摘  要随着现代农业不断向着机械化和智能化方向发展，温室作为农业现代化设施的一个重要方面，在农业的现代化发展中具有极其重要的作用。另外，滴灌作为目前农业灌溉最节水的灌溉技术之一，在世界各地的生产中得到了广泛应用。将温室和滴灌技术相结合，不仅对温室节水灌溉智能化程度的提高有所帮助，而且对作物的生长发育、产量的增长和品质的提高都有很大的裨益。

此课题设计了一种智能滴灌控制系统。整个系统的控制核心选用的是单片机，另外，选取蒙蒂思方程作为计算模型，以此为基准计算灌溉量。通过传感器和光敏电阻测得温室内部的温度值、湿度值以及光敏电阻值，随后求得净辐射值。以这些参数作为决策模型的计算变量，经过单片机预设程序的处理计算，即可获得一段时间内温室内生长作物的蒸发蒸腾量，从而使得设定的滴灌时间与作物的生长情况相适宜。利用串口通信向上位机发送先前采集的温室环境参数和计算求得的蒸发蒸腾量。通过仿真可以看出，这种方式简便有效，温室作物的灌溉较准确，值得运用。

本课题设计的智能滴灌控制系统的对象为黄瓜，在黄瓜的整个生长过程中，仅需改变其各个生长阶段对应的作物系数KC即可满足黄瓜正常生长的需水量。本系统应用范围较广，可以适用于大量农作物，只需在上位机界面修改该农作物生长各个阶段的作物系数即可。农作物的作物系数可以通过查询联合国粮农组织FAO推荐的作物系数表得到。59218

毕业论文关键词：温室；智能滴灌；单片机；蒙蒂思方程

 Abstract

With the development of modern agriculture gradually moving to mechanize and intelligent, greenhouse as an important aspect of the modern agricultural facilities, has an extremely important role in the development of modern agriculture. In addition, drip irrigation, as one of the most water-saving irrigation technology for agricultural irrigation in this world, has been widely used in production. Greenhouse and drip irrigation technology combined to applying in modern agricultural production, are not only helpful to improve the intelligent degree of greenhouse water-saving irrigation, but also benefit to crop growing and improve production increasing and quality improving. 

This topic designed an intelligent drip irrigation control system, which choosing a single-chip microcomputer as its core controller, choosing Penman-Monteith equation as its calculation model. Based on these, the system calculates the amount of irrigation. The system uses temperature, humidity and light-sensitive resistance value which can be measured by the sensor inside the greenhouse to obtain net radiation values. Taking these parameters as the calculate variable of the decision model, single-chip microcomputer uses program to calculate the crop evapotranspiration within a period of time, in order to set the appropriate duration of irrigation which suits crop growing. Environment parameters inside the greenhouse and calculated crop evapotranspiration are sent to the host computer. Simulation results show that the method is reliable, effective and convenient, and the system can be used for accurate irrigation of greenhouses.

The intelligent drip irrigation control system was designed for cucumber. Through the whole growing process of cucumber, we only have to change its crop coefficient KC in different stages of its growth that can meet the water demand for normal growth of cucumber. The system has a wide range of applications, which can be applied to a large number of crops. The work we need to do is to change crop coefficients in the PC interface. The crop coefficient can be obtained by querying the crop coefficient table recommended by FAO.

Keywords: Intelligent drip irrigation; Single-chip microcomputer; Greenhouse; Penman-Monteith equation