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This paper describes the various development phases and the associated hurdles faced during the design, fabrication, sub-system level testing, assembly, integration and overall system testing of an Autonomous Underwater Vehicle (AUV). This AUV has been designed for a depth of 150 m with multi-thruster actuation for shallow water applications. The AUV is having onboard power, electronics and advanced control module, navigation and payload sensors and modular software architecture. During the development of AUV various hurdles like how to power on AUV from outside, loose connections, isolation and grounding, water leakage, battery tripping, etc. have been faced and resolved. The present paper describes the complete development aspects in brief and highlights the various hurdles with remedies throughout the development. The AUV has been tested successfully for various missions at Idukki Lake, Cochin, India up-to a depth of 5m. [ABSTRACT FROM AUTHOR]

The aim of this paper remains to introduce the various design and runtime aspects of a state-of-the-art control architecture adopted for the development of an autonomous underwater vehicle (AUV-150), capable of operating up to a depth of 150 meters to perform sea-bed mapping and collecting oceanographic data. The system control architecture has been presented as an ensemble of both hardware and software modules organized in a well-connected framework for effective operation. Various specifications, harnessing layout and design issues have been discussed in this paper. [ABSTRACT FROM AUTHOR]

Advances in technologies related to miniature sensors, memories, embedded controllers, power systems and materials has resulted in development of variety of autonomous underwater platforms for ocean exploration. The future in oceanographic instrumentation is intelligent small Autonomous Underwater Vehicles (AUV΄s), autonomous profilers, gliders [1], etc. The ultimate aim in all autonomous platforms research and development is to reach the stage of unescorted missions with minimum failures. This stresses for implementation of multiple safety measures of a high degree so that the platform operates continuously in a fail-safe mode. This paper discusses issues on safety measures implemented on the autonomous underwater platforms namely MAYA AUV and the Autonomous Vertical Profiler [AVP] developed at NIO, Goa. The safety aspects in Design & Construction, Operations, Monitoring and Emergency have been addressed. [ABSTRACT FROM AUTHOR]

The work presented in this paper describes an algorithm for underwater mapping and localization in a confined environment, which are two major issues for autonomous underwater vehicles' navigation. The proposed procedure consists of the application of mathematical morphology image segmentation and least squares curve fitting. A mechanically scanned imaging sonar is used to represent the surroundings of the vehicle. Experimental data were collected in an elliptical test tank. The algebraic map is finally constructed according to the acoustic images. Results indicate a good and fast performance of the proposed algorithm. [ABSTRACT FROM AUTHOR]

Near-bottom groundfish communities were surveyed in the waters off California and Oregon using the Seabed autonomous underwater vehicle (AUV) at depths ranging from 100 to 500 m. These surveys were designed to test the utility of the Seabed AUV in surveying groundfish and their associated habitat. The long-term goal of these tests is to fill the need for cost-effective, non-extractive, fishery-independent surveys in untrawlable areas. During nine dives we collected information on the species composition, abundance, and size of many groundfish species, and over 30,000 images were collected from the optically calibrated camera. Habitat classification on a fine spatial scale was easily accomplished and allowed habitat associations of many species to be determined. An assessment of one of the most easily identifiable species, rosethorn rockfish Sebastes helvomaculatus, also showed that the size composition of this species varied over habitat types. These surveys were the first using the Seabed AUV to survey fishes in these habitats and provided insights for sample design and enhancements that would optimize the AUV for future operational surveys. [ABSTRACT FROM AUTHOR]

This paper presents a discrete-time adaptive sliding mode controller for an autonomous underwater vehicle (AUV) in the presence of parameter uncertainties and external disturbance. The controller makes the system stable in the presence of system uncertainties and external disturbances. The proposed algorithm has a time varying sliding surface which is obtained by parameter estimation method. The presented algorithms have been applied to the problem of depth control of an AUV. Resulting performances have been tested by simulation. [ABSTRACT FROM AUTHOR]

It is dangerous for Autonomous UnderwaterVehicle (AUV) to work in the deep sea. so varies of risk may be faced by an AUV when working in such environment. Thus, it costs a lot of humanbeing resource to develop an AUV while the data or the collection that attained by the working of an AUV in the deep sea is valuable. Especially for an AUV which carries person, the safety of itself is much more important. This Paper introduces an AUV underwater robot system based on MSP430 microcontroller. The technology of miniaturization, low power consumption, airproof and reliability are given in detailed. It will be disastrous if the AUV is lost in the sea and, at the mean time, an expense of oceanic research and development. So it is extremely significant to explore the self-rescue system for AUV. [ABSTRACT FROM AUTHOR]