Research On Control And Communication System Of Offshore Marine Instrument Testing Field Equipment

Its design principle determines that the development of marine instruments and equipment is difficult to complete indoor testing.It is necessary to test and validate the technical performance index of this kind of instrument or system by combining indoor test with marine field test.At present,there are few test sites in China,mainly located near Weihai,Qingdao and Zhuhai.Their sea conditions are relatively good,which can not reflect the characteristics of high nutrient,high turbidity and great salinity changes in the offshore waters of the Yangtze Estuary.Therefore,in many cases,they can not meet the test requirements of the equipment.In order to solve this problem,it is of great value to use the existing island reef and station infrastructure in the offshore waters of the Yangtze Estuary to develop special testing equipment and form a maritime testing ground for marine instruments and equipment.To realize the interconnection between multiple stations is the necessary condition for realizing the maritime testing ground.For this reason,this paper aims at the design and development of communication and control system of test equipment.The main research contents and achievements are as follows:?1?In view of the development status of marine instrument and equipment testing in domestic and foreign maritime testing ground as well as the characteristics of rich nutrients,high possibility of biological attachment,gradient distribution of sediment and salinity in the East China Sea,in order to form a more perfect testing ground,this paper comprehensively investigates and analyses the relevant reefs and testing stations in the East China Sea from the aspects of microwave communication requirement,topographic features,distance,sea condition,nutrient distribution,salinity and turbidity.?2?According to the test requirements of the marine instrument testing ground and the investigation of the offshore stations in Shanghai,this paper chooses the marine characteristics of Hangzhou Bay and Yangtze River estuary,which can reflect the offshore waters of Shanghai,to real-time observe the anti-biological adhesion and anti-corrosion performance of testing instruments and equipment in the maritime testing ground.According to the location,distance,elevation and other factors of each station in the testing ground and the demand of video communication,it establishes a scheme that takes Dahaoshan as the center,Luchaogang,Jiuduansha,Nancaodong and Tangnaoshandao?Xiaoyangshan?as the four stations to send the collected data to Dahaoshan Station for relay,and then data transmission and landing by Dahaoshan Station.After design and calculation,it chooses suitable microwave communication frequency bands for different stations and checks them.In mobile testing,the system bandwidth is more than 2.0 Mbps and the acceptance sensitivity is-83.8 dBm.Within three months,there is no packet loss in the micro-communication system,and the bit error rate is less than 10^-9.?3?According to the differences of different reefs and test stations,this paper presents the basic structure of two sets of devices,i.e.automatic test of fixed ocean instruments and automatic test of floating ocean instruments.It studies remote video control monitoring,sensor lifting mechanism and bidirectional transmission of control signals.It designs a high reliable control card system,which takes STM32F427 as the core of control system,combines many solid-state relay circuits,camera module,motor driver module and data communication conversion module,carries multiple sensors such as dissolved oxygen/temperature,PH,AP-2000 multiple parameter,GPS sensors,and can adapt to salt fog environment.Then,combined with IIS service deployed on Alibaba Cloud and real-time observation of the anti-biological adhesion and anti-corrosion performance of instruments and equipment,it achieves the video and data return of sensors tested on buoys?or fixed detection devices?,and remote control of the system is realized by terminal devices such as computers and mobile phones through access to servers.?4?The field test is carried out according to the requirements of the control system of the equipment.In the multi-site marine instrument and equipment testing ground,it chooses Dahaoshan buoy test platform as an example for data analysis and calculation.After the test platform is put into operation,it tests and analyses various indicators of the system according to the specific use and corrects the parameters with larger errors accordingly.It mainly includes the analysis of power consumption of the buoy system,the analysis of sensor fouling biological attachment and the analysis of sensor data.The test results show that the floating elevation detection device of marine instruments can adapt to the sea conditions in different sea areas,the sea condition observation camera can work normally,the growth of attachments and the operation of lifting device are stable,and each subsystems are running well.The voltage of the floating equipment is maintained at 13.20V and the working current is maintained at 0.36A.The power supply system can work normally for 125.5-141.2 hours in continuous rainy and rainy weather.According to the equipment data upload situation at each site of the testing ground,it collects data and forms relevant curves and reports.?5?It synchronizes the data uploaded to ECS to RDS regularly,and then uses Visual Studio 2017 to develop VSTO visually for Excel.Combined with EXCEL,the data of sensors in the testing ground are processed,analyzed and saved.It carries out data processing,analysis and comparison in the later period according to the test equipment actually carried by the automatic test of fixed ocean instruments and automatic test of floating ocean instruments,and combined with"Maritime Test Standard for Multi-site Marine Instruments and Equipment?Draft?".It carries out a long-term and intermittent data analysis and comparison between the DPS600 PH single parameter,DOS300temperature/dissolved oxygen two parameters and AP-2000 multi-parameter water quality sensor mounted on the automatic test equipment of floating ocean instruments from October 2017 to August 2018.Data analysis and comparison results have good practical application value.They can not only provide accurate data for testing equipment,but also provide data support for later development and testing of equipment.