Technology Projects > Ocean Electronics > Activities


Ocean Electronics group is working on the development of new Ocean observation technologies like Deep sea autonomous underwater profilers (DAUPD) rated for the depth of 5000m, Drifting buoys (Pradyu) with INSAT communication, C profilers and development of technologies for open sea fish cage culture systems.

I. Open sea fish cage culture technologies

  • Development & demonstration of sphere type submerged open sea fish cage system.
  • Development & Demonstration of water ejector based automatic feeder for submerged fish cage culture system.


  • NIOT’s Marine Bio Technology group breeds fish in floating type Open sea cages systems.  During bad weather condition, the cages are required to be submerged to 10-15m to reduce the damages due to high waves and current. These cages are generally moored in sea at 10-15 m water depth. However the new trend is deploying submerged rigid type fish cages and its feeder for the open sea cages culture. Spar rigid type Submerged cage have been designed with feeder and deployed at Andaman Island for the performance evaluation. As suggested by the recent scientific advisory committee (SAC), 5m diameter sphere (Globe) rigid type submersible fish cage is designed and the detailed engineering drawing has been prepared. The design review and analysis is in progress and the outcome of analysis will be incorporated and fabrication will be taken up. The automatic fish feeder mechanism enhances the submerged open fish cage systems and also will reduce or avoid the frequent visits fisherman to the field.


  • The Spar Rigid type submerged cage is deployed in North Bay of Andaman Island for its life Endurance test and to check the reliability of the system design and found that its performance is satisfactory.  As suggested by the SAC, design and development of Sphere (Globe) Rigid type Submersible fish cage was designed with 5m diameter and its detailed engineering  is completed .Now the tendering for fabrication, Assembly and integration is to be initiated after incorporating ANSYS/ ORCAFLEX outputs into the design. Structural Analysis of the system is under progress.

From view of spherical fish cage culture

  • An Indigenous development of water ejector based feeder for submerged cages was designed, Lab tested for vacuum & controlling parameter and deployed at Andaman Island.

Floating fish cage with automatic feeder

  • Buoy feeder for the existing circular floating fish cage is designed & fabricated with automatic feeding system as per the pre-defined user timing for 2-3 days to reduce  manual operation and same is planned to demonstrate during the March 2019. Under water video acquisition system has been designed and developed and laboratory tested. It is planned to carry out field test at CIBA facility at Muttukadu during March 2019.


II. Deep-Sea Autonomous Underwater Profiling Drifter (DAUPD)

  • Development of Deep Sea Autonomous Underwater Profiling Drifter (D-AUPD) for deep ocean exploration up to 5000m depth has been initiated by Ocean Electronics (OE) group. The Variable Buoyancy Engine of the DAUPD works on the principle of non-rotary marine propulsion system. Design and fabrication of proto type system for 500 m depth has been completed successfully.

Assembly of 2nd DAUPD system

The first proto type unit has been tested extensively for the cyclic test procedures like Mission cycle with simulated sea water column, Functionality test of the entire payloads, Pressure test in hyperbaric chamber till 600 d Bar, Application software cyclic test and Initial test trials carried out in AFT tank and UARF, NPOL test facility at Idukki dam.

  • The 2nd DAUPD float was dismantled and changed the existing Alkaline battery with Lithium Ion battery pack. All the assembled sub-components were tested as an individual and as an integrated system. The control valve zero leakage tests was carried out in the hyperbaric chamber at rate operating depth 500 m (@50 bar pressure). Also the float mission cycle test was carried out with simulated water column in the hyperbaric chamber and observed the system performance at different sequence of operation.


III. Development of Drifting Buoys with INSAT Communication

  • Development of drifting buoy with INSAT communication has been successfully realized by NIOT. The present drifter available in the market use ARGO satellites for communication, which can give 4-6 passes per day. Using Indian geo stationary satellites the drifters provide 24 data sets/day. The Drifting buoy technology has been transferred to two Indian industries and technology licensing agreement (TLA) has been signed with them under NRDC for commercialization purposes. Improvisation and performance assessment of trial produced drifting buoys is being carried out.  Coordination  with National Institute of Oceanography (NIO) and Indian National Centre for Ocean Informatics Services (INCOIS) to effectively utilize our indigenized drifting buoy for their Ocean observation experiments / applications is underway.
  • Development of miniature accelerometer based wave buoy has been completed and short period field deployments carried out. Comparison and validation is being under taken with other similar devices.
  • Periodical review conducted for the collaborative joint project on the development of “A capacitive coupled non-contact type conductivity measurement system” with IIT, Madras.


  • Design and development of laboratory proto model has been completed and tested for lower and higher range of salinity. Fabrication of electronics and housing is in progress for field workable unit. Process of identifying a suitable industry to work parallel with IITM initiated.

IV. ‘C’–profiler

  • This developmental work will aid in collecting near real-time in-situ CTD profile using a tow fish operated from a moving ship/boat in an economical way. Project is envisaged to have a tow fish with conductivity, temperature and depth (CTD) sensors as payload collecting shallow water data which is vital for ocean related predictions. The advantages of the profiler include possibility of real-time onboard data retrieval while the vessel on the move without lifting the probe to deck and swift change of sensor heads on deck enabling observation of various ocean parameters without extra profiler.
  • Field test of the in-house developed Tow fish has been carried out and performance found to be satisfactory. Procurement of winch completed and it is delivered at NIOT and ready for sea trial.


Tow fish sea trial,Load Graph of Tow Fish

Winch at NIOT

    • Firmware developed to acquire and process the data sets of GPS and CTD sensor and also it can create a data file for each profile which contains GPS and CTD data. Simultaneously it also creates one more data file where all CTD profiles are saved and real time plot generated using GNUPLOT software. Preliminary test conducted at ATF tank. Presently CTD sensor cable pays out and winch control software development is in progress.