Abstract:
An interceptor system and method for dispensing of multiple kill vehicles, including, a carrier vehicle having a central carrier vehicle axis and axial propulsion integrated into the carrier vehicle, a payload adapter associated with the carrier vehicle for connecting a payload to a boost vehicle, the payload adapter being located aft of the carrier vehicle, and multiple kill vehicles mounted to the carrier vehicle radially around a circumference of the carrier vehicle.

Description:
GOVERNMENT LICENSE RIGHTS 
     This invention was made with Government support under Contract Number W9113M-04-D-0001, awarded by the Missile Defense Agency. The Government has certain rights in this invention. 
    
    
     BACKGROUND 
     1. Field 
     An interceptor system and method are disclosed, such as a system which can be used for mid-course/spaceborne missile defense, and a method which can control such system. 
     2. Background Information 
     Missile defense systems are known which include space-based mid-course, hit-to-kill weapons using a single kill vehicle capability. As referenced herein, a kill vehicle is an spaceborne weapon device which can be dispensed in multiple quantities for engaging a threat after having been transported into a vicinity of the threat by a booster propulsion. Known systems include one or more separate and distinct booster stages, with a single payload attached with multiple kill vehicles. The payload is delivered to a destination (e.g., threat intercept location) using ground control and a separate booster stack. 
     Known ground-based missile defense systems have been developed for short, medium and long-range missile defense. A class of interceptors known as mid-course, kinetic interceptors provide payloads with aggressive flight profiles to counter current and future threats An integrated axial payload was developed for application in all phases of mid-course flight (early/mid/late) and across these weapon interceptors (kinetic energy interceptor (KEI)/Aegis Ballistic Missile Defense (ABMD). 
     The payload possesses propulsion resources in both “delta-V” and axial acceleration. The delta-V represents a maximum change that the propulsion system can impart on a velocity for increased range of the payload to engage a threat, while the axial acceleration can aid in cross-range/reach (lateral movement) for the payload. 
     Targeting of a threat is performed with a combination of ground radars and on-board payload infrared (IR) sensors. Because known systems are directed to use of a single kill vehicle, any space-based communication capability is destroyed during engagement with a threat. That is, communication is only maintained up to the point in time where the payload is expected to encounter a threat, where the kill vehicles physically hit-to-kill the threat objects. 
     SUMMARY 
     An interceptor system is disclosed herein for dispensing of multiple kill vehicles, comprising: a carrier vehicle having a central carrier vehicle axis and axial propulsion integrated into the carrier vehicle; a payload adapter associated with the carrier vehicle for connecting a payload to a boost vehicle, the payload adapter being located aft of the carrier vehicle; and multiple kill vehicles mounted to the carrier vehicle radially around a circumference of the carrier vehicle. 
     A method is also disclosed for controlling a payload for dispensing of multiple kill vehicles, the method comprising: controlling propulsion of a carrier vehicle, wherein multiple kill vehicles are attached to the carrier vehicle; and managing engagement of the kill vehicles with a threat using on-board guidance of the carrier vehicle, on-board kill vehicle guidance and allocating propulsion resources among extending range of the carrier vehicle, and guiding the carrier vehicle to provide for kill vehicle intercept of a threat based on a controlled dispensing of the kill vehicles. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Other features and advantages disclosed herein will become readily apparent from the detailed description of exemplary embodiments when read in conjunction with the accompanying drawings, wherein like reference numerals have been used to represent like elements, and wherein: 
         FIG. 1  shows an exemplary interceptor system having two booster stages and an integrated payload containing a carrier vehicle, a payload adapter, and multiple kill vehicles; 
         FIG. 2  shows an exemplary integrated payload which can be included in the  FIG. 1  interceptor system; 
         FIG. 3  shows another exemplary embodiment of the integrated payload of the  FIG. 1  system; 
         FIG. 4  shows another exemplary embodiment of the integrated payload of the exemplary  FIG. 1  embodiment; 
         FIGS. 5A-5C  show an exploded view of at least a portion of the exemplary integrated payload of the  FIG. 1  system; 
         FIG. 6  shows an exemplary integrated payload encased in a shroud of the multistage interceptor system of  FIG. 1 ; 
         FIG. 7  shows a perspective view of the exemplary  FIG. 2  integrated payload when viewed from a nose portion of the  FIG. 1  interceptor system; and 
         FIG. 8  shows an exemplary functional block diagram of an engagement controller of the exemplary  FIG. 1  integrated payload. 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  shows an exemplary interceptor system  100  for space dispensing of multiple kill vehicles as a separating payload (e.g., exoatmospheric payload). The integrated payload can be configured to control the payload flight as well as control the multiple booster stages of a booster stack. The  FIG. 1  system includes at least one booster (i.e., booster stage), represented as booster stages  102  and  104  attached to an axially integrated payload  106 . 
