Submersible Acoustic Navigation for Precise Underwater Surveys

With submersibles playing an increasingly important role in the offshore oil industry for performing surveys and inspections, rapid, accurate positioning becomes imperative. The ability to accurately navigate and record track and survey data is vital to a successful survey. Until recently, size and cost constraints made navigation equipment in the submersible impractical, so tracking of submersibles was done on the surface, and the pilot guided via underwater telephone. Now based upon microprocessor technology and past acoustic navigation experience, Sea-Link Systems has developed a miniaturized navigation system which fits inside a manned submersible and provides navigation data directly to the pilot. Using data from the acoustic ranging system, a doppler velocity sensor and compass, the system provides the pilot with course-line navigation guidance to precisely cover a pre-determined grid survey pattern allowing the pilot to complete his survey with greater accuracy and speed.