The Design Of Temperature And Humidity Monitoring System For Large Granary Based On STM32

In order to reduce the loss of grain in the storage process and ensure the quantity and quality of the grain,it is necessary to grasp the temperature data of the grain and the temperature and humidity data of the air in the grain storage process,and analyze and summarize the changing rules and,if necessary,Effective measures to intervene to achieve scientific storage of grain.The traditional means of manual monitoring cannot meet the requirements of real-time and comprehensive,and the current part of the food monitoring system used by the communication method is quite backward,and do not have the system self-diagnosis and recovery capabilities,therefore,design a system with self-diagnostic function and the better communication performance of the granary monitoring system,both to effectively guarantee the quality of grain storage,but also to a large extent reduce the strength of the management staff,with significant social and economic value and practical significance.In this paper,the overall program of the system was designed,the data transmission between the nodes inside and outside the warehouse,using a stable and reliable transmission distance and communication distance CAN bus communication and ARM Cortex-M3 core based STM32F1 series of microcontrollers,Five kinds of functional nodes are designed for the system: Temperature acquisition node use DS18B20 sensor to collect the temperature in the grain,Temperature and humidity acquisition node use AM2302 sensor is to collect the temperature and humidity in the air,the control device node of the cooling and dehumidification,the man-machine interaction node showing the parameter status in the warehouse and the CAN relay node is used for forwarding the data.The working process of the system is that the sensor on the node of the warehouse collects the temperature and humidity data and then transmits it to the human-computer interaction node.The alarm threshold is set on the man-machine interaction node.When the temperature and humidity exceed the threshold,the administrator is reminded to automatically or manually control the equipment inside the warehouse,such as open the fan cooling and drying.The system has state self-diagnosis function,can monitor the status of each node in real time,can diagnose the DS18B20,in the event of failure,you can quickly locate and replace.This paper first designed the overall program of the system,then designed the hardware circuit and software program,and finally the system was debugged.The results show that the temperature and humidity monitoring system has the advantages of accurate measurement,stable communication,self-diagnosis and self-diagnosis,and has the characteristics of reliable reliability,comprehensive function and good human-computer interaction experience.It can be used to promote the grain quality.