Agricultural Facilities Intelligent Control System-tomato Production Control

Facility agriculture is through automation control, to create the most suitable environmental conditions for crop growth in order to achieve productive and efficient for the purpose of modern agricultural production. Because the greenhouse is a complex and dynamic environment system, it is difficult to set up mathematical model to control using the traditional way of PID. For the fuzzy control algorithm, equation of state objects is not required, which is also suitable for controlling the nonlinear, time-varying delay system. Therefore, fuzzy control algorithm is adopted to control greenhouse, and for example in summer Greenhouse control, by fuzzy control algorithm to achieve effective and reasonable control of the ambient temperature.(1) By analyzing the effects of major environmental factors on the growth of crops, the tomatoes grown in different periods required is summed up for the optimum temperature, humidity, light intensity and CO2 concentration and other environmental status.(2) Greenhouse makes use of look-up table algorithm in fuzzy control strategy, temperature error as the fuzzy controller input, and sunroof, shade net, fans and wet curtain, etc., as the system’s output. Greenhouse system selects triangle membership function, and in accordance with the relevant rules of fuzzy control design.(3) Greenhouse structure is using the up and down PC control mode, PC control interface with VB programming, which has the function of data storage, real-time data display, transmission control parameters and other functions. The lower PC complete testing and control the greenhouse temperature, humidity, CO2 concentration and soil moisture and other parameters.(4) Sensor layout and selection is completed in greenhouse, and the sensor output current-voltage conversion circuit of the interface design also. The correspondence is studied between the operating rules and the sensor actuator in the greenhouse.Through practice shows that greenhouse system has been better control effect, based on lower and upper PC in greenhouse control system, the MCU technology, serial communication technology and integrated use of sensing technology.