Monitoring System Based On Virtual Instrument Technology Greenhouse Environment

The whole of greenhouse environment monitoring and controlling technology of China is in a backward level, therefore, it's much needed to research intelligent monitoring and controlling system technology for greenhouse environment in-depth. Virtual instrument technology is the product of technological revolution of new monitoring and controlling technology, its superiority is unable to be achieved by the traditional instrument technology. It is becoming more and more important to introduce virtual instrument technology into the greenhouse field of China.Based on a systematic research in greenhouse environment monitoring and controlling technology of domestic and international, this article combines the development situation of China, especially direct to the climate environment in which the greenhouse of Kunming city, Yunnan province exist, uses the LabVIEW virtual instrument technology platform, designs and develops a set of greenhouse ecological environment monitoring system, which enables to achieve accurate and real-time monitoring for greenhouse environment. This system has advantages such as friendly interface, good accuracy, low cost, expandability and ease of use, etc. It provides a reference for achieving to use virtual instrument technology to monitor and control greenhouse environment. The main content and features of this thesis are as follows:(1) This thesis overviews the conditions of greenhouse environment monitoring and controlling, discusses virtual instrument technology and its application in agricultural engineering status and studying progress, clarifies the superiority of the application of virtual instrument technology in greenhouse environment monitoring and controlling and contrast pointed out the problems of the traditional greenhouse environment monitoring and controlling, and then identifies the whole design program of the greenhouse environment monitoring system based on virtual instrument technology. (2) Based on the analysis of key technology relating with system realization and combining the changing range of greenhouse environmental factors (temperature, humidity, light intensity and CO2 concentration), this thesis improves the system design program. At the same time, based on the DAQ system constituted by high-performance hardware (data acquisition card and sensor, etc) as well as data transmission method based on PCI bus, this thesis builds a greenhouse environment intelligent monitoring system which is the major feature. (3) This system uses a desktop computer as a working platform, uses NI's graphical programming software Lab VIEW from U.S. to design software part of the whole system, the instrument system can monitor multiple signal of sensors simultaneously in greenhouse which improves the measurement accuracy and speed greatly and achieves the real-time collection and acquisition of environmental parameters in greenhouse as well as information management and processing goals. It can analyze directly, save the data to a specified location of hard drive in order to achieve post-processing and playback of view and improve the versatility of whole system. Using ActiveX, system can call Access database through embedded database access interface, provides conditions for the analysis and archives of high-capacity data in the future, and also designs methods of the interface for LabVIEW system calling MATLAB. (4) Propose an idea that using fuzzy RBF neural network predictive controlling combining with the virtual instrument technology and applies them into greenhouse environment controlling. (5) Debugging and improving the system's hardware and software so as to ensure its reliability. (6) In order to test system's stability and accuracy of monitoring data, this thesis tests the system through experiment and compares the traditional test instruments and the virtual instrument system for measurement data. And also make analysis of the data. Experimental results show that:this virtual instrument system is reliable, has high precision, and it can achieve real-time monitoring of greenhouse environment, and it is able to provide some references for China's greenhouse environment control and has some practical value.Finally, the thesis sums up the whole paper and points out the inadequacies of the system design and improvement ideas for the future research work, makes some reference suggestions. This work of this thesis is a useful attempt to expand the greenhouse intelligent control technology.