Abstract:
A method including detecting a threat incoming to a vehicle, the vehicle having a plurality of countermeasures including a primary armament and an active protection system, communicating the detected threat to a controller, activating, with the controller, a first sensor in response to the detecting, the first sensor tracking the incoming threat and generating tracking data, routing, with the controller, the tracking data to a plurality of fire control processors, each of the plurality of fire control processors being associated with a respective one of the plurality of countermeasures, and the plurality of fire control processors simultaneously computing respective firing solutions using the tracking data, and determining, with the controller, a preferred countermeasure out of the plurality of countermeasures with which to counter the incoming threat.

Description:
BACKGROUND 
       [0001]    Combat vehicles such as tanks and personnel carriers are indispensible tools in times of war. Generally, such combat vehicles are protected from enemy fire by some type of armor. However, as enemy weapon systems have advanced, passive protection systems, such as armor, have become less effective. As a result, active protection systems have been developed that attempt to defeat threats such as anti-tank guided missiles and rocket propelled grenades before they reach the combat vehicle. Specifically, an active protection system may, upon detection of an incoming threat, launch an interceptor missile to destroy the incoming threat. But active protection systems may be costly to implement and maintain, for instance, because interceptor missiles are expensive compared to traditional rounds. Further, a combat vehicle outfitted with an active protection system may be limited in the number of interceptor missiles it may have onboard at any one time. Vehicle protection systems that are cost effective and extend mission lifecycles are needed. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0002]    A better understanding of the present invention will be realized from the detailed description that follows, taken in conjunction with the accompanying drawings, in which: 
           [0003]      FIG. 1  is an illustration of a hit avoidance system deployed on a combat vehicle. 
           [0004]      FIG. 2  is a functional block diagram of an exemplary embodiment of the hit avoidance system of  FIG. 1 . 
           [0005]      FIG. 3  is an illustration depicting the combat vehicle and hit avoidance system of  FIG. 1  countering an incoming projectile with a primary armament of the combat vehicle. 
           [0006]      FIG. 4  is an illustration depicting the combat vehicle and hit avoidance system of  FIG. 1  countering an incoming projectile with an active protection system of the combat vehicle. 
           [0007]      FIG. 5  is a high-level flowchart illustrating a method of countering an incoming threat using the hit avoidance system of  FIG. 1 . 
       
    
    
     DETAILED DESCRIPTION 
       [0008]    The following disclosure provides many different embodiments, or examples, for implementing different features of the invention. Specific examples of components and arrangements are described below to simplify the present disclosure. These are, of course, merely examples and are not intended to be limiting. 
         [0009]      FIG. 1  is an illustration of a hit avoidance system  100  deployed on a combat vehicle  102 . Hit avoidance system  100  detects, tracks, and attempts to detect incoming threats to combat vehicle  102 . Incoming threats may include anti-tank guided missiles (ATGM), rocket-propelled grenades (RPG), kinetic energy projectiles, or other projectiles capable of damaging a combat vehicle. In general, the hit avoidance system  100  protects combat vehicle  102  by utilizing not only an active protection system but also the vehicle&#39;s primary and secondary armaments. In this manner, incoming threats may be defeated by either munitions fired from a turret-based armament or interceptors fired from an active protection system. Not only does system  100  provide an extra layer of protection for combat vehicle  102 , but it does so in a manner that is cost effective and increases the vehicle&#39;s mission life-cycle. Using cost efficient turret rounds to defeat incoming threats saves expensive interceptor missiles and also prolongs the time the vehicle can operate in the field before it must return to base and rearm. The hit avoidance system  100  will be discussed in greater detail in association with  FIG. 2 . In the current embodiment, combat vehicle  102  is a tank, however, in alternative embodiments the combat vehicle may be an armed personnel carrier, amphibious assault vehicle, sea-going gunship, or some other combat vehicle with at least a primary armament, such as a turret gun. Combat vehicle  102  includes primary armament  104 . In the current embodiment, primary armament  104  is a Mk44 Bushmaster II 30 mm chain gun manufactured by Alliant Techsystems of Minneapolis, Minn. Primary armament  104  is loaded with 30 mm or 40 mm airburst rounds that are designed to detonate in midair and disburse shrapnel in a concentrated area. In alternative embodiments, primary armament  104  may be any other weapon that fires airburst-type rounds or other rounds that, upon detonation, disrupt an area larger than the round itself. Combat vehicle  102  further includes a secondary armament  106 . In the current embodiment, secondary armament  106  is a XM153 Common Remotely Operated Weapons Station (CROWS) mounted with a MK47 Grenade Launcher. Secondary armament  106  may also be loaded with airburst rounds or airburst-type rounds. Alternatively, combat vehicle  102  may not include a secondary armament  106  or the secondary armament may be some other type of vehicle-based weapon capable of firing airburst-type rounds. 
