Flow-Based Rendezvous and Docking for Marine Modular Robots in Gyre-Like Environments

Modular self-assembling systems typically assume that modules are present to assemble. But in sparsely observed ocean environments modules of an aquatic modular robotic system may be separated by distances they do not have the energy to cross, and the information needed for optimal path planning is often unavailable. In this work we present a flow- based rendezvous and docking controller that allows aquatic robots in gyre-like environments to rendezvous with and dock to a target by leveraging environmental forces. This approach does not require complete knowledge of the flow, but suffices with imperfect knowledge of the flow’s center and shape. We validate the performance of this control approach in both simulations and experiments relative to naive rendezvous and docking strategies and show that energy efficiency improves as the scale of the gyre increases.