New hybrid underwater vehicle prototype unveiled

By Curious

Makai Ocean Engineering, Inc. and the University of Hawaii (UH) have joined forces and managed to develop an innovative autonomous underwater vehicle (AUV) that is able to efficiently deploy seafloor sensor equipment via an intricate combination between free-swimming AUV features and those of a bottom crawling vehicle.

The name chosen for this new “hybrid” autonomous underwater vehicle is Bottom-Skimming AUV or B-SAUV for short. Its propulsion system consists of thrusters but it is also able to touch, glide along and fully interact with the ocean floor.

What makes this underwater vehicle unique lays in the fact that it can autonomously adjust its wet weight (by dynamically regulating its buoyancy) and thus manage the manner in which it interacts with the seafloor. It moves through the ocean via its thruster-based propulsion system and operates in three separate buoyancy modes:

1) Low Buoyancy: the vehicle presses on the seafloor using its full wet weight,

2) Medium Buoyancy: the vehicle lightly ‘skims’ along the ocean floor at a fixed wet weight (in order to provide the necessary adjustments for existing seafloor conditions), and the third mode being -

3) High Buoyancy: The vehicle ‘flies’ for a short period of time above the seafloor in the water column so that it could overcome the obstacles among its pathway.

The B-SAUV is managed via a computer hardware and software system which along with autonomously regulating buoyancy, gives it also the ability required to navigate autonomously to a predefined location and install (and log data from) oceanographic sensors in the ocean floor. These sensors are located within the body of the B-SAUV and can be employed for environmental monitoring as well as remote sensing.

Makai and UH had begun working on the concept, designs, fabrication, and testing of the prototype B-SAUV way back in 2011. The most recent development regarding the project came in November 2014, when Makai and UH managed to complete a successful at-sea test and demonstrate the full specter of capabilities regarding the prototype vehicle. The test served as validation for the operation of all critical subsystems and B-SAUV controls.