Cooperative fishing pursuit strategy for encirclement of a faster evader: theory and application

This paper presents a Cooperative Fishing Pursuit Strategy (CFPS) for addressing the challenge of encircling a faster evader using multiple pursuers in a two-dimensional open domain. Firstly, based on the barrier of the fishing game, we formulate a problem model for multi-pursuer cooperative encirclement of a fast evader, transforming it into two velocity design problems in mutually orthogonal directions: one that regulates the angles between adjacent pursuers (perpendicular to the line of sight), and another that controls the distance to the evader (along the line of sight). Secondly, an adaptive approach is employed to design each pursuer's velocity in the perpendicular direction, with a Lyapunov stability proof showing that the included angles converge exponentially to a prescribed interval under this strategy. Thirdly, we design the velocity in the line-of-sight direction and select a referenced distance to ensure that the pursuers continually approach the evader while meeting the encirclement requirements. Finally, numerical simulations and experiments validate the effectiveness of the CFPS across various scenarios, including those in which the evader adopts passive strategies, moves in a fixed direction, or actively avoids the pursuers. The results demonstrate that CFPS not only guarantees successful encirclement but also provides a theoretical foundation for designing and analyzing pursuit behaviours in multi-agent systems.