Introduction: Humidity and Temperature Reacting Lightsource

This project came out of my desire to get an active temperature readout when i'm in my room. not being fond of trying to look at a tiny screen across the room, i wanted something i could just sense in my room. with a simple glance at the light in my room i could discover what temperature it is.


1. Arduino Nano (could be made with any Arduino like the UNO)
2. Cables (estimates will follow)
3. temperature and humidity sensor (i got both in one module, but you could have them seperate)
4. triplex 3mm thick (for the casing. i used 80x80mm)
5. ledstrip
6. power supply (for the 74LEDs i have i needed 5volts and 3 amps)
7. laser cutter


light with RGB controlled by humidity and temperature

controll via internet
lasercutted decoration

make portable setup
display temperature online

controlling light localy
automate other stuff based on temperature and humidity

Step 1: Connecting It All

after looking some on the internet about this sensor i saw that i needed a library to have quick acces to the sensor. the DHT library is responsible for handling the sensor. we only have to make its object and get values from them. explanaition on using this is in the code of course. :)

so i connected it to my arduino and got some good readings with the testsketch found here:

besides that, i also tested the LEDs with this library:

connected as the schematic indicates, everything seemed to work stand alone. the combining of this will happen in the code section.

Step 2: The Case

i made a neat little cutout for my arduino nano. this way the cables and everything was neatly packed into a box. special holes so the sensor is outside and the datacable for the LEDs is there, cutout for the USB and thats pretty much all there is to this box. simplicity gives some charm :)

after some superglue and a little patience, my box was neatly assembled.

i have included "" if you want to have the same box i have.

Step 3: The Code

the code is available on the following link:

in the code i explained what everything does in comments.

you will also need these library's to get this too work and go to arduino>sketch>library>add .ZIP library

Step 4:


the project works neatly and i have something to light my room with that also tells me how hot and humid it is

importand to note is that the arduino and the LEDs HAVE to share a common ground. if they do not share a common ground, the signal will distort and you will have carnival lights. very pretty, but not very usefull.

i hope you have fun building this project too :)