As we know that Zigbee technology is the most popular standard for home automation and short range wireless personal area networks (WPAN’s), similarly Android is the widespread tablet and smart phone technology. Enabling Zigbee and Android technologies in one platform, we can exploit an efficient control system than using individual technology. Thus, this article is intended to give a brief idea of interfacing Zigbee communication to the Android control application based real time projects.
Zigbee technology is a wireless communication that makes use of XBEE module as RF. According to an RF communication, the basic RF modules operate at 434MHz frequency. Based on this frequency, the possibility to transmit the data in proper synchronization is nil. XBEE modules operate at a frequency of 2.4 GHz, which is more than the basic RF module’s frequency. By using this XBEE module, data can be transmitted for long distance.
Zigbee is a protocol used to operate X-BEE modules. Zigbee protocols are commonly used in commercial buildings, industrial applications, health monitoring, telecommunication and retailing sectors. Zigbee technology is the most prominent radio network in home automation. Zigbee technologies are mesh networks possessing many ways to send messages bound to reach their destination.
Zigbee name discusses mesh networking concept because the message from the transmitter is in zigzag fashion like bees, looking for the best path to the receiver. Zigbee is a compatible product that can be built by any company without paying any license fee for this technology. This is advantageous for Zigbee in the market place.
Zigbee Sensors are available in different versions depending on the actual needs and typical environments. There are a few among such sensors like Zigbee optical smokes sensor, Zigbee magnetic sensor for detecting the status of the windows and doors, Zigbee occupancy light and temperature sensors for detecting movement, temperature and light.
The XBEE RF module is designed to operate within the Zigbee protocol, and it supports unique needs such as low-cost and low-power-wireless-sensor networks. The XBEE module requires minimal power and it provides reliable delivery of data between remote devices.
The X-BEE modules are better to use because they are reliable and self heating, easy to deploy, secure, affordable, and support large number of nodes with a very long battery life. X-BEE modules are mostly used in remote and industrial areas for monitoring physical parameters like temperature, smoke, etc., using the temperature sensor and smoke sensor.
X-BEE module can be used in different areas such as remote control applications, wireless home networking applications, data logging applications, swarm robotics and in wireless audio transmission applications. For a better understanding of this concept, the following practical application based project that uses ZIGBEE technology is quite helpful.
Zigbee Technology Based Project
XBEE Based Remote Monitoring of 3 Parameters on Transformer
This project is designed to acquire the data of transformers remotely by using a XBEE module. This project uses a temperature sensor, a potential transformer and a current transformer for monitoring the data of the transformer, and sending the data to a remote location.
The analog values of temperature, current and voltage of a transformer are converted into digital values through a DC and send these values to the microcontroller and the data is transmitted to the receiver section through the XBEE module which is operating at the frequency of 2.4 Gega Hz.
A power-supply block provides power to this entire transmitter section. The power supply consists of a step-down transformer, which steps downs the voltage to 12V AC voltage, and converts it into a DC by using a bridge rectifier, and it is regulated by a voltage regulator. This regulated DC voltage is used for operating the entire circuit.
The receiver section receives the transmitted data through a XBEE receiver module placed at the receiver section and compares the analog values with the specified limits that are already programmed in the microcontroller.
If temperature, voltage and current values violate the limits, then the microcontroller sends control signals to a relay driver. This relay driver further drives a set of relays that operate different loads. In this system, the loads can be feeders to switch the transformers when a voltage or current exceeds the limits. These parameters will be displayed on the LCD display.
Android is the latest operating system for mobile phones such as smart phones, tablet computers, Google TV and other devices. Android supports wireless communications by using GSM mobile –phone technology, 3G and WI-FI networks. Android is an open source operating system which means it is free and anyone can use it. Android was first developed by HTC in the year 2008 and HTC got collaborated with Google in the year 2010 and subsequently with Samsung and made Nexus.
Nowadays many of the Android smart phones are in the market like HTC, Motorola LG and Samsung. Among these smart phones, Samsung Galaxy note 3 is the best Android cell phone with features like snapdragon800 core processor with 3GB RAM, 1080P display and inventive stylus input options.
