NATIONAL INSTITUTE OF OCEAN TECHNOLOGY Velachery, Chennai, Tamil Nadu

Wind speed and direction are measured using a fast response low threshold anemometer and a counter balanced wind-vane from Lambrecht instruments.

Range : 0 to 35 m/s

Marine Sensor Systems group was established in September 2005 to cater the mandate of NIOT to develop and demonstrate technologies for oceans. Since then group has been concentrated in the development of different type of underwater sensor systems apart from electronic support given to the other groups in NIOT. Marine sensors are used in a wide variety of applications. Most of the underwater systems are acoustic based systems with underwater electronics. Presently, the group has the capability to design any type of sensors for underwater applications and the group activities have been attracted several public sector industries.The design, development and integration of electronic systems for underwater applications pose many insurmountable problems. Needs of NIOT are unique and all the requirements could not be met with the facilities available at NIOT earlier. Now, facilities to qualify electronics under different conditions of underwater operation have been established like, EMIEMC analyzer, Helium Leak detector, Environment testing systems.

Hyperbaric test facility is used to simulate the pressure in deep sea environment inside a high pressure vessel. The facility has been designed to test components with external pressure up to 90 MPa (900 bar) max., which is approximately equal to 9000 meter of water depth.This facility is the first of its kind in India. Testing in this facility can save lot of time and money for qualifying underwater components. Which otherwise would have been by actual testing in the sea at that depth.

Thickness : 150 mm

NIOT is using various hydraulic systems like high pressure proportional control valves and high pressure Sub-sea hydraulic pumps. These systems must be qualified and tested for its Sub-sea operating conditions. The test rig is also used for calibration and determining the pressureflow characteristics.

Hyperbaric test facility is used to simulate the pressure in Deep-sea environment inside a high pressure vessel. The facility has been designed to test components with external pressure up to 90 MPa (900 bar) max., which is approximately equal to 9000m water depth. This facility is the first of its kind in India. Testing in this facility can save lot of time and money for qualifying underwater components, which otherwise would have been by actual testing in the sea at that depth.

A Low cost portable echo sounder integrated with a GPS and a telemetry system was designed, developed and tested up to 80 m water depth off-chennai with endogenously made transducer.GPS interface and RF telemetry were provided in the echo sounder to enable the user to note the position of the vessel and water depth at any location in the boat and is given in above figure. The remote hand held display for the echo sounder makes it convenient for the fishing trawlers and small boats to see the depth and location of the boat during their voyage.Very few electronic components are directly exposed to the hydrostatic pressure exerted by the water column above them. Most of the components and PCBs are housed in either in pressure casing, which can withstand the pressure or in a pressure compensated chamber.

The buoys are equipped with global positioning system, beacon light & satellite transceiver.Lithium battery pack is used for supplying power to the entire buoy system.Few buoys are designed to carry additional sensors to measure water quality parameters and subsurface temperature.

Air pressure is measured by using Vaisala digital barometer. The pressure is measured based on silicon capacitive type transducer.