Very Low Cost Remote Controlled Home
Automation
Surya Penmetsa
Electronics and Communication Engineering
NIT Warangal
Abstract- This paper will present the concept of efficiently
modifying the electrical system of an entire house into a remote
based one, with low cost.
Keywords- Arduino, ATMega328, ASIC, TSOP, Relay, Infrared
radiations.
I. INTRODUCTION
Even with technology evolving day by day, implementation
in day to day life is tough. For example, speech controlled
home appliances are already in action, but it still isn’t used
extensively; the main reason being cost and complexity.
Here, I have discussed the possibility of a very low cost
remote based system for a general house; the cost of which
would be around Rs.1000 and could further be reduced when
released in bulk. I have also provided details of the prototype
design, with which the accuracy of the system was tested.
II. COST EXPECTED
S.No
1
2
3
4
5
6
Component
ATMega328
Remote
Relays (15x)
TSOP1756(15x)
Transistors
5V adapters
Total
Cost
Rs. 225
Rs. 50
Rs. 300
Rs. 300
Rs.50
Rs.75
Rs. 1000
Fig1. The pin mapping of the controller in the product
B. The Remote
It is similar to the television remote we use in our daily lives.
Old television remotes can also be used for this purpose.
C. The IR Receiver (TSOP)
TSOP17xx are specially designed to decode a specific
frequency, such as infrared radiation at 38 KHz, and filter the
rest. So, it can receive the signals sent by the remote and send
them as to the controller without changing it.
The cost of the product could decrease up to Rs. 700 when
released in bulk.
III. HOW IT WORKS?
A. The Controller
This design incorporates the use of ATMega328 as the prime
controller. It will receive the data from the TSOP, process the
data, decode the IR Signal and then finally send the control
signals to activate the solid state relays.
The pin mapping of the controller is shown in Fig 1.
Fig2. TSOP17XX
D. Activation of Relays
The output signal from ATMega328 is fed to the transistor,
which acts as a current driver for the solid state relay. This
way, with a normal controller which works at 5V, we can
control a 230V AC signal.
IV. BLOCK DIAGRAM
ATMegs328 has 14 output pins. We can use ATMega2560 if
we need more output pins; up to 54 pins are available.
To be more specific, Pins 2, 3, 4, 5 were connected to Light
Emitting Diodes. Pin 11 was used to receive data from the
TSOP1738. An additional library, named IRRemote, was
downloaded from [3] has been used to decode the array of 0’s
and 1’s received. Later, the Light Emitting Diodes have been
replaced by a relay driven by a Transistor. The below picture
depicts the wiring of the circuit (Light Emitting Diodes are
used in the place of relays).
The circuit had reaction time as low as 0.5seconds which can
be improved by using an Application Specific Integrated
Circuit (ASIC).
V. PROGRAMMING
The Code (Written in Arduino0022):
#include <IRremote.h>
int RECV_PIN = 11;
IRrecv irrecv(RECV_PIN);
decode_results results;
int valueReceived;
void setup()
{
Serial.begin(9600);
pinMode(2, OUTPUT);
pinMode(3, OUTPUT);
pinMode(4, OUTPUT);
pinMode(5, OUTPUT);
irrecv.enableIRIn(); // Start the receiver
}
void loop() {
if (irrecv.decode(&results)) {
if(results.value < 1100)
{
digitalWrite(results.value-1023, HIGH);
Serial.println("pin 2 HIGH");
}
else if(results.value > 66500)
{
digitalWrite(results.value-66559, LOW);
Serial.println("pin 2 LOW");
}
irrecv.resume(); // Receive the next value
}
}
VI. PROTOTYPE DESIGN
ATMega328P/PU has been used in Arduino (FreeduinoV1.16)
environment to test the accuracy of the design. The code given
in the previous section has been dumped into the
microcontroller using Arduino 0022.
Fig3. The prototype design
VII. HARDWARE IMPLEMENTATION
A house can be equipped with this product within an hour,
thanks to its easy installation process. This design will be
replacing the current switch board of the house. The wires in
the switch board will now be connected through the relays.
VIII. PARAMETERS UNDER CONSIDERATION
A. Accuracy
The accuracy of the system can be improved by using an
Application Specific Integrated Circuit (ASIC) instead of the
multipurpose controller.
B. Space
It doesn’t need extra space. It will only be replacing the
current switch board.
C. Complexity
It is simple circuit with easy to understand installation
procedures as the design uses only one IC, which controls the
whole house.
IX. EXTENTIONS
A. Reprogrammable chip
The chip also gives an extra degree of freedom to the user, as
it is reprogrammable. The consumer will be given extra
options such as modify, create and save codes of a general
infrared remote. This way the consumer can control all the
appliances he/she owns with an existing remote, rather than
buying a specific new one.
B. Controlling Television/Air Conditioners
This can further be extended to televisions, air conditioners
and almost every technology that works with infrared remotes.
C. Using the Bluetooth/RF Module
Infrared radiations are directional in nature, which means that
the user has to point their remote to the TSOP receiver. This
can be overcome by using a Bluetooth module, to directly
control each appliance with a mobile phone.
REFERENCES
[1] http://arduino.cc
[2] http://www.ladyada.net/learn/sensors/ir.html
[3] https://github.com/shirriff/Arduino-IRremote