Researchers at the U.S. Naval Research Laboratory (NRL) are working on designing and developing a novel underwater propulsion, control, and sensing solutions for near-shore and littoral zone missions.
Autonomous underwater vehicles (AUVs) have demonstrated many successful capabilities in inspection, surveillance, exploration, and object detection in deep seas, at high speeds, and over long distances. However, operations in littoral zones requiring low-speed and high-maneuverability present mobility and sensing challenges that have not been satisfactorily resolved.
Jason Geder, aerospace engineer, Laboratories for Computational Physics and Fluid Dynamics at NRL, said:
Expeditions in near-shore environments are complex, often proving turbid, cluttered with obstacles, and plagued with dynamically changing currents.
Inspired by the pectoral fins of the reef fish, bird wrasse, NRL researchers have developed an actively controlled curvature robotic fin that provides scaled down AUVs a novel low-speed propulsion system.
WANDA is designed to operate at speeds in excess of two knots, or hold position in the presence of two-knot currents, giving it the propulsion and control authority needed in many harbor and other near-shore operational zones. WANDA can also successfully coordinate maneuvers to achieve waypoint navigation.
As the Navy’s focus on autonomy and unmanned systems intensifies, NRL’s bio-inspired research into capable propulsion and control technologies for low-speed operation in near-shore environments is helping to close a clear gap in AUV technology. An unmanned vehicle that can effectively operate in these areas, where traditional platforms experience stability and control problems, will improve performance for critical missions including harbor monitoring and protection, hull inspection, covert very shallow water operations, and riverine operations.
Image: U.S. Naval Research Laboratory