         [0010]    Combat vehicle  102  also includes a sensor system or sensor suite  108 . In the current embodiment, sensor suite  108  may include one or more sensors including radar-based sensors, electro-optical/infrared (EO/IR)-based sensors, laser-based sensors, and other sensors capable of detecting and/or tracking incoming threats to combat vehicle  102 . Additionally, combat vehicle  102  includes an active protection system (APS)  110 . If an incoming threat is detected by one or more of the sensors in sensor suite  108 , APS  110  is capable of almost instantaneously deploying a hard kill countermeasure to destroy the threat. In the current embodiment, the APS  110  is a Quick Kill System from Raytheon Company of Waltham, Mass., but, in alternative embodiments, APS  110  may be another type of active protection system. 
         [0011]      FIG. 2  is a functional block diagram of an exemplary embodiment of the hit avoidance system  100  of  FIG. 1 . As previously discussed, the hit avoidance system  100  attempts to defeat incoming threats to combat vehicle  102 . To do so, hit avoidance system  100  incorporates features customarily found on a combat vehicle such as the sensing devices, armaments, and active protection systems. As such, in the current embodiment, hit avoidance system  100  includes sensor suite  108 , primary and secondary armaments  104  and  106 , and active protection system  110 . 
         [0012]    In more detail, hit avoidance system  100  includes a hit avoidance system controller (HASC)  112 . HASC  112  electronically controls the operation of the hit avoidance system  100 . Generally, HASC  112  is a hardware and software solution operable to process input from the sensing devices on combat vehicle  102 , compute a hit avoidance solution, and initiate hit avoidance action based on the solution. In one embodiment, HASC  112  is a custom computer system with at least a processor and an associated memory that is installed in combat vehicle  102 . The memory may store software that is executable by the processor to control the HASC  112 . In alternative embodiments, however, HASC  112  may be a remote computer system that communicates with the hit avoidance system  100  in combat vehicle  102  over a communication network. 
         [0013]    Hit avoidance system  100  includes both soft kill and hard kill countermeasures. Soft kill countermeasures generally are designed to confuse the targeting mechanism of an incoming threat, thereby reducing the chance of a direct hit. Hard kill countermeasures, such as deployed by APS  110 , are designed to physically counteract an incoming threat by destroying it or physically altering its intended path. In the current embodiment, the soft kill capabilities of hit avoidance system  100  are implemented with a laser warning receiver (LWR)  114  and a multifunction countermeasure (MFCM)  116 , both of which are coupled to the HASC  112 . The LWR  114  is operable to detect laser emissions from laser beam rider missile systems impinging on the combat vehicle  102 . The MFCM  116  is operable to deploy soft kill countermeasures in response to the detection of impinging lasers by the LWR  114 . Further, hit avoidance system  100  includes a passive threat warner (PTW)  118  coupled to the HASC  112 . PTW  118  is operable to detect muzzle flash indicative of the launch of an incoming projectile. 
         [0014]    The sensor suite  108  on combat vehicle  102  is incorporated into the hit avoidance system  100 . In the current embodiment, the sensor suite  108  includes an electro-optical/infrared (EO/IR) sensor  120  and a radar  122 . The EO/IR sensor  120  and radar  122  are coupled to HASC  112  via a sensor suite control (SSC) bus  124 . In more detail, EO/IR sensor  120  is a electro-optical and infrared full-motion video camera system that provides long-range surveillance, acquisition, and tracking. Further, in the current embodiment, the radar  122  is an Active Electronically Scanned Array (AESA) radar system. The sensor suite  108  may alternatively include additional or different sensor systems known in the art. 
         [0015]    The hit avoidance system  100  additionally incorporates the active protection system (APS)  110 . The APS  110  includes a fire control processor (FCP)  124  coupled to the HASC  112 . The APS FCP  124  is operable to calculate firing solutions for the APS  110  based on tracking data from sensor suite  108 , including radar  122 . APS  110  further includes an interceptor launcher  126  coupled to the APS FCP  124 . In one embodiment, interceptor launcher  126  is armed with two types of interceptor missiles to defeat incoming projectiles: a smaller type designed to intercept close-in threats such as RPGs and a larger type designed to intercept fast moving anti-tank missiles and tank rounds. The APS FCP  124  provides firing solutions to interceptor launcher  126  and initiates launches of interceptor missiles. In one embodiment, the interceptor launcher  126  is positioned to launch interceptor missiles vertically as to provide 360 degrees of protection. Also, in some embodiments the radar  122  may be considered part of the APS  110  and thus may be coupled directly to the APS FCP  124 . 
