Day by day, wireless system demand is increasing in homes due to easy placement and its cost and also you can connect easily by phone or computer. The home automation project is used to control the home appliances wirelessly by using Zigbee wireless communication or computer. Home appliances includes fan, air conditioner and refrigerator, etc. by sending commands through the serial communication from the computer. This project is also very useful to control the electrical appliances in the room.
Zigbee Wireless Technology
There are a number of wireless technologies are used in home automation system like Bluetooth, GPRS and Zigbee technology, etc. This project uses a Zigbee technology, which is used for low distance communication. This wireless technology is developed with low power, low cost and wireless M2m network, which is based on standard IEEE 802.15.4 and functions in unlicensed band 915 MHz, 868MHz, and 2.4 GHz.
This wireless device can communicate at a minimum speed of 250kbps at the 2.4 GHz frequency range. Data rate of Zigbee module is 20kbps at 868MHz & 40kbps at 915MHz. This device can communicate up to a distance of 50 meters in a typical environment and when the environment is ideal then the distance is max. It gives high data output in all low duty cycle applications. Due to this reason, it is ideal for home automation, business and industrial automation where control devices and sensors are used.
Zigbee devices are classified into three types such as: ZC (Zigbee Coordinator), ZR(Zigbee Router) and ZED (Zigbee End Device)
Zigbee Coordinator (ZC): ZC is the root of network tree and bridge to the other network. In each network there is one Zigbee coordinator, which initiate the n/w originally. It stores the information of the network.
Zigbee Router (ZR): It works as a middle router, it takes the data from one router and passes it to another router..
Zigbee End Device (ZED): it has less functionality as compare to ZR and ZC. The function of the Zigbee end device is, it communicates with the parent node. It cannot route data, but the node lets to sleep for a significant amount of time while it is not transmitting. So it gives long life battery and it needs less amount of memory than ZC and ZR.
Zigbee Home Automation
Zigbee Home automation is used to control the home appliances. This automation is used for many reasons of security, ease and energy efficiency. In this era construction of homes and industries includes the wiring for home appliances like telephones, electrical power, TV outlet, door lock and door bell. There are many home appliances are designed to reduce the manpower for instance, washing machine which is used to reduce the manpower for washing the clothes and the water heaters for bathing also reduces the manpower.
Day by day number of appliances are increasing and interconnection of device and communication between them is very important. For example, the air conditioner will send a command to the owner’s phone when it needs for clearing.
The embedded system is working as a virtual intelligent system when someone enters into the door it will send commands to the microcontroller. If the alarm is set and no one is in the home, then the system could call to the owner
Zigbee Home Automation Project with Explanation
This project is used to control the home appliances using your Zigbee and PC. All home appliances are connected with the microcontroller. When the command is sent over hyper terminal software. This project includes two main parts, such as transmitter and receiver. The transmitter section comprises of Zigbee transmitter & RS232 circuit and receiver comprises of Zigbee receiver & ATMEGA128 which is connected to relay and different home appliances like fan, motor, bulb, etc.When the command is sent through the PC hyper terminal. The command is transmitted through Zigbee transmitter, then the Zigbee receiver receives the command. After receiving this command it decodes and sends to the ATMEGA128 microcontroller. The micro-controller responds according to the command.
For instance, if we send command 1 to microcontroller, then the fan will ON and if we send command 2 to the microcontroller, then the motor will ON. If we send wrong command to microcontroller then the red LED will glow on the board. All the AC devices are connected through relays when the microcontroller transmit command 1 to relay the matching device is ON and when transmit command 0 to relay then the device is OFF.
The Hyper terminal software runs on windows platform and it controls the remote device by sending text based command. It is used for the local serial interface for communication or n/w. In this project, by sending „A‟ the fan is on and by sending „a‟ the fan is off. The bulb is on & off through command „B‟ and „b‟ likewise by sending command „C‟ and „c‟ AC is turned on and off. To turn on and off the gate lock we have to send commands „D‟ and „d‟.
Applications of Zigbee Home Automation
The applications of Zigbee technology mainly involve in where we require low cost, low data rate, reliability, security and low power consumption Zigbee is used in different fields like industrial automation, medical, home automation etc.
- It is used in Vital Monitoring for Heart-rate Monitoring, Body heat Monitoring and Personal equipment control
- It is used in Consumer Electronics like Remote control, PC- peripheral, Dimmer/ switches and electronic kits
- It is used in alarm and security systems like Smoke detector and Water leakage alarm
Advantage of Zigbee Home Automation
The advantages of home automation system using Zigbee are
- It consumes less power and less time.
- Zigbee home automation is comfortable and very safe.
- The range of Zigbee is approximate 100-300 feet.
- The limitation of the Zigbee home automation is If there any damage due to the breaking of the cable the whole system get damaged
- In very rare cases, the reliability of home automated device is decreased
This is all about Zigbee Home Automation and in this project Zigbee is used for wireless transmission and command is sent from hyper terminal of PC. In future, this project can be enhanced by replacing a remote Zigbee in the place of Zigbee. Furthermore, any doubts regarding this topic, please give your feedback by commenting in the comment section below. Refer Free E-book on communication systems. Here is a question for you. What is the range of Zigbee?