Transcript AUTOMATIC ROOM LIGHTCONTROLLER byV SwethaB …

AUTOMATIC ROOM LIGHT
CONTROLLER
by
V Swetha
B Deepthi Priya
as
Indian Institute of Technology
Hyderabad
Functions of the controller
This controller performs the task of controlling
the room lights as well as counting the number
of persons in the room accurately
The total number of persons in the room is
displayed on the seven segment display
When a person enters into the room , the
counter is increased by 1 and the light glows
In the absence of person in the room , the light
automatically goes off
Circuit Diagram
IR Sensor
A pair of LEDs can be used as IR sensors.
The first IR LED is used to emit signals
The second one receives the input and
transmits the signals.
When an object comes within the range of the
emitted IR , it reflects the IR back to the
receiving LED
Then a signal is produced from the IR.
Microcontroller
This is the CPU of our project
We used AT89S52 microcontroller
It receives the signal from the sensors
This signal is operated under the control of
software which is stored in ROM
Microcontroller At89S52 continuously monitor
the IR receivers
When any object passes through the IR
receivers , then the IR rays falling on the
receivers are obstructed
This obstruction is sensed by the
microcontroller and count is displayed on
seven segment display.
Crystal Oscillator
It is an electronic circuit that uses the
mechanical resonance of vibrating crystal of
piezoelectric material
The material creates an electrical signal with a
very precise frequency
Block Diagram
89S52
I
R
T
X
I
R
R
X
pP2.0
P2.1
RELA
Y
Advantages and future development
It can be used in various rooms like seminar
halls , where the capacity of the room is limited
and should not be exceeded
It can be used in our homes because we often
forget to switch off our room lights
It helps in energy conservation
In future , we can send this data to remote
areas using mobile or internet
Voice alarm system can be used to indicate
that room is full & person can’t enter inside