Underwater vehicles are tethered or autonomous, manned or unmanned Tethered work systems, whether remotely operated or manned, have the advantage of unlimited surface-supplied power, but are limited in range by the length of their cables to a support vessel or surface platform Such systems include nearly 70 vehicles that have been operated successfully during the past decade, including 15 Jims, 18 Wasps, 30 Mantis submersibles, two Wranglers and two Spiders While autonomous in terms of life support, all typically rely on a tether for launch and recovery as well as for primary power and communications. Complete autonomy is normal for large manned submersibles, but it is largely atypical for atmospheric diving systems (ADS), microsubmersibles such as Mantis, and for most remotely operated vehicles (ROVs) This changed with the advent of the autonomous one-person microsubmersible, Deep Rover (Fig 1), and subsequently, the smaller, wider-ranging Deep Flight (Fig 2) A description follows of the development and application of these systems.
Deep Rover was designed to incorporate desirable features of large submersibles, including autonomous operation and increased range and depth capability, in a small, transportable system that, like an ADS, could be piloted by diverse operators with relatively little training at a cost significantly lower than that required for larger, more complex systems.
The senior author, designer of Wasp, Mantis and various ROVs, set out to produce a submersible that is user friendly so that the operator can concentrate on the work at hand while comfortably managing and operating the submersible Success in achieving this goal can be measured in part by the time required to master basic operational procedures-about 30 minutes In a seated position, the pilot exerts slight forward motion on one or both arm-rests Microswitches in the arm-rests activate appropriate thrusters and the sub moves forward, reverse is triggered by leaning back Such movements soon become instinctive and most of the pilot's attention can therefore be concentrated on working. (Fig.1 is available in full paper)The effect is in some ways comparable to SCUBA diving in terms of spontaneity of action, dexterity and manoeuverability-but without the burden of decompression nor with the complexities typically involved with piloting a small submersible. Such ease of operation is taken for granted by astronauts with moon-walking or space-walking suits, as well as by divers, but it is not often considered in autonomous submersibles. Most require a dedicated pilot, with work performed primarily by one or more crew.
Deep Rover's man/machine interfacing relates directly to its ADS heritage, where the concept of the vehicle behaving as an extension of the operator to perform work is fundamental to the commercial success of the system. One indication of the ease of operation is the number of who have served as pilots. Within the first two years of operation, Can-Dive Services Limited (Deep Rover's owners and operators), logged 165 working dives involving 80 different operators. An additional 100 + short, shallow dives were made by individuals ranging from the son and daughter of the designer (at ages 13 and 14) to a retired British admiral.