Mems based home appliance control

1. Head office Buildings, OP: 3nd floor, Krishna Reddy P: ICICI ATM, Ramalingapuram, Nellore
www.pvrtechnology.com, E-Mail: pvrieeeprojects@gmail.com, Ph: 81432 71457
MEMS BASED HOME APPLIANCE CONTROL
DESCRIPTION:
Micro electro mechanical systems (MEMS) (also written as micro-electro-mechanical,
MicroElectroMechanical or microelectronic and microelectromechanical systems) is the
technology of very small mechanical devices driven by electricity and it merges at the nano scale
into nanoelectromechanical systems (NEMS) and nanotechnology.
MEMS are separate and distinct from the hypothetical vision of molecular
nanotechnology or molecular electronics. MEMS are made up of components between 1 to 100
micrometres in size (i.e. 0.001 to 0.1 mm) and MEMS devices generally range in size from 20
micrometres (20 millionths of a meter) to a millimeter. They usually consist of a central unit that
processes data, the microprocessor and several components that interact with the outside such as
micro sensors. This MEMS works on i2c protocol and having SDA, SCL pins. Here
microcontroller acts as master and MEMS acts as a slave.
The aim of this project is to control the home appliances by using MEMS. The MEMS
will be tagged to the hand. Whenever the hand moves in a particular direction, the mechanical
movement of the hand will be recognized by MEMS. Here we consider 4 directions i.e. front,
back, left, right and stop. MEMS convert this mechanical hand movement into equivalent
electrical signals(X, Y, Z coordinates) and send it to the microcontroller. The communication
between microcontroller and MEMS takes place based on i2c protocol. In this protocol
microcontroller acts as a master and MEMS acts as a Slave. And the controller will also be
interfaced to 2 ac loads through relays. These loads will be controlled based on the signals
received by the MEMS, as per the code logic.
This project uses regulated 5V, 500mA power supply. Unregulated 12V DC is used for
relay. 7805 three terminal voltage regulator is used for voltage regulation. Full wave bridge
rectifier is used to rectify the ac output of secondary of 230/12V step down transformer.

2. Head office Buildings, OP: 3nd floor, Krishna Reddy P: ICICI ATM, Ramalingapuram, Nellore
www.pvrtechnology.com, E-Mail: pvrieeeprojects@gmail.com, Ph: 81432 71457
TECHNICAL SPECIFICATIONS:
HARDWARE:
Micro controller : AT89x series
Crystal : 11.0592 MHz
MEMS sensor
Relays
Loads
Power supply
Transformer : 12V step down
Filter : 1000uf/25V
Voltage Regulator : 7805, 7812
SOFTWARE:
Keil IDE
UC flash
Proteus
APPLICATIONS

3. Head office Buildings, OP: 3nd floor, Krishna Reddy P: ICICI ATM, Ramalingapuram, Nellore
www.pvrtechnology.com, E-Mail: pvrieeeprojects@gmail.com, Ph: 81432 71457
 Industrial applications
 Automatic control systems
BLOCK DIAGRAM:
POWER SUPPLY BLOCK DIAGRAM:
8
0
5
1
Power
Supply
Load1Relay1
MEMS
sensor
Stepdown
Transformer
Filter Regulator OutputBridge
Rectifier
Relay2 Load2

4. Head office Buildings, OP: 3nd floor, Krishna Reddy P: ICICI ATM, Ramalingapuram, Nellore
www.pvrtechnology.com, E-Mail: pvrieeeprojects@gmail.com, Ph: 81432 71457