In this modern world, we all are enjoying the gift given to us by nature through the natural resources like Water and coal which is electricity.
We cannot even imagine our life without power. Power is really the greatest power for us these days. Almost all household appliances, office machinery are running with the help of electricity.
So, it is the time to do something for our environment by saving electricity. So, we must use it wisely and efficiently.
Mostly in households appliances power is wasted from fridges in kitchen.
Through this project, you are going to build a unique project that can remind you if you didn’t close your refrigerator completely with an alarm.
You will need an Arduino Uno board for interfacing microcontroller with the LDR sensor and Buzzer.
We will place the LDR sensor inside the Fridge near the light, whenever the door is opened the light inside fridge will be turned on.
So that the LDR sensor detect the light and it starts counting time.
After certain time limit, if the door was not closed (LDR sensor value didn’t change) the buzzer will start giving sound.
In addition to this, we can add Wi-Fi module, to upload the data into remote cloud, to access it from anywhere in the world.
You will program the microcontroller in such a way that say whenever the value from LDR sensor changes,
microcontroller starts counting and after certain time MC will check the LDR value if it is High, buzzer wont trigger,
But if its value is low, buzzer will be triggered immediately.
You can also innovate the system further to send a notification to a user at any part of the world via SMS or email.
Arduino/Genuino Uno: The digital and analog input/output pins equipped in this board can be interfaced to various expansion boards and other circuits.
Serial communication interface is a feature in this board, including USB which will be used to load the programs from computer.
LDR (Light Dependent Resistor): An LDR can be called as variable resistor controlled by intensity of light.
Whenever the LDR is in very low light, the resistance value of the LDR will be very high (in Mega Ohms).
Similarly Whenever the LDR is under normal light the resistance value of the LDR will be very less comparatively (in order of 10^2 Ohms).
7805 IC: IC 7805 is an integrated circuit which can used as a voltage regulator.
It is an electronic circuit that provides a stable DC voltage independent of the load current, temperature and AC line voltage variations.
A voltage regulator may use a simple feed-forward design or may include negative feedback.
Depending on the design, it may be used to regulate one or more AC or DC voltages.
Buzzer: A buzzer is a device gives audio signals, which may be mechanical, electromechanical, or piezoelectric.
Typical uses of buzzers and beepers include alarm devices, timers, and confirmation of user input such as a mouse click or keystroke.
IN4007 IC: The 1N400x (or 1N4001 or 1N4000) series is a family of popular 1 A general-purpose silicon rectifier diodes commonly used in AC adapters for common household appliances.
Its blocking voltage varies from 50 volts (1N4001) to 1000 volts (1N4007).
Wi-Fi Module : ESP8266 Wi-Fi module is generally used to establish the wireless communication between the devices.
But this module is not capable of 5-3V logic shifting and will require an external logic level converter.
Interface LDR and Buzzer with Arduino.
Power the circuit and Upload the code.
Place the LDR properly so that it should detect the light inside the fridge.
Check the output by opening and closing the fridge door
Upload the data into remote cloud for analysis from anywhere.
Arduino IDE : You will be needing Arduino IDE software to write and upload the programming logic onto the Arduino Uno board
Thingspeak : Also, you need to create an account in the ThinkSpeak IoT platform to integrate the system onto the cloud and store the data online
Programming language: Arduino Programming (C++)
Kit required to develop Fridge Door Alarm with IoT: