Abstract:
Described are systems and methods for actively countering certain forces experienced by, for example, a person within a vehicle. Adverse effects of blast waves of a mine or other explosive device (including improvised explosive devices [IEDs]) may be mitigated by the countermeasures systems, which may include any or all of a first responder unit (FRU), a control display assembly (CDA), processors, sensors, and an electronic safe and arm device (ESAD). Each component assembly may be incorporated into a line replaceable unit (LRU) if desired, although such incorporation is not necessary.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims the benefit of (1) U.S. Provisional Patent Application Ser. No. 61/689,468, filed Jun. 6, 2012, and entitled “Physical Design Criteria for Active Blast Countermeasure System” and (2) U.S. Provisional Patent Application Ser. No. 61/689,471, filed Jun. 6, 2012, and entitled “Active Blast Countermeasure System,” the entire contents of both of which applications are incorporated herein by this reference. 
     
    
     FIELD OF THE INVENTION 
       [0002]    This invention relates to systems and methods for actively countering forces experienced by an object or person and more particularly, although not exclusively, to systems and methods for actively countering forces experienced by a manned (or unmanned) vehicle upon encountering blast waves of a mine or other explosive device or other undesired forces. 
       BACKGROUND OF THE INVENTION 
       [0003]    U.S. Patent Application Publication No. 2012/0239247 of Eridon, whose contents also are incorporated herein by this reference, purports to disclose “systems and methods for mitigating the effects of sudden accelerative forces on vehicles due to, for example, land mines and improvised explosive devices (IEDs).” See Eridon Application, p. 1, ¶0002. Described generally in the Eridon Application is such a system having sensors, a control system, countermeasures, and a human interface. According to the Eridon Application, the control system,
       which is communicatively coupled to the plurality of sensors and countermeasures, is configured to determine the dynamic response of [a] vehicle based on the set of acceleration signals, then determine whether mitigation is required based on the dynamic response of the vehicle—e.g. whether the dynamic response of the vehicle is likely to cause harm to occupants of the vehicle. If it is determined that mitigation is required, [the] control system produces one or more countermeasure signals selected to at least partially counteract the dynamic response . . . . Countermeasures then activate in response to the one or more countermeasure signals, thereby at least partially counteracting the dynamic response of [the] vehicle.
 
See id., pp. 1-2, ¶0017 (numerals omitted).
       
 
         [0005]    Absent from the skeletal Eridon Application is, among other things, any discussion of numerous components of a satisfactory countermeasures system. No comprehensive trigger and activation system (TAS) is described, for example, and the sole identifications of a “human interface” in the Eridon Application are a block in the diagram of its  FIG. 1  and the statement that it may include “any combination of processors, memory, storage, displays, [and] input devices.” See id., p. 3, ¶0029. Further, the only sensor detail provided in the Eridon Application relates to a particular piezoresistive accelerometer sold by a company called Measurement Specialties, and the countermeasures identification is limited to, generically, “an explosive or a propellant” possibly provided by DuPont. See id., ¶¶0027-28. 
       SUMMARY OF THE INVENTION 
       [0006]    The present invention seeks to supply multiple novel components and techniques for creating active countermeasures systems deployable under a wide variety of hostile and other conditions. An exemplary TAS may, for example, comprise any or all of a first responder unit (FRU), a control display assembly (CDA), processors, sensors, and an electronic safe and arm device (ESAD). Each component assembly may be incorporated into a line replaceable unit (LRU) if desired, although such incorporation is not necessary. 
         [0007]    Together with appropriate countermeasures, the TAS may be used to protect crew members of a vehicle from injury or death caused by, for example, IED or mine blasts or vehicle collisions or rollovers. Systems of the invention additionally may record event or damage information (for maintenance, evaluation, or otherwise) or transmit it remotely to alert other vehicles or headquarters operations of impending danger. The Global Positioning System (GPS) or any other suitable locator system may be used in connection with the invention. 
