ABE Vehicle Characteristics
ABE is a three-body, open frame vehicle that
utilizes glass balls as flotation in two free-flooded upper
pods while the single, lower housing is host to the batteries
that power the vehicle and all of its electronics. This separation
of buoyancy and payload gives a large righting moment that simplifies
control and allows the vertical and lateral thrust propellers
to be located inside the protected space between the three faired
bodies. ABE has five thrusters allowing it to move in any direction.
It can travel forward at a cruising speed of 0.6m/sec, but one
of ABE’s most unique characteristics is that it can also
hover and reverse - characteristics that are particularly
valuable in the rugged terrain routinely encountered when investigating
the deep seafloor.
The navigation system onboard ABE consists of two proven and complementary navigation systems. For general use, ABE uses long “baseline” transponders identical to those used by Alvin and ROV Jason, and these allow deep seafloor surveys over distances of ~5km to be carried out. In addition, ABE also carries an acoustic Doppler velocity log (DVL) which provides short-range, high-precision navigation. With these navigation systems, ABE has the ability to follow tracklines with a repeatability of order 10m or better.