| Greenhouse as an important architectural form of facility agriculture,it can provide a suitable growing environment for crops and play an significant role in the cultivation of out-of-season fruits and vegetables and ensure the supply of fresh fruits and vegetables in winter in northern China.With the strong support of national policy and market demand,China’s greenhouse industry has achieved rapidly development.The agricultural plan issued by Jilin Province in 2019 has made the construction of large-scale,efficient and energy-saving multi-span intelligent greenhouse as the key task.Currently,the facility greenhouses in Jilin Province are still simple solar greenhouses.The greenhouse production has a low degree of automation,relying heavily on labor,weak technology support,lack of stable and practical greenhouse monitoring system,which fails to meet the needs of efficient utilization of greenhouse resources,high-quality and high-yield crops,scientific and convenient use of management.In view of the above problems,combined with the actual situation of greenhouse facilities in Jilin Province,this paper designs a low-cost,low-power,easy-to-operate facility fruit and vegetable monitoring and control system based on the Internet of Things.The system includes three parts: greenhouse site nodes,remote cloud server and user access terminal.Among them,greenhouse site nodes deploy a wireless monitoring network in the facility greenhouse,including the environment monitoring node,the device control node and the aggregation gateway node.The environmental monitoring node realizes real-time collection and uploading of various environmental parameters in the greenhouse to the aggregation gateway node.And the device control node can receive the remote server control command and let the greenhouse roller shutter matching,water pump or other equipment automatic or remote control.The aggregation gateway node can combine with the NB-IoT technology to realize the communication of ZigBee network with remote cloud server,to complete the environmental data uploading and control commands issued in the greenhouse.The remote cloud server implements data storage,analysis and calculation,and intelligent control functions;The user access terminal completes remote greenhouse data viewing and device control of the facility through the Web and the mobile phone APP.In order to ensure the system works efficiently and stably,this paper carries on the contrast test,the software simulation,the field experiment from many aspects of the system monitoring function,ZigBee network quality,equipment control effect.The results show that the system in the greenhouse is stable、reliable and rapid response under a long-term working conditions,and the remote server software is simple to operate.Tests result demonstrated that greenhouse irrigation controlled by the system can keep the soil moisture content at 70.5%,the max control error is 7.5%,which was good for the growth of greenhouse tomatoes during fruiting period.The system can realize rapid upgrade and transformation for the existing solar greenhouse,improving its automation level and meet the requirements of efficient greenhouse and scientific management.It has a certain promotion and application value in actual greenhouse production. |
