A bottom crawler is an underwater exploration and recovery vehicle. It is designed to sink to the bottom of a body of water, where it moves about using traction against the bottom with

wheel A wheel is a circular component that is intended to rotate on an axle bearing. The wheel is one of the key components of the wheel and axle which is one of the six simple machines. Wheels, in conjunction with axles, allow heavy objects to be ...

s or tracks. It is usually tethered to a surface ship by cables providing power, control, video, and lifting capabilities, but this is not essential. Such devices have been proposed for use in recovering deep seabed minerals, such as

manganese nodules Polymetallic nodules, also called manganese nodules, are mineral concretions on the sea bottom formed of concentric layers of iron and manganese hydroxides around a core. As nodules can be found in vast quantities, and contain valuable metals, de ...

. These also have been considered since the late 1960s for use in offshore

oil exploration Hydrocarbon exploration (or oil and gas exploration) is the search by petroleum geologists and geophysicists for deposits of hydrocarbons, particularly petroleum and natural gas, in the Earth Earth is the third planet from the Sun ...

and production in extremely deep water, but practical devices have used other technologies from the sea surface, such as moored barges and

tension leg platform __NOTOC__ A tension-leg platform (TLP) or extended tension leg platform (ETLP) is a vertically geotechnical engineering#Floating-moored structures, moored floating structure normally used for the offshore production of crude oil, oil or natural g ...

References

Oceanography {{Ocean-stub