A hydrodynamic drag-modulation
system for six-degrees-of-freedom (6-DoF)
dynamic positioning (DP) of deep-sea payloads—including
station-keeping and controlled translation of very large, submerged bodies—is introduced, wherein a distributed
underwater swarm of vector-drag generating drones (tethered autonomous
underwater vehicles or T-AUVs) leverages coordinated multi-agent control, independent of surface DP vessels and
surface conditions. By commanding tether-retraction velocity and geometry of the drag-inducing elements, each
drone agent functions as a virtual, relocatable bollard in three dimensions. Collectively, the swarm forms a virtual, dynamic dock around the
payload, enabling both precision DP operations and long-range deep-
sea transport missions. Furthermore, due to the non-propulsive, drag-modulation-based actuation principle, the
system is inherently configurable for
cavitation-free operation, thus suitable for industrial or scientific operations requiring low-acoustic-signature. By treating hydrodynamic drag as a programmable, distributed
actuator, the
system achieves surface-independent 6-DoF control, providing fault-tolerant, high-precision manipulation and transport under conditions where conventional DP systems fail.