Pursuit Evasion Strategies for Missile Defense

RT&L FOCUS AREA(S): Hypersonics TECHNOLOGY AREA(S): Air Platform; Information Systems; Battlespace; Weapons The technology within this topic is restricted under the International Traffic in Arms Regulation (ITAR), 22 CFR Parts 120-130, which controls the export and import of defense-related material and services, including export of sensitive technical data, or the Export Administration Regulation (EAR), 15 CFR Parts 730-774, which controls dual use items. Offerors must disclose any proposed use of foreign nationals (FNs), their country(ies) of origin, the type of visa or work permit possessed, and the statement of work (SOW) tasks intended for accomplishment by the FN(s) in accordance with section 3.5 of the Announcement. Offerors are advised foreign nationals proposed to perform on this topic may be restricted due to the technical data under US Export Control Laws. OBJECTIVE: Support hypersonic threat interception by developing battle management and advanced guidance and control algorithms based on differential game theory, continuous pursuit/evasion concepts, control theory, and optimization methods. DESCRIPTION: The subsequent trajectory and aim point of a detected and tracked hypersonic threat is indeterminate, although subject to constraints, due to either pre-programmed maneuvers (unknown in advance to the defense) or real-time evasion by the threat from a threat-detected interceptor. Application of state-of-the-art pursuit-evasion strategies to battle management and to guidance and control processes could increase the likelihood of successful defense. Key output of the objective computational capabilities is optimal interceptor launch scheduling and dynamic behavior in flight (i.e., the interceptor flight plan to be updated in useful real time during the engagement). Expected collateral outputs include optimal (from the offense point of view) threat behavior and a collapsing map of possible threat impact points. The computational framework should be capable of real-time solution, and be suitable for execution at the battle management node and, optimally, onboard the interceptor(s). The objective of this topic can be further described by considering the scenario-imposed constraints on both the defense/pursuer/interceptor and on the offense/evader/threat: The underlying assumption is that the evader (the offensive threat), has two objectives: (i) maneuver to evade interception by the defense, and (ii) conserve sufficient momentum and energy to reach the target (or alternatively, another high-value target). Model constraints for the offense may include threat missile performance capabilities, target/target-set selection, degree of offense knowledge/assumptions about defense-asset capabilities, and capacity for sensing of defensive interceptor maneuvers. One special case is where the offense pre-programs the threat target with a pre-determined evasive trajectory, but does not update that trajectory based on real time tracking of the interceptor. A parallel underlying assumption is that the pursuer (defense) has the objective of denying either one of the two offense objectives, i.e. to either achieve intercept or to force the threat to exhaust its energy capability to reach target range due to evasive maneuvers. Model constraints for the defense may include interceptor performance, interceptor inventory, threat acquisition and tracking accuracy, knowledge/assumptions about the threat capability and intention, and defended asset relative values. Primary near-term application is in defense against boost/glide-type offensive hypersonic weapons, and for interception during the threat mid-trajectory glide phase. PHASE I: Develop computational algorithms for the differential game with limited constraints using nominal trajectories. This phase should focus on 1-on-1 simulation (one pursuer and one evader). The scenario could utilize a single interceptor at a certain location and a single threat with one target. Algorithm outputs could be battle management, optimal launch scheduling, and optimal guidance onboard the interceptor. Evaluate feasibility compared to traditional guidance, navigation and control (GNC) with nominal data. PHASE II: Enhance computational capability with increased functionality. This could also include the possibility of government supplied information. A missile defense system insertion opportunity should be identified. Work with a potential system integrator. Evaluate effectiveness compared to traditional GNC. PHASE III DUAL USE APPLICATIONS: Develop fire control and guidance algorithms based on Phase II results, suitable for insertion into an operational battle manager and/or interceptor GNC (guidance, navigation and control). Work with system integrator to develop roadmap for actual insertion into an operational system. Productize the tool to expand capabilities to other military applications. REFERENCES: 1. Differential Games: A Mathematical Theory with Applications to Warfare and Pursuit, Control and Optimization, Rufus Isaacs, John Wiley and Sons, 1965. ; 2. Mauro Pontani and Bruce A. Conway , Numerical Solution of the Three-Dimensional Orbital Pursuit-Evasion Game 1. J. of Guidance, Control and Dynamics, Vol. 32, No. 2, 474 487, March April 2009 https://arc.aiaa.org/doi/10.2514/1.37962 ; 2. Mauro Pontani and Bruce A. Conway , Optimal Interception of Evasive Missile Warheads: Numerical Solution of the Differential Game , 3. J. of Guidance, Control and Dynamics, Vol. 31, No. 4, 1111 1122, July Aug 2008. https://arc.aiaa.org/doi/10.2514/1.30893