LED Cloud

Hello!

This time I want to share my recent project – LED cloud for newborn child. Main function of LED cloud is to light and dim randomly LEDs to simulate star heaven. Additionally there will be other lighting features like regular single color light, rainbow ect.

You’ll need:

• Plywood (120x60 cm)
• Plexi (120x60 cm)
• Cork strips
• Addressable LED strips
• Zink wires
• Insulated wires
• Power cables
• Data cable (6 wires)
• White paint
• Blue paint
• Hot glue
• Hooks
• Wood screws
• Universal enclosure
• Arduino nano
• Prototype wires (different colors)
• Power supply 230/5 V 6A
• Power switch
• Goldpin strip
• Prototype board
• IR sensor TSOP31236 36kHz
• LED red color
• Resistors 470 Ohm and 200 Ohm
• White plastic pcv strip
• Some heat shrink tubes
• Paint strip for curves
• Acrylic filler

We need to draw cloud shape on plywood. I used for that pot lids with different diameters. I sticked plywood and plexi together and cut the shape with jigsaw.

After that I sanded edges to have them soft and free of burrs. Then I sticked cork strips to plywood edges with two layers. This will give some distance from plexi to plywood and make light much more diffused.

Next I need to arrange LEDs on cloud surface. To maintain the same distance I drew lot of cricles and each LED will be sticked in center of individual circle. Remember that this is specific type of addressable LED – W1281b you need to pay attention on direction of LED. Each signle strip has marked arrow. You need to keep direction of arrows in correct way.

After sticking all LEDs on plywood surface there is going to be hard part – LEDs soldering. I used for that zink wire and in some cases insulated wires. It is very time consuming but I didn’t found any other suitable LED strips with such distance.

After soldering approx. 15 LEDs I checked them with test sequence with my test Arduino (test stand) just to see if everything is ok. Note that if you won’t solder wires correctly LEDs can light in strange way (blinking, different color ect). If you have LEDs form different supplier or even different batches you may notice very small differences in color. It is normal and for me it’s ok, but if you want to have each LED in the same color you need to make sure you use LEDs form the same production batch. Each LED consumes at maximum 60 mA of current. In my case I have in total 93 LEDs which gives me around 5,5 A current consumption for whole cloud. Reason of that is relatively low voltage of LEDs – 5V. You need to use special power supply 230V/5V or use any other output voltage with step down regulator. Also good practice is to make some additional power supply points in the middle of the strip to distribute power effectively. You can find tip on Adafruit webpage that you should add additional power source point for each 1 m of LED strip to have best color effects. For more info and tips visit Adafruit webpage.

After soldering all solder joints have been protected with hot glue.

Finally solder power cables, check everything twice and you’re ready for painting. I used white acrylic paint / two layers. Then you need to attach plexi. I drilled some holes and attached plexi with wood screws. I masked screw heads with acrylic filler.

Then I sticked curved masking tapes and paint edges with blue paint – 3 layers.

Now it is time to put power supply and electronics together. I realized that my cloud need to be somehow controlled. I was thinking about Bluetooth and controlling it with Android app but to be honest it is not handy method.

I wanted to learn something new so I thoung that we can control it with IR pilot.

I prepared universal enclosure, drilled necessary holes for cables and attached with hot glue power supply. Next I connected all wires together according to schematics. I prepared additional board for power distribution inside enclusure. IR sensor should be able to attach to furniture or wall. I decided not to put it inside enclosure. Additionally I put red LED as indicator that shows IR sensor response. I soldered LED and IR to wires. On other side I soldered goldpin female connectors. Now is time to connect everything to Arduino nano. LED is to 13, IR is to 2, digital LED is to 6. See details on schematic. After that you can program Arduino.

At the beginning of programming I prepared animations functions and have tested each separately. I also program initialization animation which will be showed after turning on LED cloud.

I also tested separately IR functionality with the pilot. Download IR library (IRremote.h - read the manual), use check ir program to identify you pilot keys. Turn on Serial Monitor, press pilot buttons and see what characters are showing on serial monitor. Copy it, you will need to hardcode them. By pushing buttons on pilot you’ll be able to change programs. I used for that interrupst. For Arduino nano interrupt pin it 2 or 3 so this is the reason why I connected IR signal to 2. For some reason during first attempt interrupt functionality didn’t work. After lot of googling I found solution for that.

Finally I programmed light functions. For details check attached code.

Last thing is to attach cloud to the ceiling. Plywood will have 3 attachemnt points. I drilled to the ceiling 3 L shaped hooks, but before installing them I bent them little bit on vise to make sure that cloud won’t move when attached to ceiling.

Next I conducted power cable with cable channel installed on the wall. After connecting the power we are ready to turn on the clodu.

Check the final effect - attached photos and movie. I switch lighting modes with TV pilot. IR sensor is attached to the wall in the middle of the room so I can reach it from each corner.

Hope you like it!

Best regards

Maciej