This Instructable shows you how to make a nifty Arduino (ATTiny) powered animated night light. This design uses inexpensive LED strips in 3 separate circuits. The 'sun' LEDs stay on constantly, while the 2 'cloud' LEDs slowly fade up & down in a pseudo-random way.
Materials needed: 9" x 12" X 1/4" white foam, 3" x 5" x 1/4" yellow foam, ATTiny, Arduino UNO (or other ISP programmer), 7805 voltage regulator, 3 qty 2n4400 NPN transistors, 10 uf capacitor, 8-pin socket (optional), 1" x 1" perf-board (optional), 24" length of LED strip lights (3528 or equivalent), 12v DC power adapter, 24 GA hook-up wire, glue, soldering iron, solder, razor knife.
Skills needed: soldering, programming, electronics, cutting, gluing.
Step 1. Find or draw 2 images of a cloud, such as those included here. These could be identical or different.
Step 2. Cut the white foam in the shape of the selected clouds.
Step 3. Cut the yellow foam in a semi-circle for the sun.
Step 4. Using the scrap foam material, cut about 6 small squares (1/4") for spacers. These spacers will create a space for light to escape, creating a 3D look.
Step 5. Cut the LED strips at the indicated location on the strip to fit beneath each foam cloud and the foam sun. If multiple strips are used, pre-solder them together with 24 GA wire before attaching to the foam clouds (see photo). Also, solder 2 lengths of wire to each LED circuit long enough to reach the perf-board, which will have the electronics mounted to it (about 6 inches). Test each LED circuit with your 12 volt power adapter to make sure they work.
Step 6. Glue the LED strips to the back side of each cloud/sun cut-out. Most LED strips have adhesive on the back, but I have found that additional glue is needed for a permanent job. Gorilla glue works well.
Step 7. Glue the pre-assembled clouds together using the square spacers from step 4. Add a short length of wire to the bottom cloud (closest to the wall) for hanging purposes. This wire will mate to the power adapter, to which I have attached another foam block cut at an angle (see photo).
Step 8. Build the circuit shown in the schematic, and mount onto the perf board (see photo).
Step 9. Program the ATtiny 85 with the code provided. Note: Use of Arduino UNO as a programmer is optional, but is a rather simple way to program the ATtiny. See https://www.instructables.com/id/Turn-Your-Arduino-... for details.
Step 10. Insert the ATtiny into the socket and test by plugging in the power supply and observing the show!