Design And Reseach Of Deepwater Robot Dedicated Heat Flow Probes

The area of ocean occupied about71%of Earth surface area, which contains precious and abundant resources. In recent year, ocean resource, especially deep-ocean resource has acquired rapidly exploration. Therein, Nature Gas Hydrate (NGH) is an new energy resource discovered by the scientist, which is also called the "Combustible Ice". The ingredient of NGH is closed to the Nature Gas (NG), but much purer. In the north of South Sea of China, there contains abundant NGH resource, hence it is an urgent affairs to develop advanced high-precision equipment to explore this clear resource.The stable zone of NGH is influenced by seafloor heat flow, seafloor pressure, gas ingredient&salinity of sediment and etc., in which geothermal gradient of sediment is an important measurement of predicting the stable zone of the hydrate. Therefore, it is of great practical significance to explore the data of seafloor heat flow.To obtain the seafloor heat flow data, it is generally to measure the thermal conductivity and the temperature gradient. Using heat flow probe to measure the heat flow of the seafloor sediment is a simple and efficient method. The topic presented in this paper is an important component of the "Research and Development on NGHExploration Technology" project declared by the Guangzhou Marine Geological Survey (GMGS). The purpose of this project is to provide a specified heat flow probe integrated on the deep-ocean robot "Remote Operated Vehicle"(ROV) equipped on China’s first deep-sea exploration vessel’The Marine6" in search of combustible ice to explore the temperature gradient of the seafloor sediment. The probe must be adapted to the low temperature, high pressure and strong corrosiveness environment of the deep-ocean. We call this probe "Needle Fish" because of its needle-like shape."Needle Fish" uses micro CPU ADuC845with ultra-strong A/D conversion function, which processes the data collected by5high-precision thermistors by using "Timeshare sampling principle" and restore the data to the data storage unit AT45DB161. The entire procedure was determined by the clock chip DS13O2monitored by the micro CPU. The communication between the "Needle fish" and the upper machine is using485Bus Communication protocol.The architecture of the "Needle Fish" consists of mechanical shell and inside circuit board; the circuit board consists of hardware circuit and system software; the system software consists of human-machine interactive software of upper machine and lower machine software.During the development of "Needle Fish", many indoor simulation experiments are carried out including "Constant Temperature Trough Test" and "Reaction Speed Test for Heat"."Needle Fish" has equipped on "Marine4","Marine6" and "Jiaolong" research vessel and accomplished many exploration, which has obtain many valuable heat flow data with measurement accuracy of temperature is0.01℃and resolution ratio is0.005℃. Therefore, the probe can be practically used in our deep-ocean heat flow exploration. In this paper, the operating principle of each part, the operation of the "Needle Fish" and the sampling data collected in the field are introduced in detail.