The underwater robot Observer 3.2 is an ultra light weight vehicle (14.5 lbs), only 19.7 inches long, with yet outsanding performances in terms of navigation and inspection.
It can reach 500 feet water depth, and a speed of 3 knots. In its standard version, it is equipped with two high definition/high sensitivity cameras, and can carry, in addition, a mini sonar (Tritech Micron DST or equivalent), a 2 functions manipulator, and many others sensors and tools thanks to its accessory plug.
The ROV and its console are equipped with embedded batteries, which allow to operate them up to 4 hours without external power. The system can also be run on main power.
The whole equipement (vehicle, control console and umbilical) is contained in one single water proof case, on wheels, with a total weight of 45 lbs.
https://www.youtube.com/watch?v=VKsIBcgFqc0
[mappress] March 29, 2013; Image: Subsea Tech