Date of Award
7-2017
Document Type
Dissertation
Degree Name
Doctor of Philosophy (PhD)
Department
Department of Aeronautics and Astronautics
First Advisor
Richard G. Cobb, PhD
Abstract
Optimal control theory is applied to the study of missile evasion, particularly in the case of a single pursuing missile versus a single evading aircraft. It is proposed to divide the evasion problem into two phases, where the primary considerations are energy and maneuverability, respectively. Traditional evasion tactics are well documented for use in the maneuverability phase. To represent the first phase dominated by energy management, the optimal control problem may be posed in two ways, as a fixed final time problem with the objective of maximizing the final distance between the evader and pursuer, and as a free final time problem with the objective of maximizing the final time when the missile reaches some capture distance away from the evader.
These two optimal control problems are studied under several different scenarios regarding assumptions about the pursuer. First, a suboptimal control strategy, proportional navigation, is used for the pursuer. Second, it is assumed that the pursuer acts optimally, requiring the solution of a two-sided optimal control problem, otherwise known as a differential game. The resulting trajectory is known as a minimax, and it can be shown that it accounts for uncertainty in the pursuer's control strategy. Finally, a pursuer whose motion and state are uncertain is studied in the context of Receding Horizon Control and Real Time Optimal Control. The results highlight how updating the optimal control trajectory reduces the uncertainty in the resulting miss distance.
AFIT Designator
AFIT-ENY-DS-17-S-055
DTIC Accession Number
AD1055573
Recommended Citation
Carr, Ryan W., "Optimal Control Methods for Missile Evasion" (2017). Theses and Dissertations. 3692.
https://scholar.afit.edu/etd/3692