Android Technology Based Projects
1. Density Based Auto Traffic Signal Control with Android Based Remote Override
Traffic congestion is a major problem in many areas all over the world; however, the problem can be overcome by using a density-based auto traffic control signal.
This project is designed to develop a density-based traffic signal control system with an Android based remote override. During normal time, the signal timing changes automatically based on the traffic density at each junction; whereas in emergency conditions like during the movement of speeding ambulance and fire brigade it will run on a priority basis by a built-in Android application device remote control for overriding and setting the green signal in the desired location and blocking the other lines by a red signal.
The traffic signal is generally based on a fixed-time concept allocated at every end of the junction which cannot be varied according to the varying traffic density. However, sometimes higher-density zone prefers green signal for longer time compared to the started allocated time.
An android application device is given as an input to the microcontroller through a Bluetooth device which is used during emergency. The override feature is activated by this device and the remote operation can be achieved by using any smart phone or tablet with an Android OS with a GUI. When the density is low at one end, then the priority is given to the higher density zone, and it is indicated by the green signal. Similarly, the process can be done in other directions by remote operations.
The density is detected by placing three IR sensors in each way as low, medium and high-density sections in meters of length from the actual signal. When the vehicles present up to high-density medium, then these IR sensors send the signals to the microcontroller. The microcontroller then takes action by glowing a green LED for that way.
2. Metal Detector Robotic Vehicle Operated by Android Application
The project is designed to develop a robotic vehicle detecting the metals on its path which is similar to sensing land mines. The robot is controlled by a remote android application. Remote operation can be achieved by smart phone or tablet with Android OS on Graphical User Interface based touch screen operation.
A metal detector circuit is placed in the transmitter end that gives the information about the suspecting the landmines ahead. An 8051 microcontroller is used to perform the desired operation.
In the transmitting end android application device is used for sending commands to the receiver, to control the movement of the robot like forward, backward, left and right etc. Motors are placed at the receiver end for the movement of the robotic vehicle and motor driver is used to perform the actions to move the vehicle in forward, backward, left and right directions. The entire circuit related to vehicle movement is powered by the 6V battery while 9V battery is also provided to supply the power to metal detection circuit.
A metal detector circuit mounted on the robot body and its operation can be carried out automatically on sensing the metal underneath. As soon as robot senses the metal it generates an alarm sound with buzzer attached to it. This metal detector circuit uses inductance coil which detects the metal near to it by changing its resonance properties. By this way android technology is useful to operate the remote robot with use of Bluetooth modem attached with vehicle.
Until now we have discussed about the Zigbee and Android technology and their practical projects. Henceforth let us discuss the project that combines these two technologies so that you can acquire more knowledge about using these two for implementing projects.
Green House Automation Using Zigbee and Android Smart Phone
This project is designed for wireless monitoring and controlling the parameters of a home by using Zigbee. Nowadays home automation is a trending technology that uses mobile-based applications to control various loads of the home. This project comprises a controlling unit and a monitoring unit; the control unit is placed at home, whereas the monitoring unit can be operated through a remote PC or Android mobile.
The control circuit is connected to the home and operated through a remote by using Android application from different place. A power supply block provides power to the entire control circuit. The physical parameters like light, temperature and soil moisture are given as input to the microcontroller.
When the light falls on the LDR during peak time, it sends the information to the microcontroller which further operates the relays to switch the lamps on. Similarly, when the temperature is below or above a certain limit, then AC will be turned on or off by the microcontroller through this relay, and, in the same way, for moisture sensing also. The status of all these parameters is displayed on the LCD as well as on PC or Android mobile through a Zigbee transmitter.
The receiver unit continuously monitors the physical parameters at home that are sent by the microcontroller through a Zigbee transmitter. The data is further transmitted to a PC through RS 232, and then it is displayed on the PC.
We can also monitor this information on an Android-based mobile phone through a WI-FI even on a PC as well. This system also allows sending the control signals to the home using the Android mobile remotely.
This is all about the Zigbee and Android-based projects in real-time applications. We appreciate the efforts of our readers for their valuable time on this article. Apart from this, for any help regarding any projects, you can contact us by commenting in the comment section below.