     The  FIG. 1  interceptor system  100  is shown to include the booster stages and the integrated payload within a missile shroud  108 . The missile shroud can be included to provide desired missile profile aerodynamic properties, and thermal protection for the payload. 
       FIG. 2  shows an exemplary embodiment of the integrated payload  106 , with the shroud  108  removed. The integrated payload  106  includes a carrier vehicle  202  and a propulsion, represented as propulsion stage  206 , located along the axis. A payload adapter  208  is associated with the carrier vehicle and located between the carrier vehicle and a booster. Plural kill vehicles  210  are mounted to the carrier about the axis  204  via the payload adapter which can also provide, for example, shock/vibration management (e.g., via a damping system such as springs, flexible mounts and/or controlled shock absorption systems). 
     As can be seen in the exemplary  FIG. 2  integrated payload  106 , a propulsion stage  206  is integrated with the plural kill vehicles of the carrier vehicle. Such a configuration can offer improved performance, including an ability to intercept multiple threats at different locations in a field of regard of the interceptor system. Such an integrated structure can be configured in a space and weight efficient manner to enhance fuel management and improve maneuverability. For example, after being maneuvered to within a zone of interest where imminent threats are anticipated, lateral acceleration of the integrated payload can be used to dispense kill vehicles in a strategic, sequential fashion over the entire field of regard, thereby eliminating multiple threats with a single interceptor system. To this end, the booster stages  102  and  104  (or any other booster stages included) can be jettisoned or destroyed when their fuel has been fully dispensed to further improve fuel economy and maneuverability. 
     In exemplary embodiments, the integrated payload  106  can have an overall weight less that of a third booster stage when combined with a single kill vehicle payload. Despite this reduction in weight, improved maneuverability, enhanced range and enhanced functionality can be achieved as will be described herein. 
     The  FIG. 2  embodiment shows the integrated payload includes a carrier vehicle  202 , a propulsion stage  206 , a payload adapter  208  and multiple kill vehicles  210 . The integrated payload can further include an engagement management controller, represented as an avionics and sensor controller  212  for managing engagement of the plural kill vehicles with a threat in the field of regard. A sensor represented as a carrier vehicle sensor  214 A, and a multiple kill vehicle sensor  214 B can be provided for detecting a threat and for interfacing with the engagement management controller  212 . Thus, the engagement management controller can be considered an on-board mission computer for managing the multiple kill vehicles&#39; guidance, control communication and health/status. 
     The engagement management controller can be used to oversee kill vehicle bussing for the multiple dispense events. Such a capability allows engagement of advanced, threats. The engagement management controller can allocate propulsion resources to carrier vehicle propulsion operations (e.g., increase burnout velocity) when needed to more rapidly advance the integrated payload and/or to increase the field of regard that the interceptor system has been missioned to defend. Rather than simply be advanced to a designated location using one or more booster stages, the engagement management controller can intelligently allocate fuel resources to navigate along a trajectory that can be modified in real-time to better adapt to a complex threat or array of threats. Such capability is achieved with the use of on-board propulsion control and threat sensing, coupled with lateral propulsion capability. 
     The integrated axial payload can fit (as exemplary variations) to the ground based interceptor (GBI), the kinetic energy interceptor (KEI) and the standard missile (SM-3) component of the Aegis and Ballistic Missile Defense System. 
     The engagement management controller  212  can execute any of multiple methods, algorithms and software for effectively utilizing the hardware design and architecture of the integrated payload  106 . For example, the engagement management controller, can include: (1) a software and/or hardware module for allocating a propulsion resources of the integrated payload among a booster function for extending range of the integrated payload, and a payload mission for guiding the integrated payload to intercept multiple threats; (2) another (or the same) software and/or hardware module for controlling propulsion resources of the integrated payload for guiding the integrated payload to intercept multiple threats; (3) another (or the same) software and/or hardware module for commanding a dispensing of the plural kill vehicles, and for controlling guidance of the kill vehicles which have been dispensed; and/or (4) another (or the same) software and/or hardware module for controlling communication with kill vehicles which have been dispensed by integrated payload. The software modules described herein can be used to maintain communication with a dispensed kill vehicle up to and after a time of predicted intercept when the dispensed kill vehicle is expected to intercept the threat. 
