摘要通过研究现有的各种灌溉技术，分析比较各自的特点与适用对象，从而选择出适合温室苗床的灌溉技术。利用先进的技术来改变现有的温室灌溉技术。从而达到有效的利用水资源和提高作物产量的目的。本次设计的温室自动灌溉系统经过对土壤湿度的检测，从而控制电磁阀的通断来达到自动灌溉的目的。土壤湿度的检测与控制部分包括了土壤温湿度的检测和自动浇水系统。土壤温湿度的检测以湿度传感器为感应部件，将检测到的土壤温湿度值转换为 将土壤湿度传感器检测到的土壤电阻Rt转换为多谐振荡器的振荡周期，周期增大到预定值时，控制电路启动灌溉。当监频器电路检测到湿度达到要求时，即停止灌溉。通过预先设定浇水的上下限值与土壤湿度值相比较，当低于下限值时，定时器输出一个信号控制电磁阀打开，开始浇水，高于上限值时再由定时器输出一个信号控制电磁阀关闭，停止浇水。本文为温室灌溉进行了初步探索和实验，取得了一些对开发设计新产品有益数有益的数据和经验。7393
关键词：土壤湿度；自动灌溉；定时器
Abstract   By studying the various existing irrigation techniques, analysis and comparison of their own characteristics and intended for greenhouse seedbed irrigation technology. The use of advanced technology to change the existing greenhouse irrigation techniques. So as to achieve efficient use of water resources and improve crop yields purposes. The design of the greenhouse automatic irrigation system after the detection of soil moisture, thereby controlling the solenoid valve off to achieve the purpose of automatic irrigation. Soil moisture detection and control section includes soil temperature and moisture detection and automatic watering system. Soil temperature and moisture detection sensor humidity sensor components, will detect soil temperature and humidity values converted to soil moisture sensor detects soil resistivity Rt multivibrator oscillation cycle, the cycle time is increased to a predetermined value, control circuit to start irrigation. When the monitoring frequency circuit detects the humidity to meet the requirements, that is, to stop irrigation. By pre-set upper and lower limits watering soil moisture values below the lower limit, the timer outputs a signal control solenoid valve open, start watering, higher than the upper limit by the timer output a signal controlling the electromagnetic valve is closed to stop watering. The preliminary exploration and experimentation for greenhouse irrigation, beneficial to the development and design of new products useful data and experience.
Keywords: soil moisture; Automatic irrigation; timer
目录
1  绪论1
  1.1  研究的背景和意义…1
  1.2  温室苗床2
 1.3  国内外自动灌溉控制技术研究现状2
  1.4 课题研究的预期功能…5
2  设计思想与注意要点5
   2.1  设计思想5
  2.2  注意要点6
 3  电路组成及灌溉实行8
3.1  土壤湿度传感器的选择8
 3.2   555定时器9
3.3 555定时器接成多谐振荡器…11
3.4 灌溉实现…12
3.5  继电器16
3.6  电磁阀17
4   实验结果及分析
  4.1土壤湿度与频率的实验参数…18
  4.2  控制结果分析19    
5  工作小结21
   结束语…22
   参考文献23
绪论
  1.1研究的背景和意义
   近年来温室育种得到迅速发展，与此相关的自动灌溉技术在温室育苗的整个过程中发挥着非常重要的作用。它直接影响作物的生长发育以及经济效益。因此有必要对当前的各种灌溉技术进行一定的研究。从而选择一种适合温室苗床的自动灌溉技术。 温室苗床自动灌溉系统设计:http://www.youerw.com/zidonghua/lunwen_5350.html