An environmental control system for a chicken coop

The breeding industry has always been the largest and most mature industry in China. Chicken farm of temperature, humidity, light and air quality has great influence on the growth of the crowd, our country has been to develop in the direction of mechanization of equipments in the cages of chicken, chicken group constitution is more special, susceptible to infectious diseases, farmers in and out of the farms are also associated with the outside world source into cages henhouse, then intelligence brings out the importance of environmental control system.

 

Circuit design of humidity detection module

The main detection object of humidity is the air humidity of chicken coop. This design adopts DHT11 digital temperature and humidity sensor as the detection element of temperature and humidity. Only one of the three pins is the data transfer pin, that is, only one I /O port is occupied. The humidity measurement range of DHT11 is 20% ~ 90%RH, and the measurement accuracy is ± 5.0%RH.

 

Temperature detection module

 

The chicken farm adopts the way of cage raising, the cage is 3-4 layers, each layer is about 45 cm apart. Due to the special form of breeding, the temperature varies greatly due to the different measurement locations. Therefore, it is necessary to place sensors in multiple three-dimensional positions to accurately detect the temperature of the coop and coop. This design USES DS18B20 temperature sensor as the detection element. DS18B20 has three pins, and the temperature range is -55 ~ 125 ℃. More importantly, DS18B20 has a unique single-wire interface that returns temperature measurements to the MCU and address signals at the same time. For the multi-point three-dimensional temperature detection system, the return value MCU can accurately find the temperature detection address.

 

MCU module design

 

The system adopts 89C51 MCU as the controller. 89C51 MCU is the basic product of McS-52 series MCU of INTEL company, with a total of 40 pins, 32 two-way input and output I /O ports, built-in 8-bit central processing unit and 256 bytes internal data storage. Two 16-bit timers/counters and five 2-level interrupt structures. The working voltage is 5.0 V

 

Clock module design

 

This design USES DS1302 chip as clock chip. DS1302 is a low - power real - time clock circuit developed by DALLAS corporation. The structure, working principle and application of DS1302 in real - time display time. It can time year, month, day, week, day, hour, minute and second, and has many functions such as leap year compensation.

 

Relay driver module design

 

In order to improve the reliability of the system, the single-chip microcomputer is used to input high level or low level to control the opening and closing of the equipment. When high electricity is input at the control end of the single-chip microcomputer, the Q7 transistor is conducted, and the diode inside the photocoupler has current flowing through it. The triode on the right side of this time coupler is conducted, and the solid-state relay Km controls the electrical equipment. When the input of low power at the control end of the single-chip microcomputer, the Q7 transistor is disconnected, no current passes through the diode inside the photocoupler, the triode on the right side of this time coupler is disconnected, and the solid-state relay Km control electrical equipment is disconnected. Because drive fan in different environment, air conditioning, incandescent lamp intensity and quantity are different.

 

Display module design

 

After the sensor signal is detected, it is sent to the single-chip microcomputer for processing. At the same time, 12864 pairs of temperature, humidity, smoke, light and other parameters are displayed. 12864 is liquid crystal display, which can display letters, Chinese characters, Numbers and simple graphics, meeting the design requirements of this design.

 

In this study, an intelligent monitoring system was designed for the special growth requirements of chickens. In this system, not only temperature, humidity, light, smoke and other environmental factors were monitored intelligently, but also the chicken ring could be cleaned by timer. By the single-chip microcomputer to fan, air conditioning, incandescent lamp group and other hardware equipment control, so that each environmental factors remain in the appropriate range, so as to ensure the healthy growth of chickens, avoid the traditional breeding blindness and human dependence.