Optimal group structure for group chase and escape

Chasing multiple escapees by a group of chasers is an important problem for many living animal species and for various agent systems. On this group chase problem, it has been reported that having two distinct types of chasers in the group, namely diligent and totally lazy chasers, can improve the efficiency of the group of catching all the targets. In this paper, we search for a better group structure by letting each agent have moderate laziness. We find that there exists an optimal group structure, which performs better than the previously reported group which consists of binary (fully diligent and totally lazy) types.