Design and performance of a low power moored data buoy system

A minor change in any one of the ocean parameters, results in a major climatic variation over large areas of Earth. National Institute of Ocean Technology (NIOT) as technical arm of MoES established National Data Buoy Programme (NDBP) in 1997. A solar powered 2.2m discus type data buoy was indigenously developed at NIOT under this programme in 2004. The data buoys were instrumented to measure various metrological and oceanographic parameters. To improve the reliability of the data buoys, NIOT has indigenously developed a low power, moored, data buoy system that works on Lithium Thionyle Chloride primary battery. A low power embedded system is designed with Atmega32 micro controller in master mode and Cool runner CPLD in slave mode for data acquisition & transmission. This system can interface sixteen digital sensors and eight analog sensors. The raw data is stored in a flash memory and averaged data is transmitted in realtime to data reception centre at NIOT Chennai by satellite telemetry. In this paper we describe, a novel, indigenously developed, low power data buoy system powered only by internal battery pack. Extensive laboratory tests have been conducted with the system and field test results are presented.