Energy Efficient AUV Using a Lateral Line Sensor

This project seeks to provide substantial energy savings to Autonomous Underwater Vehicles by using MEMS-based pressure sensor arrays to sense the vehicle’s flow environment. AUVs will be able to continuously adjust their position using feedback control algorithms and hydrodynamic control procedures. The system mimics the way fish sense and respond to hydrodynamic conditions while swimming. If successful, this work has the potential to revolutionize the vessel-design industry.

Objectives: To develop the capability to save substantial amounts of AUV propulsive and maneuvering energy, through sensing the vehicle’s surrounding flow environment using MEMS-based pressure sensor arrays, and employing effective feedback control algorithms and hydrodynamic control procedures to adjust vehicle attitude, vehicle position, and the surrounding flow field.
To demonstrate experimentally the energy savings through the use of a vehicle model in the propeller tunnel.

Methodology: The work will be conducted experimentally in the propeller tunnel using a vehicle model that can be rotated through a motor within an oncoming flow. MEMS-based sensors will provide the pressure sensing capability, while algorithms based on principal component analysis will provide the essential signature features that allow rapid recognition of flow separation extent and location, and feedback laws to minimize their effects. The project will develop energy saving procedures based on optimally arranged, sparse sensors. Also, active flow control procedures will be tested experimentally using techniques developed for flow management in the offshore and airline industries.

Rationale: The project will provide a unique capability to save energy in autonomous underwater vehicles, by emulating the capability of live fish to sense their environment through their lateral line and control their position and the flow around them.

AUVs, like fish, are streamlined longitudinally to minimize resistance. When operating in an ocean environment, however, with side currents, waves and turbulence, or when they maneuver, they waste energy as their non-streamlined cross-section causes the flow to separate, developing large drag forces.
We have developed recently MEMS-based pressure sensor arrays that provide a unique capability to emulate the lateral line of fish. We have also developed hydrodynamic algorithms that can be adapted to identify separated flow, hence allowing the development of algorithms to continuously optimize the vehicle performance and save substantial energy, allowing longer operation. This is a capability that is expected revolutionize the marine industry as it will allow continuous monitoring of the hydrodynamic performance of vehicles and their subsystems.