         [0016]    The primary armament  104  and the secondary armament  106  of combat vehicle  102  are also integrated into the hit avoidance system  100 . In the current embodiment, rounds fired from primary armament  104  and secondary armament  106  are used as hard kill countermeasures as well as offensive munitions. Primary armament  104  and the secondary armament  106  are coupled to HASC  112  via a turret FCP  128 . Turret FCP  128  is operable to calculate firing solutions for the armaments  104  and  106  and initiate firings. As mentioned above, in the current embodiment, the primary and secondary armaments  104  and  106  are loaded with airburst rounds, which are typically less expensive than the interceptor missiles launched by the APS  110 . Further, a vehicle with both a turret-based primary armament and an active protection system, such as combat vehicle  102 , typically carries more turret rounds than APS interceptor missiles. 
         [0017]    In operation, hit avoidance system  100  protects combat vehicle  102  from incoming threats by utilizing not only the active protection system  110 , but also the combat vehicle&#39;s primary and secondary armaments  104  and  106 . Generally, if soft kill countermeasures fail to deter an incoming projectile, the hit avoidance system  100  will determine which hard kill countermeasure—primary armament  104 , the secondary armament  106 , or APS  110 —is preferred to counter the threat. Rather than automatically initiating the launch of an APS interceptor missile upon detection of a threat, the hit avoidance system  100  analyzes tracking data from sensor suite  108  and applies one or more algorithms to determine which of the countermeasures most suited to defeat the threat. The inclusion of the primary and secondary armaments in the hit avoidance system&#39;s kill chain bolsters the combat vehicle&#39;s defenses by giving it additional countermeasures that are economical but highly accurate. 
         [0018]    In more detail, hit avoidance system  100  will detect an incoming threat with the passive threat warner (PTW) which  118  scans for muzzle flash—an indication that a projectile has launched. If the PTW  118  detects muzzle flash, threat tracking is handed off to hit avoidance system  100 , so hard kill countermeasures may be initialized. 
         [0019]    Once threat tracking is passed to hit avoidance system  100 , the radar  122  begins tracking the incoming projectile. In the current embodiment, as radar  122  tracks the incoming projectile, it calculates attitude, position, and range data and feeds it to the APS FCP  124  in real-time. Likewise, the EO/IR sensor  120  will track the incoming projectile, providing position data to the turret FCP  128  in real-time. In alternative embodiments, EO/IR sensor  120  and radar  122  may each transmit position data to both the APS FCP  124  and turret FCP  128 . In addition to feeding attitude, range, and position data to FCPs  124  and  128 , the radar  122  will transmit the data to the hit avoidance system controller (HASC)  112 . As APS FCP  124  and turret FCP  128  receive tracking data, they simultaneously calculate firing solutions for their respective munitions. While EO/IR sensor  120  and radar  122  are tracking the incoming projectile and FCPs  124  and  128  are calculating respective firing solutions, HASC  112  analyzes the tracking data and applies one or more algorithms to determine which hard kill countermeasure to utilize first. HASC  112  may take into account at least the following factors when making the determination as to which countermeasure to fire first: (1) distance of incoming projectile from combat vehicle  102 , (2) effectiveness of each countermeasure against threat type, (3) effect of residual shrapnel on combat vehicle  102  and surrounding area, (4) number of rounds for each countermeasure available onboard combat vehicle  102 . This list is not exhaustive and the decision algorithm of HASC  112  may take into account additional or different factors.  FIGS. 3 and 4  depict two possible threat defeat scenarios resulting from the HASC&#39;s determination. 
         [0020]      FIG. 3  is an illustration depicting the combat vehicle  102  and hit avoidance system  100  of  FIG. 1  defeating an incoming projectile  130  with primary armament  104 . In the scenario depicted by  FIG. 3 , HASC  112  has determined that a round fired by primary armament  104  is most suited to counter the incoming projectile  130  based on tracking data provided by sensor suite  108 . HASC  112  sends a command via SSC  124  to the turret FCP  128  to initiate the firing of a round with the primary armament  104 . Subsequently, the turret FCP  128  sends a “slew-to-cue” command to the primary armament  104  such that the main turret slews around to a firing position based on the most current firing solution. In the current embodiment, primary armament fires multiple airburst rounds  132 . The airburst rounds  132  travel along trajectory  134  and detonate immediately prior to reaching projectile  130 . The detonations explode the airburst rounds, creating a concentrated cloud of shrapnel in the path of the projectile  130 . Ideally, the airburst shrapnel destroys the projectile  130  but it may alternatively displace it from its intended trajectory by an amount great enough to prevent a direct hit on combat vehicle  102 . In one embodiment, primary armament  104  may be preferred for countering incoming projectiles at long range (e.g. over 500 meters) because (1) the main turret of primary armament  104  must slew around prior to firing and (2) the risk of harm to the combat vehicle  102  or nearby dismounted soldiers from airburst shrapnel is reduced when the threat is engaged at long range. Additionally, the scenario illustrated by  FIG. 3  may be similar to the scenario in which the HASC  112  determines that the secondary armament  106  on combat vehicle  102  is most suitable to counter the incoming projectile  130 . 
