Control systems for ROVs have seen considerable development over the last decade to meet the requirements to perform more tasks or to reduce the operator work load. Heading and depth can be automatically controlled in sea currents and under the influence of other disturbances. Similarly, the position of a vehicle can be controlled automatically within the constraints of a long base line or short base line navigation system. Sophisticated work packages for inspection and maintenance tasks do exist and are in daily operation. However, they tend to become clumsy and imprecise when operated manually from a remote station.

With the current generation of vehicle systems with their work packages, including tele-operated manipulators and so on, one may well raise the question, why is there a need to develop Intelligent Control and if there is a need, when will it be reliable or indeed essential?

Intelligence implies additional levels of control, capable of interpreting sensed information and making decisions based on that information in the presence of uncertainty. The feasibility of fully automated inspection or maintenance tasks have been demonstrated. The first steps toward automatic classification of surfaces or sediments and the recognition of objects from sonar images have also been taken.

Television images can be transmitted over acoustic communication links. These techniques can enhance the performance of the next generation of advanced robotic ROVs for deep water, long duration tasks or for exploration.

Many question remain. Do we need underwater machines with an intelligent capability? Can we encapsulate sufficiently robust artificial intelligence into a relatively small machine? Who will fund their development? What new markets will they open up? Can we do without them? When could they be available?

The discussion in this brief paper will not answer these questions. All that can be achieved is to raises the awareness of the current state of the technology for intelligent control systems and outline the experience gained from a number of experiments. The answers will evolve as the needs become better understood and the technologies become more robust.

The Evolution of ROV systems

The nature of the sea and the sub-sea environment has fascinated man for centuries, but only in recent years has he been able to explore the deep oceans and exploit the mineral deposits beneath the sea floor. The sea has provided both a natural defence and a source of attack in military terms. It has been used to provide food and has been polluted by the indiscriminate disposal of incredibly dangerous waste materials.

Further exploitation of the resource from the sea is inevitable and hopefully, replenishment and careful stewardship of our environment will provide for man for centuries into the future.

With this background, the development of remotely operated vehicle technology has progressed in a manner dictated by market opportunity, primarily in the offshore oil and gas industry. As the inspection, repair and maintenance of offshore a structures and equipment has taken on a more demanding role with the maturing of the offshore industry, so the complexity of task.

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