Capturing a Faster Evader by Some Energy-Limited Speed-Controllable Pursuers

Multiagent pursuit-evasion problems have been widely investigated in a number of related areas. In many situations, the pursuers have energy limitation when pursuing the evader, and the pursuers moving at higher speeds consume energy more quickly. The energy limitation creates two problems for the pursuers. First, constantly moving at the maximum speed is not optimal because the energy will be exhausted quickly. Therefore, it is necessary to control the speed to achieve the optimal energy consumption, but previous studies have not presented a suitable speed-control algorithm. Second, a fraction of pursuers with insufficient energy may fail to complete the sub-tasks, and the evader can vary the escape strategy by considering the energy limitation of the pursuers. Therefore, the pursuers with sufficient energy need to help the pursuers with insufficient energy and address the variety of the evader's escape strategy. The existing pursuing strategies are not self-adaptable to satisfy this requirement. In this paper, we present a pursuing strategy consisting of both a speed-control algorithm and a path planning algorithm as sub-algorithms. Additionally, we integrate the subalgorithms into a self-adaptable cooperation strategy based on simulated annealing, which makes the pursuers adaptably help each other and is adaptable to the variety of escape strategies. The experimental results show that our strategy leads to higher capture success ratios than previous strategies when the energy of pursuers is limited. The experimental data also show that our strategy is more adaptable to the variety of the pursuers' maximum speed and the variety of the evader's escape strategies.