The collaborative formation problem of robots is a comprehensive research topic，which mainly includes two stages：formation strategy and path planning. To solve the problem of collaborative formation capture of targets in multiple biomimetic robot systems in underwater environment，a security domain negotiation capture strategy based on an improved ant colony algorithm is proposed to address the energy constraints of a single robot executing tasks in an unknown underwater environment. After discovering the target during the robot's random search process，a secure domain negotiation strategy is used to allocate capture points around the target robot. An improved ant colony algorithm is used to realize path planning and adaptive obstacle avoidance during the formation process. Simulation experiments are conducted in obstacle environments of different sizes，and compared with classic path planning algorithms. The experimental results show that the proposed strategy can enable robots to complete efficient collaborative formation capture tasks in complex underwater obstacle environments，and it is effective.
