Regardless of the reason, a practice dart that includes an overlay on one or more of its sides increases the likelihood that the practice dart may couple to the target upon impact. 
     In an implementation, cap  220  has a hexagonal shape. An opening to passage  320  is positioned in a tip (e.g., top, end) of cap  220 . The six sides of the hexagonal shape are positioned along length  330  of cap  220 . Overlay  210  includes six blades  510 . Each blade is suitable for covering one side of cap  220 . Each blade has width  534 . Width  534  roughly corresponds to the width of each side of cap  220 . Each blade  510  flexibly couples to nose  520 . The width of the material that couples each blade  510  to nose  520  is width  532 . While overlay  210  is positioned to cover cap  220 , nose  520  covers the tip of cap  220 . Nose  520  may couple to tip of cap  220 . Edge  540  of nose  520  may cover substantially all of the tip of cap  220 . 
     Each blade  510  folds over cap  220  to be positioned on a respective side of cap  220 . Each blade  510  may couple to a respective side of cap  220 . The material  538  between each blade  510  and edge  540  of nose  520  may be reduced to width  532  to facilitate folding each blade  510  from nose  520  to the respective side of cap  220 . 
     A length of each blade  510  may be length  530 . In an implementation, length  530  may be approximately equal to length  330  of cap  220 . In another implementation, length  530  may be greater than length  330  so that each blade  510  extends beyond cap  220  to body  230  of practice dart  200 . 
     The shape and size of practice dart  200  with cap  220  and overlay  210  may be suitable to insert into the body of a non-practice deployment unit so that practice dart  200  may be launched from a conventional deployment unit having been launched using the conventional propellant as discussed above. 
     An overlay and a target suit may be formed using any conventional hook-and-loop material. A target suit may be formed entirely of the hook or loop portion of hook-and-loop material or hook or loop portion of hook-and-loop material may be positioned at particular locations on the target suit. An overlay, as discussed above, may include the loop or hook portion of hook-and-loop material and cover all or part of the cap and/or body. 
     In an implementation of a target suit, officer  700  wears shirt  720  and pants  730  made of a material suitable for coupling to overlay  210  of practice dart  200 . In an implementation, shirt  720  and pants  730  are at least partially formed of hook-and-loop material that includes loops while overlay  210  of practice dart  200  is formed of hook-and-loop material that includes hooks. Officer  700  may further wear protective headgear also made of hook-and-loop material that includes loops. 
     Shirt  720  and pants  730  permit officer  700  to move (e.g., walk, run, jump, climb) so that during a practice session, officer  700  may play the part of a live target. During a practice session, CEW users may launch one or more darts toward officer  700 . Officer  700  may be hit with one or more darts. One or more of the darts that strike officer may couple to shirt  720  and/or pants  730  worn by officer  700 . Once a dart couples to shirt  720  or pants  730 , the stimulus signal provided by the CEW may be blocked either by non-conductive cap  220  or by the fact that filaments  240  are non-conductive. 
     When one or more darts adhere to officer  700 , the distance between darts is distance  850 . The CEW user may detect distance  850  to determine whether distance  850  would be sufficient so that the stimulus signal would be likely to cause muscle lockup. If the distance is not suitable, the CEW user may launch additional darts to practice getting a suitable distance  850 . 
     While the preferred embodiment of the invention has been illustrated and described, it will be appreciated that various changes can be made therein without departing from the spirit and scope of the invention. Examples listed in parentheses may be used in the alternative or in any practical combination. As used in the specification and claims, the words ‘comprising’, ‘comprises’, ‘including’, ‘includes’, ‘having’, and ‘has’ introduce an open-ended statement of component structures and/or functions. In the specification and claims, the words ‘a’ and ‘an’ are used as indefinite articles meaning ‘one or more’. When a descriptive phrase includes a series of nouns and/or adjectives, each successive word is intended to modify the entire combination of words preceding it. For example, a black dog house is intended to mean a house for a black dog. In the claims, the term “provided” is used to definitively identify an object that not a claimed element of the invention but an object that performs the function of a workpiece that cooperates with the claimed invention. 
     The location indicators “herein”, “hereunder”, “above”, “below”, or other words that refer to a location, whether specific or general, shall be construed to refer to any location in the specification.