Research On Water-saving Irrigation System Controled By MCU

The level of auto-control water-saving irrigation technology reflects the development condition of agriculture modernization .The low automatic level of irrigation system is the main reason that prevented our agriculture's development. As to this condition, this paper mainly studies the drip water-saving irrigation system that controlled by MCU (Micro-controller Unit). This system can supervise and control moisture of different soil. It can irrigate to different farm corps with the right amount of water at the well time. The control part that consists of MCU and PC (personal computer) is its core. Research work hand been carried on to the relationship between soil moisture and water, irrigate control technology, hardware and software program and so on.It adopts the top and bottom form to realize the control function of drip irrigation system. Based on TA89C51 MCU, the bottom hardware system mainly consists of soil moisture sensor, Signal transfer circuit, monitor display circuit, out port control circuit, malfunction display circuit and the procedure programmed with MCS51 assemble language. The top part is chosen to use above PC 586. It realizes to finish voltage conversion through the MAX232 chip and delivers the data in serial communication between a PC and a MCU. VB high-level language is used to build up the friendly man-machine interface on PC. This system mainly has the following functions: people can set the related parameters of soil moisture that farm crops requested on the PC interface. The soil moisture sensor embedded under the ground can check out soil moisture in analogue signal, which can be converted to digital signal by bottom system. The digital quantity will be showed on LED display. At the same time, MCU can deliver this moisture value to PC, through the inside program, PC can compute the amount and time of irrigation, then show them on the interface and feedback this irrigation information to MCU. If need to irrigate, then start the alarm device, sending out irrigation signal, driving amplifying equipment, and opening the electromagnetism valve to carry on a count down timing irrigation. If don't need irrigate, the amount and the time of water showed on PC will be all 0. It doesn't irrigate.In addition, some experiments have been done to study the relationship between the soil moisture and the amount of water. Fuzzy control theories are used to analyzing and processing the soil moisture. Many debug experiments had been done to the MCU system and tested to run well.All the system can collect and process the single factor as well as double channel data. If changed slightly, it can apply to multifactor and multi-channel conditions.This system has many characteristics such as strong flexibility, Operate easily, run reliable, and so on. It will have a vaster development vista.