Wireless Automation Systems: Smart Farming Using Zigbee

Automation is a main area where IoT will play a key role in the near future. Automation has transformed operations in many areas, including agriculture. Today, companies are developing prototypes for farm and greenhouse automation. Let us look at how automation is done using IoT based smart farming solutions.


In a smart farming environment, these are parameters that are usually measured:

  1. Soil moisture
  2. Soil pH
  3. Temperature in greenhouse
  4. Humidity in greenhouse

 Arduino and appropriate sensors can measure the above parameters.

DHT22 sensor for temperature and humidity; PH Meter to measure soil pH, SEN-13322 RoHS to measure soil moisture. 


What next? In a large farm, multiple sensor are deployed across the farm and each sensor data should reach a central coordinator/gateway. A Zigbee/Xbee mesh network  is used to send all the sensor data from all sensor nodes to a main coordinator/gateway system. Zigbee is a wireless protocol developed for low cost  low power wireless m2m network. Zigbee protocol supports point to point and point to multipoint communication, which allows the creation of mesh networks. Zigbee mesh can hold around  65000 nodes in a network.


Now, that the gateway has all the sensed data, an automation logic needs to be developed. Based on setpoints for each of the measured parameters, the system shall be able to trigger the irrigation system.

Valves control irrigation. There are solenoid valves and latch type valves. Solenoid valves, turn ON, on supply of voltage and turns OFF when there is no supply. Other valves available are latch type valves. These valves  turn ON, when voltage is supplied but the interesting thing about these valves is, to close these, you should supply voltage again.

For controlling the irrigation, the system needs to sense the quantity of water irrigated. Engineers  interface flow sensors with Arduino or any other microcontroller. Users, with the help of flow sensors can calculate the amount of water used for irrigation,and this information will also be control the irrigation level, based on this information. The flow sensors work on the phenomenon called Hall Effect. There are some valves coming with valve plus flow sensor combo package.  


There is a need for a IoT driven user dashboard to remotely control operations.  LAMP, GSM, WIFI, etc is used to develop these dashboards quickly. Today we have apps that can help visualize, sensor data and control an IoT system.