ECE 4760: Final Projects

Smart Home System

A wireless, voice-controllable, household system.

Jiayuan Wang (

Sheng Zhang (



"A wireless system to control the lights, fans and other home devices by human's voice."

Project Soundbyte

Motivation    top

We design a smart home control system which allow people control their home devices by voice command at home. This is a wireless, voice control system. People could control almost all the facilities at home including lights, fans or even back ground music. Right now, the basic function of lights control, fan control and music control have all been implemented. Except for basic turning on and off of fasilities at home, we also realize the function of fixed-time control, and error detection when some device is broken. The system is quick enough for respond all the commands.

Our smart home system is a simulation product for the future life. The purpose of it is to make people's lives more convenient. To replace turn on or turn off on switches by hand for current product, our system is controlled by voice. That should be a trend for the future 10 years which we believe that it is coming to real product soon. How to make people’s life more convenient, more comfortable, more safe and how to save more energy will be the series of questions we will care, discuss and design in our project. Just imagining, after you cook a big pot soup and want to leave the kitchen, you don’t have more hands to turn off the kitchen’s light. If our project becomes a mature product, you can set up our system in the home, you can turn off the lights by voice when you hold a pot soup at the same time. When you read the book in bed at night, you are not sure when you will sleep, you can tell the system when you want the light turn off, the timer in the system will help count the time and turn off the lights with the time you have set.

Early Work    top

Why we choose wireless signal transmission?

When someone gets home and wants to enable light, fan, music at home, he may use his voice to control his household appliance. However, the transmission distance of the voice is short and it is even hard to recognize what you said when there is some noise mixed with the signal. Sometimes the voice recognition chip will send out wrong instructions because of the noise outside. So we decide to place a central control unit in the center of the room and send digital signal wirelessly to where other microcontroller is. Once the receiver gets the signal, it will operate on/off/dimmer function which has been programmed in it previously. As xbee could transmit at most 1000 meters, this method avoids the distance problem and signal interference problem.

Why we choose xbee?

XBEE promises many advantages over existing remote control solutions, including richer communication and increased reliability, enhanced features and flexibility, interoperability, and no line-of-sight barrier. In our project we use XBEE for point to point communication. It is efficient and enough to be used in household. The transmission of signal won’t be blocked in a long distance and even by a wall. Due to this spec of the xbees, we may put the center voice recognition microcontroller in the center of one household so that it could communicate any other microcontroller (which has xbee receiver with it) and enable different functions by sending out different instructions. Here, I use different characters, like “a”,”b”,”c” etc to represent controls on fan, lounge room LED and bedroom LED.

X-CTU is the program provided by digi to initialize and test with xbee communications. We change the baud rate to 9600, set the same pin number for two xbees through the program so that it is ensures there will be no other xbee or RF devices interfering the wireless communication between two our two xbees.