Development Of Low-cost Greenhouses Intelligent Controller Based On Embedded System

Agricultural development in our country is in the transformation and upgradingperiod. It is also a period of deepening the reform. The facility agriculture is theimportant content of agricultural information technology and intellectualization. Andit has an important significance to develop the agriculture infrastructure. That willliberate the workforce and increase the income. Facility agriculture also plays animportant role in promoting energy conservation.Base on development status of domestic and foreign facility agriculture, a lowcost greenhouse intelligent controller had been designed which is based on embeddedsystem and wireless sensor network.First of all, the paper analysis the requirements of greenhouses control, anddesign a control system which is based on embedded system structure. The systemcontains the front end which uses the CC2430chip wireless sensor node, measuringthe temperature and humidity of the greenhouse. And then the system through theZigbee wireless transmission network transmits the data to the SINK node, which isthrough a serial port communication with the central controller named TQ2440development board. The embedded Linux system is used in the greenhouse controlsystem, which is convenient for the control system application development. Thetarget of the design of the embedded control system is to control the greenhouseenvironment accurately.Secondly, the article chooses the strategy of the greenhouse control system. Thegreenhouse has slowly time-varying, nonlinear and uncertain characteristics. At thesame time due to the limitation of the traditional PID control, this paper studies thegreenhouse intelligent control strategy, and use direct adaptive fuzzy control methodto control the temperature of the greenhouses, realizing the precise control ofgreenhouse environment.Finally, to complete the embedded software development, the design uses Qtinterface development tools, and complete the function of each part, realize thewireless data acquisition, storage and processing, simple and intuitive interface, which is easy to farmers. On the control strategy of the validation, completed a part of thecode programming, the effectiveness of the proposed control strategy is to useMATLAB software to complete the simulation of the control system of greenhouses.when changing the environmental parameters, or under the condition of objectproperties change, the controller of maximum overshoot, rise time and adjust time andsteady-state error, have very good control effect. The paper verifies that based on thefuzzy adaptive control of greenhouse environment parameters of the controller iseffective. This paper laid a theoretical basis for the further engineeringimplementation of the embedded system.