Remember, Turn Off the Lights, Save the Earth.

This device helps me learn to develop a habit to turn off lights when I leave my room.

The device is simply built by Arduino, mainly using a light sensor, an ultrasonic distance measuring instrument, and a LED light bulb.

It reminds me to turn off the light if I forget, by lighting up the LED light bulb sticking outside the door.

Supplies

Light sensor

Ultrasonic Distance Measuring Instrument

LCD Screen

LED light bulb

Alligator Clips with Pigtails

Various kinds of Wires

Nice looking box

Step 1: Structure of the Device

There are 5 main parts that make the device work:

A-Light Sensor: senses the value of the rays of light(is the light turned on or off) and arranges by the coding

B-Ultrasonic Distance Measuring instrument: detects the distance of the door, and arranges by the coding the main point is to detect if the door is open or not

C-LCD Screen: shows the number of distance, to help the code setting of the Ultrasonic Distance Measuring instrument

D-LED Light Bulb: the object that lightened, easy to notice as a reminder

E-Alligator clips with pigtails: makes the LED light bulb able to reach outdoor

Step 2: Coding

1. set up the LCD Screen to show the distance that the Ultrasonic Distance Measuring instrument detected.

2. create an 'if/else' logic with two conditions:

a) if the value of rays of light is higher then 500--- the light turned on

b) if the number of distance is shorter then 93--- the door opened(leaving the room)

-if a) & b) conditions both fit--->the LED light bulb outside the door will light up(reminds you to turn off the light)

-if either one of them a) or b) conditions don't fit--->the LED light bulb outside the door will not light up(you still in your room or you remember to turn off the light or both)

Step 3: Change the Appearance

No one would want a device full of wires on the ground of their room.

Simply put the device into a box that looks nice.

*It is important not to put the sensor and detector in the box or it cannot work.

Step 4: How It Works in Reality

When I leave the room with lights on, the reminder LED light lights up.

When I leave the room with lights off, the reminder LED will not work.

Step 5: Reflection

This project helps me learn to develop a habit to turn off light when I leave my room. And I learned to create a device on my own from designing to making. It also improved my ability to Arduino skills and to manage a crisis. I think I have way better skills then I thought before and it raises my confidence. I am looking forward to the next project and seek a greater challenge.