     With regard to the software module mentioned, the engagement management controller  212  can make real-time trade offs between using the integrated payload&#39;s limited propulsion resources to increase the burnout velocity of the payload and/or to expand the engagement space against a threat complex. As referenced herein, a “threat complex” is a group of objects, such as missiles, having re-entry vehicle(s), penetration aids, debris and so forth. The avionics and sensor control capabilities of the engagement management controller can be used to control upper stage propulsion (e.g., propulsion stage  206  and optionally the  FIG. 1  booster stages  102  and  104 ). As such, the engagement management controller  212  can perform navigation, guidance and control for the boost vehicle stages  102 ,  104  and  406 . Such integrated capability of the engagement management controller can reduce costs, mass and complexity of the overall interceptor system. 
     A software module of the engagement management controller  212  used for controlling propulsion resources can take advantage of the integrated payload, with its upper stage propulsion  206 , to enhance the payload delta-V. The engagement management controller  212  can leverage the increased delta-V in expanded performance and capability. For example, exemplary integrated payloads disclosed herein can dispense a group of kill vehicle assets to engage multiple threat objects, and then thrust to a new location to dispense additional kill vehicles associated with another portion of the threat complex. Such a capability is referred to herein as “bussing” and is attributable to enhanced capability of the integrated payload and its multiple kill vehicle assets. 
     The software module of the engagement management controller  212  for commanding dispensing of the plural kill vehicles can result in allocation of one or more kill assets to multiple targets in real time under the control and communication of the engagement management controller. As a result, the integrated payload  106  can achieve substantially enhanced effectiveness for multiple reasons. For example, due to on-board avionics and sensor control, the real time aspect of the integrated payload provide more accurate and current information as the integrated payload approaches a given target suite, such that the integrated payload can be guided to a more effective position for allocating kill vehicles to specific target assignments and manage system error sources. In addition, because the engagement management controller  212  includes a computer processor hosted on the integrated payload, as opposed to being located on the ground, targeting information can be provided to dispensed kill vehicles with reduced latency, thereby furthering increasing their effectiveness. For example, known sensor data can be acquired and processed on-board, without the added complexity of transmitting and receiving communications with respect to a ground controller. In addition to the foregoing advantages, a centralized control of the multiple kill vehicles in the integrated payload can allow an improved globally optional kill vehicle assignment to multiple targets and reduce asset wastage. Such capabilities can enable redundant robust fire control solutions. 
     A software module of the engagement management controller for maintaining communication with the kill vehicles, and for operating with only limited ground communications (e.g., for responding to a user initiated command and/or request for specific on-board data) can enable the integrated payload, as a single entity, to coordinate multiple target assignments. Communication between the carrier vehicle on the ground can be substantially reduced, thereby decreasing the demand for space-to-ground communication resources. This can reduce the size, mass and power of any communication subsystems associated with the carrier vehicle and/or the kill vehicles themselves. Because the integrated payload can maintain communications with kill vehicles throughout and beyond the engagement of a target, the integrated payload is able to collect, process and provide to the ground additional intelligence gathered immediately prior to, and after an intercept event. 
     In addition to the on-board engagement management controller  212 , the  FIG. 2  integrated payload  106  includes an integrated propulsion stage. An exemplary propulsion stage  206  of the illustrated integrated payload can include at least one fuel tank  216 . The plural kill vehicles  210  can be mounted to the kill vehicle release mechanism  208  about the fuel tank  216 . In the  FIG. 2  embodiment, the propulsion stage  206  can be a multistage rocket (MR)-80C mono-propellant thruster, and each of the kill vehicles  210  can include a mono-propellant or bi-propellant with or without energy on target (EOT) capability. In the embodiment shown, 16 kill vehicles are shown. However, those skilled in the art will appreciate that any number of kill vehicles can be accommodated given the desired capability and design constraints for the application specified. The fuel tank  216  can, for example, be a hydrazine tank of titanium construction. 
     Helium pressurant tanks  218  can be included of titanium construction for pressuring the fuel system. In an exemplary embodiment, four such helium pressurant tanks can be included for an integrated payload packaged within an Orbital Boost Vehicle (OBV)-2 or modified KEI 2 stage shrouds. 
       FIG. 3  shows an alternate embodiment similar to that of  FIG. 2  wherein like elements have been shown with like reference numerals. In  FIG. 3 , the propulsion stage  206  includes three monopropellant multistage rocket (MMR)-80 thrusters  302 . 
       FIG. 4  shows yet another embodiment wherein the propulsion stage  206  includes four bi-propellant thrusters  402 . In the  FIG. 4  embodiment, the fuel tank  216  can for example, be an monomethylhydrazine (MMH) fuel tank. As those skilled in the art will appreciate MMH is a volatile hydrazine chemical with the chemical formula CH 3 (NH)NH 2  used as a rocket fuel by propellant rocket engines and in hypergolic mixtures. The MMH fuel tank is designated  406 , and a separate fuel tank can be an oxidizer tank of N 2 O 4 . Again, both fuel tanks  404  and  406  can be of titanium construction. 