         [0021]      FIG. 4  is an illustration depicting the combat vehicle  102  and hit avoidance system  100  of  FIG. 1  countering the incoming projectile  130  with active protection system  110 . In the scenario depicted by  FIG. 4 , HASC  112  has determined that a long range interceptor missile  136  fired by the APS  110  is most suited to counter the incoming projectile  130  based on tracking data calculated by sensor suite  108 . Once that decision has been made, HASC  112  sends a command to the APS FCP  124  to initiating the firing of interceptor missile  136  from interceptor launcher  126 . In the current embodiment, the interceptor launcher  126  launches vertically from the interceptor missile  136  using pressurized gas—a technique known as soft launching. Once the interceptor missile  136  is away from the combat vehicle, thrusters position it such that it points in the direction of the incoming projectile  130 . Once aligned, a rocket motor is ignited and the interceptor missile  136  is accelerated along trajectory  138  towards projectile  130 . In one embodiment, the interceptor missile  136  contains a focused blast warhead that detonates when in close vicinity to the incoming projectile  130 . 
         [0022]      FIG. 5  is a high-level flowchart illustrating a method  140  of countering an incoming threat using the hit avoidance system  100  of  FIG. 1 . Method  140  begins at block  142  where the laser warning receiver (LWR)  114  detects a targeting laser beam impinging on the combat vehicle  102 . Then, at block  144 , the multifunction countermeasure (MFCM)  116  is activated to jam or decoy the targeting system. At block  146 , the passive threat warner (PTW)  118  detects muzzle flash of a projectile launch. Next, method  140  continues to block  148  where the PTW  118  hands off tracking of the incoming projectile to the hit avoidance system controller (HASC)  112 . Then, at block  150 , the HASC  112  activates the radar  122  to track the incoming projectile. Next, method  140  simultaneously branches to blocks  154  and  156 . In block  154 , the radar  122  calculates the attitude, position, and range of the incoming projectile and reports this tracking data to the APS FCP  124 , which begins calculating a firing solution. Alternatively, the radar  122  may also report tracking data to the turret FCP  128 . Meanwhile, in block  156 , HASC  112  begins calculating which countermeasure would be preferred in countering the incoming threat based in part on tracking data from radar  122 . Next, at block  158 , it is determined which countermeasure—primary armament  104 , secondary armament  106 , or APS  110 —would be preferred in countering the incoming threat. If HASC  112  determines that the primary armament  104  is most suited, method  112  proceeds to block  160  where HASC  112  authorizes the turret FCP  128  to fire primary armament  104 . From block  160 , method  140  concludes to block  162  where turret FCP  128  fires the primary armament  104  at the incoming projectile using the most current firing solution. If, instead, HASC  112  determines that the secondary armament  106  is most suited to counter the incoming projectile, method  112  proceeds to block  164  where HASC  112  authorizes the turret FCP  128  to fire secondary armament  106 . From block  164 , method  140  concludes at block  166  where turret FCP  128  fires the secondary armament  106  at the incoming projectile using the most current firing solution. Finally, if HASC  112  determines that the APS  110  is most suited to counter the incoming projectile, method  112  proceeds to block  168  where HASC  112  authorizes the APS FCP  128  to launch an interceptor missile  136 . From block  168 , method  140  concludes at block  170  where APS FCP  128  launches the interceptor missile  136  from interceptor launcher  126  using the current firing solution. 
         [0023]    The foregoing outlines features of selected embodiments so that those skilled in the art may better understand the aspects of the present disclosure. Those skilled in the art should appreciate that they may readily use the present disclosure as a basis for designing or modifying other processes and structures for carrying out the same purposes and/or achieving the same advantages of the embodiments introduced herein. Those skilled in the art should also realize that such equivalent constructions do not depart from the spirit and scope of the present disclosure, and that they may make various changes, substitutions, and alterations herein without departing from the spirit and scope of the present disclosure, as defined by the claims that follow.