Autonomous Benthic Explorer

Lore & Background

After hydrothermal vents were discovered using DSV Alvin in 1977, significant scientific interest arose in returning to previously surveyed vent sites. Since DSV Alvin was highly sought after, WHOI developed several uncrewed platforms that could perform similar missions without a human operator. ABE consisted of three torpedo-shaped hulls arranged in a shape similar to the fictional Starship Enterprise. The upper two hulls each contained three glass spheres to provide buoyancy, while the lower platform contained the batteries, navigation equipment, and mission sensors. Five independent thrusters allowed for three-dimensional maneuverability at speeds up to 1.4 kts. ABE used a long baseline acoustic positioning system to navigate a pre-programmed route along the seafloor.

ABE was developed by WHOI in 1994 and participated in its first mission during the summer of 1996, where it was used to create sonar and magnetic maps of a subsea lava flow on the Juan de Fuca ridge in the Eastern Pacific. During this first mission, ABE retained an umbilical cable to the deploying research vessel but navigated autonomously back and forth over the lava flow. From 1999 to 2006, ABE conducted wide area mapping of regions with known hydrothermal vents (such as the Southeast Pacific Rise) and identified many additional vents. Its first truly autonomous mission did not occur until 2000, when researchers deployed ABE to survey one site, left for a different site 30 mi away, then returned to recover ABE when it had finished its survey. By 2004, ABE demonstrated a capability to autonomously detect and localize a hydrothermal vent using the chemical concentration of the vent's plume.

ABE was lost during its 222nd mission on March 5, 2010, at a depth of 3000 m. At the time, the research vessel USNS Melville was using ABE to map and photograph a hydrothermal vent site near the Chile triple junction. Operators believe that one of the six glass spheres used to provide buoyancy catastrophically failed, leading to the sympathetic detonation of the remaining five spheres. ABE is not believed to be recoverable.

Reader's Guide

ABE demonstrated the capability of an AUV to perform long-duration mapping and sea floor survey missions and spawned a series of deep-diving AUVs. It is now rare for oceanographic teams to deploy a crewed deep submergence vehicle without first using an AUV to survey the area and determine the best site to visit. WHOI developed a direct successor to ABE, the AUV Sentry, which saw extensive use in assessing the damage caused by the Deepwater Horizon disaster. ABE's legacy includes proving that a relatively simple autonomous vehicle could effectively scout for more sophisticated crewed or remotely operated platforms, changing the standard workflow for deep-sea exploration. Its design and operational success influenced later vehicles such as the REMUS 6000 and Autosub Long Range, which share a similar configuration.

Did You Know?

• ABE was designed to perform wide-area seabed surveys at depths of up to 4500 m.
• ABE completed 222 missions from 1996 until it was lost at sea in 2010.
• Its first truly autonomous mission occurred in 2000, when researchers deployed it at one site, left for a site 30 mi away, then returned to recover it.