Abstract：To complete the sampling observation task in the mesoscale eddy region with underwater gliders platform, a cooperative control method for underwater gliders is proposed. Using the control method, underwater gliders can follow and sample the predefined circular trajectories with origin being the eddy center, and maintain any kind of predefined relative position during the sampling process. Firstly, the polar coordinate system is used for modeling the formation parameters of underwater gliders. Then the energy equation is constructed according to the formation parameters. Finally, the corresponding heading angle control law for underwater gliders is formulated by minimizing the value of differential function which is derived from energy function. Different trajectory parameters are investigated on the developed simulation system. Under the circumstances where the eddy center is moving with constant or varying velocity, underwater gliders can complete the sampling observation task of tracking circular trajectories with different radii in eddy region. The simulation results prove that the control method can satisfy the formation of gliders on the circular trajectories and provide an efficient approach to formation control for team observation and sampling task in ocean mesoscale eddy region.
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