         [0008]    The FRU is configured to allow personnel outside a vehicle to disable the countermeasures of the vehicle when appropriate to do so. Should personnel within the vehicle be injured or trapped, for example, first responders may need to breach the vehicle hull or otherwise attempt to enter the vehicle for rescue purposes. Because in some cases these actions could risk activation of any undeployed countermeasures, to avoid further risk to life and property first responders desirably may disable the countermeasures before acting. Preferably (although not necessarily) at least one FRU is mounted near the front or rear of the vehicle so as to be accessed externally thereof; a locking cover or other structure may be provided to reduce the possibility of inadvertent or improper disabling of the countermeasures. 
         [0009]    The CDA is intended to allow crew of a vehicle to monitor and control status of the countermeasures systems. It preferably provides visual indication of system status, although aural, tactile, or other status indications may be provided alternatively or additionally. Equally preferably, the CDA comprises multiple switches necessarily operated in certain sequences and at certain time intervals to reduce risk of unintended arming or disarming of the countermeasures by the vehicle crew. The switches, further, beneficially may have differing actuating mechanisms, although such differing mechanisms are not required. 
         [0010]    One or more processors may be utilized as part of each countermeasures system of the present invention. Preferably the processors are dual-core, allowing for parallel processing to occur. Data buses may transfer signals to and from the processors, which also may communicate electrically with a system interface chip (integrated circuit). Processors may control, provide information to, or receive information from, any or all of the FRU, CDA, and ESAD, vehicle sensors, and vehicle safety equipment such as airbags, active seat controls, intelligent clothing, seatbelt pretensioners, etc. 
         [0011]    Sensors associated with the present invention may sense any or all of pressure, angular movement rate, acceleration, strain (deformation), force, displacement, velocity, or electric or magnetic field strength. Because the sensors may be deployed in electrically-noisy environments, signals from the sensors may be encoded using, for example, Manchester coding principles. Preferably, multiple sensors are used on each vehicle, with at least some not co-located with others. If desired, countermeasures deployment may be conditioned on certain signal types and durations being received from multiple non-co-located sensors. 
         [0012]    The ESAD functions to arm and initiate countermeasures upon command of a processor. Like various other aspects of the inventive systems, the ESAD preferably “fails safe”—i.e. if it is non-functional, it enters or reverts to a mode in which countermeasures cannot activate. Fuze cord or any other suitable material may connect the ESAD to the countermeasures. 
         [0013]    Countermeasures themselves may be of varying types yet remain consistent with the present invention. Advantageously, however, countermeasures may include cartridges into which ejectable masses and charges are loaded. Currently preferred ejectable masses are predominantly solids (as opposed to liquids or gases), with preferred solids either being disintegrable or comprising multiplicities of disintegrated particles. If so, the likelihood of serious injury to a bystander impacted by a portion of the ejected mass may be reduced. 
         [0014]    Cartridge countermeasures may be placed in barrels mounted to or otherwise connected or attached to vehicles. The barrels may be constructed in sets or individually as desired and configured to receive cartridges in any manner allowing initiation of the propellant. In some versions of the invention, banks of barrels are mounted at the four corners of the roof of a vehicle. Alternatively or additionally, barrels may be mounted on vehicle sides, fronts, or rears. Presently preferred in some versions is that barrels not be placed on the vehicle undercarriage, although such placement could occur in other versions. Because the cartridges are separate from the barrels, the cartridges may be transported apart from the barrels and loaded only when needed, further reducing risk of undesired countermeasure deployment. 
         [0015]    It thus is an optional, non-exclusive object of the present invention to provide systems and methods for countering at least certain undesired forces acting on a vehicle. 
         [0016]    It is another optional, non-exclusive object of the present invention to provide systems and methods for devising countermeasures systems deployable under a wide variety of conditions. 
         [0017]    It is also an optional, non-exclusive object of the present invention to provide systems and methods incorporating some or all of an FRU, a CDA, processors, sensors, and an ESAD, any of which may be incorporated into an LRU. 
         [0018]    Numerous other objects, feature, and advantages of the present invention will be apparent to those skilled in relevant fields with reference to the remaining text and the drawings of this application. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0019]      FIG. 1  is a block diagram of aspects of a TAS consistent with the present invention. 
           [0020]      FIG. 2  is a front elevational view of an exemplary CDA consistent with the present invention. 
           [0021]      FIG. 3  is a partially-schematicized, cross-sectional view of portions of a countermeasure consistent with the present invention. 
