Function and Designing of Automatic Observing System for Agro-meteorology

Based on the proposed technique thought and designing principles, the hardware component parts and software function is designed for automatic observing system of agro-meteorology (named AOSA), which is visual and real time and can be controlled remotely according to the requirement of modern agro-meteorological operation. The AOSA is made of the automatic observing system of crop growing and meteorological observing as well as environment monitoring in the field. It includes temperature and humidity sensors for different heights, and solar radiation, photosynthetically active radiation, infrared temperature, rain, wind sensors above crop, and soil humidity and soil temperature sensors for different depths in soil. It can realize automatic observation of crop growing phases, crop height, crop cover, and main agro-meteorological disasters by means of crop meteorological observing and soil moisture data. There are many observing elements in agro-meteorology observation task, but the urgently needed elements and crop types in operational observation are solved in AOSA.The automatic observing techniques are introduced systematically. The technological specification of crop growing sensor is the foundation of AOSA research and development, which (resolutions of CCD sensors and installing height) have influences on accuracy of the crop automatic distinguishing. The results show that CCD sensor height and focus for short stalked plant is not below 3 m and 16 mm respectively and CCD sensor height and focus for tall stalked plant is not below 5 m and 21 mm respectively to observe an area of 5 m² properly. The automatic distinguishing technique of crop development phases is realized by means of picture differentiating technique, considering crop growing and meteorological index. Crop observation is complicated, so different development phases have different algorithms of automatic observing. Observing method of crop height is developed by photography and dynamic tracking technique. The method of plant cover calculating is given out per hour, and automatic observing of crop density and leaf area will be solved through researching out the relationship between them. The AOSA will preliminarily realize visual, real time and automatic observing of main agro-meteorology observation through image processing and photogrammetry techniques.