Hercules is a neutrally buoyant ROV that is used exclusively in conjunction with its mating vehicle, Argus, to which it is connected with a 30m length of neutrally buoyant tether. It is launched and recovered with the deck crane, generally over the side of the fantail.

Hercules is tethered directly to Argus during tandem ROV operations. It is the vehicle with the most maneuverability and is used for the most precise and delicate operations. Hercules is neutrally buoyant and is equipped with six thrusters that allow it to ‘fly’ in any direction, like a helicopter. Because the vehicle is slightly positively buoyant, it will gently float up to the surface if its thrusters stop turning.

Using its sensor array consisting of a pressure/depth sensor, altimeter, and Doppler, Hercules can conduct a variety of precision documentation functions. These can include: close-up visual inspection using its high definition video camera; surface sampling using its two manipulators that can place recovered samples into sample drawers or place them in elevators dropped to the bottom from the surface ship above; or precision acoustic and visual mapping of a site using its high-resolution sonars and/or digital stereo still cameras.

Hercules specifications

Weight in Air 5400 lb (2450 kg)
Weight in Seawater Neutrally Buoyant
Dimensions 11 long x 6 wide x 7.5 tall (3.4m x 1.8m x 2.3m)
Power 2400 VAC, 3 phase, < 20 kW
Depth Rating 4,000m (13,124 ft)