Recognising the imperative need for encouraging indigenous design and development of marine instruments and servicing facilities, the Department of Ocean Development has initiated a programme on design and development of some of the marine instrumentatioris. During the earlier phase development of free-fall recording bathythermograph, current metres, moored ocean data buoys etc. were undertaken.

6.1 Shore to Vessel Communication System

During the year 1991-92 a pilot project for the development of vessel to shore communication system was taken up. Under this project 1000 walkie-talkie sets and 1000 compass sets are to be distributed to marine fishermen and two shore stations each in Andhra Pradesh, Tamil Nadu, Kerala and Karnataka are to established. This project is implemented in association with Marine Communication and Electronics Equipment, Visakhapatnam and the Fisheries Commissioners of the four State Governments. The production of the equipment is expected to be completed by the end of this financial year and all stations are to be commissioned during 1993. The first shore station at Manginapudi near Machilipatnam in Andhra Pradesh was commissioned on 29 January 1993. Forty four walkie-talkie sets were distributed to fishermen operating traditional fishing boats, fibre glass boats and beach landing crafts .

The sets were distributed through five cooperative societies in the area, which were also acquainted with the twin objective of the system, i.e. the voice communication from the fishing vessel to the shore and vice-versa at times of emergency and the communication of Potential Fishing Zone information under MARSIS programme. The project in its second phase would also be extended to other coastal states:

To achieve an accuracy better than 1 mm and to replace the age old conventional tide gauges of Survey of India to measure and monitor the changes of sea level including its mean, an optical shaft encoder 8 cm dia brass screw transducer apd float weight mechanism has been developed by Western Regional Instruments Centre, Bombay under a project funded by the Department. The digital tide gauge is capable of reading the tidal level to an accuracy of 1 mm and with a resolution of 60/120 microns. A built in real time clock controls the power to the digital tide gauge thus optimising the power consumption and extending the battery life. The field trials of this along with other tide gauges are being carried out at Bombay Port Trust.

No fish finding instrument is available at low cost to traditional fishermen to know the depth and location of fish in sea. This equipment is being developed through Electronics Research and Development Corporation, Thiruvananthapuram.

This instrument is intended to scan vertically down for gathering information on location and depth of fish abundance on a video screen. This indigenously developed instrument is rugged and easy to carry in small boats. The first prototype is ready for field trials.

The Department has also taken up the work of creating backup facilities for scientific instruments on sea going vessels owned and operated by various Departments of the Government. This work has been 1 entrusted to the Instrumentation Limited, Kota. A feasibility report on maintenance of scientific instruments for the Department's vessels, viz. ORV Sagar Kanya and FORV Sagar Sampada is expected to be finalised by June 1993.

 Based on the R&D on marine instrumentation completed during 1992-93 a few more instruments such as (i) Micro-processor based instrumentation system for measuring nutrients of sea water, (ii) Micro- processor based instrumentation system for measuring marine pollution parameters, (iii) development of moored buoy for continuous monitoring of sea parameters for the purpose of identifying marine fish, (iv) further R&D work to improve the tide gauges programmes to incorporate the modern technology etc. are proposed to be taken up.

Under a project funded by the department, a few low cost drifting buoys were designed and fabricated by National Institute of Oceanography (NIO), Goa with the aim of collecting sea truth on Sea Surface Temperature (SST) and circulation required for validating the data obtained from remote sensing satellites. Two principal objectives considered in the design were to make a drifter with known water following characteristics staying 'attached' to the water mass, and to make a drifter that will last for many months in the open ocean environment.

The drifting buoy includes a surface float housing the electronics unit, two sensors for SST, ARGOS certified transmitter, batteries. and antenna. The float is made of fibre glass with polyurethane foam. The system is low powered and transmits position and averaged SST data once in 90 secs.

The feasibility study concerning the design and development of a submersible capable of diving to a deptli1 of 600 metres for exploration in the first phase and 2500 metres in the second phase entrusted to Naval Science and Technological Laboratory, Visakhapatnam has been completed. The report is being evaluated for follow up action.