Cooperative Constrained Enclosing Control of Multirobot Systems in Obstacle Environments

This article develops a novel cooperative constrained control framework to solve the moving-target enclosing problem for multirobot systems, where safe navigation and formation precision are concerned in obstacle environments. When moving obstacles block the encircling motion, the enclosing formation contracts toward the target with a precise spacing pattern. Without a priori knowledge of environmental information, the mobile robot group can track and enclose a moving target while guaranteeing limited sensing requirements and collision avoidance with the target, neighboring robots, and obstacles. Under the precision constraint, with an encircling speed assigned to only one robot, the mobile robots are driven by their neighbors until all robots enclose the target as a whole. With the help of velocity observers, the robot group can converge to a small neighborhood of the desired enclosing formation without knowing the target's velocity. Simulation results demonstrate the effectiveness of the proposed constrained control strategy.