How It Works-Amazing Vehicles

vapour and sweat from the pilot into a special bag,

which could be drunk in an emergenc y.

Other t y pes of undersea robots are capable of

guiding themselves, after being programmed, to

carr y out a task. These are know n as AU Vs, or

autonomous underwater vehicles. This kind of

mini submarine is used for scanning larger areas

of the ocean, as AUVs are able to work for much

longer than a manned sub and dive much deeper

than an ROV.

One such dev ice is Nereus, ow ned by WHOI. This

is a HROV, (H for Hybrid). The robot can be

programmed to venture off alone and scan the sea

fl oor using sonar mapping and camera systems; if

it fi nds anything interesting it can then be

returned to the site v ia a light weight tether and

equipped with extra sampling apparatus at the

command of scientists aboard the ship.

A similar method is usually used for other,

smaller AUVs such as Bluefi n-21, developed by

Bluefi n Robotics. This AU V is capable of mapping

the sea fl oor using echo sounders and side-scan

sonar for up to 24 hours. GPS systems then return it

to a parent ship, where the data is then analysed

by the scientists.

If anything of interest is found, Bluefi n-21 can

return to the exact site with high-resolution

imaging gear on board to give scientists a closer

look. A longside the external features,

submersibles and ROVs require a whole host of

other technolog y on board.

The deepest realms of the ocean are pitch black,

so most submersibles and ROVs have powerful

lights to provide illumination in the depths. These,

as well as everything else on the sub, are battery

powered. The batter y life of a sub governs exactly

how much ‘bottom time’ is allowed, alongside the

ascent and descent rates. Many submersibles still

use lead-acid batteries in their power cells, but

lithium-ion is now being introduced into many.

Stage II of A lv in’s latest upgrade is set to see the

inclusion of lithium-ion batteries to extensively

improve the sub’s bottom time.

Typical manned submersibles will have an

on-board computer to log data and monitor all

electronic systems. As well as GPS and

navigational tracking systems, sonar,

communications apparatus (Cameron’s record-

breaking sub could even send text messages), subs

and ROVs will also have many different sensors to

monitor the parameters outside the craft and send

the data back for analysis in real time. Many

submersibles and ROVs can also be fi tted with all

kinds of specialised equipment, depending on the

task that it is set to accomplish.

Take the plunge into a story of the ever-

increasing depths humans have reached

History of deep-sea explorers

(^1) Deepsea
Challenger
10,908m (35,787ft)
(^6) Alvin
4,500m (14,764ft)
(^11) Johnson Sea
Link
914m (3,000ft)
(^16) Sentry
6,000m (19,685ft)
(^2) Exosuit
305m (1,000ft)
(^7) Bluefi n-21
4,500m (14,764ft)
(^12) Seaeye Lynx
ROV
1,500m (4,921ft)
(^17) MIR DSV
6,000m (19,685ft)
(^3) Virgin Oceanic
11,034m (36,201ft)
(expected)
(^8) Shinkai 6500
6,500m (21,325ft)
(^13) Deep Worker
3000
1,000m (3,280ft)
(^18) Nautile
10,902m (35,768ft)
(^4) SonSub
Innovator
3,000m (9,843ft)
(^9) Kaiko 7000II
7,000m (22,966ft)
(^14) Magnum Plus
3,962m (13,000ft)
(^15) Hercules
4,000m (13,123ft)
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SEA