Arduino project · Smart doors and home · Medium
Daylight Window Blind
A servo opens the blind when it is brighter outside than inside and closes it otherwise.
What you will learn
- How to compare outside and inside light
- How a servo moves a blind
- How smart homes use daylight
How it works
LDR1 is outside and LDR2 is inside. When outside is brighter by 15 the blind opens (servo 90); otherwise it closes (servo 0). The Compare step checks one sensor against another, so you do not need to set a fixed number.
Try this next
- Open the blind only in the morning with a clock.
- Add a manual button.
- Add a rain sensor to close it in rain.
The simulator program and explanation on this page are original. The idea follows a classic Arduino project that students have built for years.
Parts: sensors and actuators (tap to show or hide)
Try the inputs (virtual sensors)
Pins (you can change them)
| Part | Arduino pin (change it here) | How to wire it |
|---|
Every wire, one by one
Red rail = 5 V from the Arduino 5V pin. Black rail = GND. The coloured wires carry signals. Match the wire colours on the drawing to this list.
| # | Colour | From (part and leg) | To |
|---|
Steps run from top to bottom, then start again. While the simulation runs, the active step is highlighted in green.
Quantities come from the parts you added. The store links open a search for that item on Robu.in, Amazon.in and ThinkRobotics, so you always see what is in stock today. Check the model, voltage and price before you order.
| # | Item | Qty | Search term | Buy / compare |
|---|
The PDF has the circuit sketch, pin table, every wire, sequence, full code, the parts list with store links, do’s and don’ts for each part, and the safety notes. The project file lets you come back and keep editing.
In the real world
A window blind
Change the light sliders. The blind opens when it is brighter outside than inside, and closes when it is not.
Tip: use the gold tab at the bottom of the circuit drawing to pull the real-world view up over the Arduino board. Your parts stay visible above it, so you can press a button and watch the real scene react.
- Outside light sensor = the daylight
- Servo = the blind motor