Target Defense against Sequentially Arriving Intruders

Abstract

We consider a variant of pursuit-evasion games where a single defender is tasked to defend a static target from a sequence of periodically arriving intruders. The intruders' objective is to breach the boundary of a circular target without being captured and the defender's objective is to capture as many intruders as possible. At the beginning of each period, a new intruder appears at a random location on the perimeter of a fixed circle surrounding the target and moves radially towards the target center to breach the target. The intruders are slower in speed compared to the defender and they have their own sensing footprint through which they can perfectly detect the defender if it is within their sensing range. Considering the speed and sensing limitations of the agents, we analyze the entire game by dividing it into partial information and full information phases. We address the defender's capturability using the notions of engagement surface and capture circle. We develop and analyze three efficient strategies for the defender and derive a lower bound on the capture fraction. Finally, we conduct a series of simulations and numerical experiments to compare and contrast the three proposed approaches.

Target defense against a sequentially arriving cooperative intruder team

“…20 Later, the optimal waiting strategy and the corresponding optimal engagement strategy was derived. 17 In the following, we summarize these results and discuss defender's capturability for a given intruder. x A (t 0 +τ eng )…”

“…The derivation of the motion strategy for each intruder is based on our prior work. 17,18 Let x A (t), x D (t) ∈ R 2 denote the positions of an intruder and the defender at time t (we will refer to the intruders and the defender as agents in the paper). Both the defender and a generic intruder are assumed to have first-order dynamics, i.e.,…”

“…In our prior work, 17 we studied a target-defense problem where a single defender was tasked to capture a sequence of incoming intruders before they reached the target. The intruders appeared randomly on the perimeter of a fixed circle surrounding the target and were equipped with sensors with finite range.…”

“…We analytically quantified the percentage of capture for both finite and infinite sequences of incoming intruders. Later we extended this work 18 and studied the targetdefense problem with a sequence of periodically arriving intruders. We developed and analyzed three efficient strategies for the defender and derived a lower bound on the capture fraction.…”

Optimal Intermittent Sensing for Pursuit-Evasion Games

“…The waiting behavior has proven to be a crucial characteristics in some of the recent works involving sensing limited pursuit-evasion games [14,19,20].…”