           [0022]      FIG. 4  is a partially-schematicized view of fuze or detonation cord connecting a countermeasure of the type shown in  FIG. 3  to an ESAD consistent with the present invention. 
           [0023]      FIGS. 5A-F  are various views of possible configurations of countermeasures of the type shown in  FIG. 3 . 
           [0024]      FIG. 6  illustrates an exemplary algorithm for deploying one or more countermeasures of the type shown in  FIG. 3 . 
           [0025]      FIG. 7  is a perspective view of a vehicle including countermeasures of the type shown in  FIG. 3 . 
       
    
    
     DETAILED DESCRIPTION 
       [0026]    Depicted in  FIG. 1  is a block diagram of an exemplary TAS  10  of the present invention. TAS  10  may include FRU  14 , CDA  18 , processor  22 , one or more sensors  26 , ESAD  30 , and one or more countermeasures  34 . Although conceivably useful wherever force-related countermeasures are desirably deployed—as to prevent vehicle rollover, for example, TAS  10  is especially designed for use in connection with a vehicle (labeled “V” in  FIG. 7 ) operating in a theatre in which IEDs, mines, or other explosive devices may be present. 
         [0027]    As illustrated in  FIG. 1 , FRU  14  includes at least switch  38 . Switch  38  preferably is interposed in the main power supply line  42  of the vehicle between power supply  46  (e.g. a battery or electrical generator) and ESAD  30  to which countermeasures  34  are connected. If switch  38  is open, electricity is not available for ESAD  30  to arm the countermeasures  34  for deployment. 
         [0028]    FRU  14  beneficially may include a box housing switch  38  and be either attached to or integrated into a hull of a vehicle so as to be accessible externally thereof. Alternatively, FRU  14  may comprise a cover for switch  38  or any other object or assembly configured to restrict access to the switch  38 . In at least some embodiments of the invention, FRU  14  will be locked, limiting access to switch  38  to those possessing an appropriate unlocking key or tool or knowing a suitable combination of symbols. 
         [0029]    In particular, first responders to an accident or catastrophe involving the vehicle may need to breach its hull or otherwise enter its interior so as to rescue personnel or equipment contained therein. Entry activities of these first responders, or other actions impacting the vehicle, could risk activation of as-yet undeployed countermeasures  34 . Accordingly, the first responders may desire to access and open switch  38  upon arrival at the vehicle so as to reduce the possibility of countermeasures  34  deployed undesirably. Of course, persons skilled in appropriate fields of endeavor will recognize that FRU  14  is optional and in certain circumstances either may be omitted from TAS  10  or configured otherwise as described herein. 
         [0030]    CDA  18  appears in  FIGS. 1-2 . As noted in  FIG. 1 , CDA  18  beneficially may—but need not necessarily—include (a) at least two safety arming features, (b) at least two manual actions, and (c) an indicator of whether countermeasures  34  are armed. CDA  18  additionally advantageously may be powered by power supply  46  (albeit perhaps after the power undergoes conditioning by power conditioner  50 ), although other sources of electricity possibly may be used instead. Outputs of CDA  18  may be connected electrically to (at least) processor  22 . Although wired connections among various components of TAS  10  typically are preferred, wireless communication among some or all of the components alternatively may occur. 
         [0031]    CDA  18  functions to, among other things, allow crew of a vehicle to control and monitor status of TAS  10 . CDA  18  preferably is positioned in a dashboard of a vehicle with its face  54  visible to the crew and may, for example, include power switch  58  and an associated visual indicator  62 . Also depicted in  FIG. 2  are arm power switch  66  and its associated visual indicator  70 , arm enable switch  74  and its associated visual indicator  78 , and plural bit status indicators  82 . Arm enable switch  74  may be covered by a pivotable or otherwise movable (or removable) cover  86  that must be moved physically in order to access the arm enable switch  74 . 
         [0032]    In at least some versions of the invention, and assuming switch  38  is closed, TAS  10  may be initialized by closing power switch  58  (shown in  FIG. 2  as a two-position toggle switch). In normal operating circumstances, closing power switch  58  illuminates associated indicator  62 , indicating to a crewmember that power switch  58  is closed so as to supply power to CDA  18 . Closing power switch  58  also causes processor  22  to initiate a power-on self-test (POST), with arm power switch  58  and arm enable switch  74  preferably remaining inactive at least until the POST is complete. 