       FIGS. 5A-5C  shows an exemplary breakaway of the carrier vehicle  202  and payload adapter  208  of the  FIG. 2  embodiment. An exemplary embodiment includes a payload adapter  208  for a 16 kill vehicle capability. However, as those skilled in the art will appreciate, any Kill adapter mechanism and carrier vehicle can be configured to accommodate any desired number of kill vehicles. 
     Referring to  FIG. 5C , the carrier vehicle  202  includes a sensor bulkhead  502  for the sensor  214  of  FIG. 2 . A forward shell, such as a shell formed of a carbon fiber composite  504  serves as a mount for the sensor bulkhead  502 . An avionics bulkhead  506  is provided on a side of the forward shelf opposite that of the bulkhead. 
     The payload adapter  208  can include kill vehicle attachment rings  508  formed, for example, of aluminum. An aft shell  510 , formed for example, of a carbon fiber composite, supports the kill vehicle attachment rings. 
     A propulsion tank bulkhead formed, for example, of aluminum, and labeled  512 , is provided at an aft end of the aft shell  510 , and an aft bulkhead  514  is provided at a rear of the carrier vehicle. The complete assembly of the carrier vehicle is labeled  516 . 
     In  FIG. 5B , the carrier vehicle with the propulsion stage and sensor and avionics is labeled  518 . As shown in the assembly  518 , the sensor  520  and avionics  522  are located at a fore end of the carrier vehicle, and a propulsion stage  524  is located at the aft end mounted to the aft bulkhead. 
     In  FIG. 5C , the integrated payload with mounted kill vehicles is labeled  526 , and corresponds to the example illustrated in  FIG. 2 . 
       FIG. 6  shows the  FIG. 2  embodiment of the integrated payload within an exemplary OBV-2 stage and derived KEI 2 stage shroud labeled  603 . 
       FIG. 7  shows a perspective view from the nose direction of the integrated payload. The integrated payload  702  contains elements with like reference numerals as referenced in  FIG. 2 . 
       FIG. 8  shows an exemplary flow diagram of the operational flow characteristics of the engagement management controller  212 . The functional block diagram  800  includes an initial launch system block  802 . An exemplary method for controlling the payload for dispensing of multiple kill vehicles using the interceptor system of  FIG. 1 , includes controlling the propulsion of the carrier vehicle, and managing engagement of the kill vehicles with a threat using on-board guidance of the carrier vehicle. The engagement management allocates system propulsion resources among extending range and/or velocity of the carrier vehicle, and guiding the carrier vehicle to drop the kill vehicles to intercept a threat based on a controlled dispensing of the plural kill vehicles. The on-board sensing of a threat, and guidance to a threat, is represented by functional block  804 . 
     The engagement management module, or controller, manages propulsion resources in block  806  by assessing the number of identified threats detecting, calculating the distance to each within a given field of regard, and assessing the ability to engage each of the multiple threats for a given amount of fuel contained on the interceptor system. The engagement management module can determine the number of threats within the field of regard that the single interceptor system is able to engage through exploitation of lateral motion, balanced against extended range and/or velocity and number of kill vehicles in a direction to the threats. For example, the engagement module determines the largest number of threats which can be engaged in a given field of regard based on available fuel (e.g., destroy two near field, closely adjacent threats which are parallel to a current axis of flight, versus attempting to destroy two far field threats separated by a large distance along the current axis of flight). 
     In block  808 , kill vehicles are dispensed to address a specific target complex within a field of regard. In block  810 , communication is maintained with the kill vehicles to both guide the kill vehicles to the threat and receive communications regarding the kill vehicle engagement operation in real time. This information can be communicated to the ground in block  812  in any known fashion (e.g., in response to a user request and/or at specified periodic or aperiodic intervals). In decision block  814 , a decision is made as how-to manage the kill vehicles on-board the carrier vehicle. When kill vehicles have been dispensed and engaged their target, the mission is complete as represented by end block  816 . 
     Alternately, if kill vehicles remain on-board on the carrier vehicle, the engagement management controller guides the payload system to another threat in block  818 , and additional kill vehicles are dispensed to the threat in block  820 . Again, communication is maintained with dispensed kill vehicles in block  810  and carrier vehicle communication continues in block  812  until all kill vehicles have been dispensed. 
     It will be appreciated by those skilled in the art that the present invention can be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The presently disclosed embodiments are therefore considered in all respects to be illustrative and not restricted. The scope of the invention is indicated by the appended claims rather than the foregoing description and all changes that come within the meaning and range and equivalence thereof are intended to be embraced therein.