         [0033]    During the POST, bit status indicators  82  preferably flash in an orange hue. Successful completion of the POST causes bit status indicators  82  to remain illuminated for a brief period (e.g. one second) and then darken if all LRUs are deemed to be operating normally. By contrast, if an LRU fails the POST, its corresponding bit status indicator  82  will remain illuminated. Further, if any failure constitutes a safety-critical system fault, TAS  10  will enter a “fail safe” mode, and any attempt to recover from such a mode will, at minimum, require power switch  58  to be toggled off and then back on. 
         [0034]    Following successful completion of the POST, respective arm power and arm enable switches  58  and  74  may become active. Arm power switch  58  preferably is a momentary switch; to initiate arming of countermeasures  34 , an operator toggles the switch  58  and releases it. Under normal operation and proper sequencing, indicator  70  illuminates in a yellow hue. 
         [0035]    One proper sequencing technique requires crew manipulation of arm enable switch  74  to occur within a defined time period following toggling and release of arm power switch  58 . Such a defined time period may, for example, be between approximately 0.5-6.0 seconds. If switch  74  is not manipulated within the period, indicator  70  will de-illuminate and arm power switch  58  will deactivate, necessitating re-toggling and release of switch  58  to re-start the sequence. By contrast, if cover  86  is moved and switch  74  is manipulated within the period, indicator  78  illuminates and TAS  10  enters an “arm enable” mode. 
         [0036]    With TAS  10  in this “arm enable” mode, processor  22  controls deployment of countermeasures  34  (unless switch  38  or  58  is opened). Processor  22  directly or indirectly receives signals from sensors  26  and determines if deployment of any countermeasure  34  is appropriate. If deployment is appropriate, processor  22  signals ESAD  30 . In some versions of the invention, processor  22  may be housed in an enclosure having deformable brackets so as to allow dampening of shocks otherwise likely experienced by the processor  22 . 
         [0037]      FIGS. 3-4  and  5 A illustrate a sample countermeasure  34 . Countermeasure  34  may be assembled as a cartridge to facilitate shipping and storage, for example. It may include housing  90  containing at least mass  94  and charge  98 . Countermeasure  34  may connect to ESAD  30  and initiator  102  using conventional detonation cord  106 . 
         [0038]    Presently-preferred masses  94  are predominantly solids (rather than liquids or gases). Such preferred solids either are disintegrable upon ejection from the vehicle or comprise multiplicities of disintegrated particles. Disintegration of mass  94  upon deployment of countermeasures  34  is preferred so as to reduce likelihood of serious injury to at least some bystanders possibly impacted by mass  94 . 
         [0039]    Charge  98  may be or include any propellant or other substance capable of causing a countermeasure  34  to eject from a vehicle. Upon receipt of a suitable signal from processor  22 , ESAD  30  activates initiator  102 , which in turn ignites detonation cord  106  connected to a countermeasure  34 . Detonation of cord  106  causes deflagration (if pyrotechnic) or other activation of charge  98  so as to eject mass  94  from the vehicle. A single initiator  102  may be employed to launch any number of countermeasures  34 ; alternatively, each countermeasure  34  may be associated with a separate initiator  102 . To expedite initiation, capacitors associated with initiator  102  may be pre-charged under certain conditions. 
         [0040]      FIGS. 5B-F  depict various examples of banks  110  of barrels  114  into which countermeasure  34  may be loaded. Banks  110  may be mounted to vehicles at any suitable time either before or after the vehicles enter a hostile environment. Although cartridges of countermeasures  34  likewise may be loaded into barrels  114  at any time, preferably they remain unloaded until a vehicle is slated to approach or enter an environment in which deployment of countermeasures  34  may be considered reasonably likely. Barrels  114  may be made of metal, composites, or other suitable material and may be attached to or formed within banks  110 . 
         [0041]      FIG. 5B  schematically illustrates a bank  110  containing five barrels  114 , one of which is loaded with a countermeasure  34 . Bank  110  may be mounted onto a vehicle (see, e.g.,  FIG. 7 ) in any desired location. In some embodiments of the invention, a bank  110  is mounted onto a vehicle at or adjacent each of its four corners (front left, front right, rear left, rear right). 
         [0042]    Depending on the locations and types of forces encountered by sensors  26 , any one or more banks  110  may launch countermeasures  34 . Moreover, if a bank  110  includes more than one barrel  114 , less than all countermeasures  34  loaded in the barrels  114  may be launched at any particular time. Launching of countermeasures  34  further may be staggered or sequenced in time (either within a particular bank  110  or between particular banks  110 ). 
         [0043]    Presently preferred is that barrels  114  be vertical (or substantially so) with their openings  118  positioned upward when mounted to a vehicle. In this manner, a countermeasure  34  will be ejected upward from the vehicle upon deployment, producing a downward force vector upon ejection. Such downward force vector is intended to counteract (in whole or in part) an upward force impacting a vehicle because of, e.g., explosion of a mine or IED, collision of the vehicle with an object, or departure of the vehicle from a roadway or other normal travel surface. 
         [0044]    Alternatively, one or more barrels  114  could be tilted or otherwise repositionable relative to a (nominal) vertical orientation. If so, deployment of materials loaded therein could be used to establish different force vectors acting on a vehicle, or the barrels  114  (regardless of orientation) could be used to deploy flares, missiles, projectiles, or other objects for various purposes. Because banks  110  themselves may have substantial mass, they may function as armor for a vehicle. Reactive armor plates or tiles may be deployed, as may any mass associated with a vehicle (e.g. engine, engine cover, battery, water supply, passive armor, etc.). 
         [0045]    TAS  10  may be modular, scalable, and configured to be adapted for use with a variety of vehicles or other objects. Sensors  26  may sense such things as changes in acceleration, pressure, strain (deformation), force, displacement, infrared (IR) signals, radio frequency (RF) signals, acoustic signals, electric or magnetic field strength, or RADAR or LIDAR signals. Those skilled in the art will recognize that other signals, events, or changes may be sensed alternatively or additionally. However, presently preferred as sensors  26  are accelerometers augmented by either or both of strain and force sensors. At least some sensors  26  preferably are housed in enclosures mounted to or integrated into areas of a vehicle such as its A/B/C/D pillars or drivetrain tunnel or in other stiff (rigid) structural locations. 
         [0046]    Data from sensors  26  may be filtered or encoded (or both) to reduce noise or other incorrect information being received by processor  22 . Some versions of TAS  10  further contemplate comparing information from at least two non-co-located sensors  26  as part of an assessment of the validity and location of a blast or other event.  FIG. 6  identifies an example of certain logical conditions in which firing countermeasures  34  may be deemed appropriate. Computational logic assesses information from sensors  22  relating to “Effective G” (as discussed in S. Arepally, et al., “Application of Mathematical Modeling in Potentially Survivable Blast Threats in Military Vehicles,” 26th Army Science Conference, Dec. 1-4, 2008, the contents of which are incorporated herein in their entirety by this reference) and changes in vehicle velocity (dV) as a function of time length (L). In the exemplary case of  FIG. 6  (as simplified for ease of explanation):
       If G is less than a threshold value X or all countermeasures  34  have already fired, TAS  10  remains in a “safe” or “idle” mode.   If G is greater than or equal to X and at least one countermeasure  34  remains unfired, TAS  10  is armed; however, if G subsequently becomes less than X, dV is less than a threshold Y 1  and L is less than a threshold Z, TAS  10  returns to the safe or idle mode.   Once armed, TAS  10  remains so if G is greater than or equal to X or if dV is greater than Y 1  or L is greater than Z.   If dV of one sensor set (S 1 ) exceeds Y 2  (where Y 2 &gt;Y 1 ), dV of a different sensor set (S 2 ) exceeds Y 1 , and L exceeds Z, any unfired countermeasures  34  associated with set S 1  fire.   By contrast, if no dV measurement exceeds Y 2  or L is less than Z, then TAS  10  remains armed but does not fire.       
 
         [0052]    The foregoing is provided for purposes of illustrating, explaining, and describing embodiments of the present invention. Modifications and adaptations to these embodiments will be apparent to those skilled in the art and may be made without departing from the scope or spirit of the invention.