I am very proud of this project it took me 6 weeks to finish it that was because I did not have much of an idea how the circuits worked or the machines, when I first started, but now I believe the possibilities are endless with this light. Rather than, using ninja turtles like I did for the pictures, someone could use sports pictures like football player having the ball in one picture, throwing it in another, and the ball spinning in the air, than finally having a player catch it in the last picture. You could make pictures for hockey, soccer, favourite shows, live action shots of the family the possibilities are endless. This is something that will not only give the child or the person your making it for very excited, but will also push your own abilities to learn how to make circuits work, use a laser cutter, and if your really ambitious like I was use a CNC mill to make your own circuit board.
Step 1: Building Your Curcuit
For the night light you need to get a few things:
18 gauge wire in 3 different colours (Preferably red, black , and white)
2- 555 timer chips
1- 4 bit bi-directional shifter register
12- LED's (colour of your choice)
1- voltage regulator
1- potentiometer (2-20000)
3- capacitors ((1uF)(4.7uF)(10uF))
7- resistors ((2x1900 ohms)(10000 ohms)(3300ohms)(230 ohms)(22000 ohms))
1- 9v-200ma step-down transformer
1- 18"x24" 1/4" plywood
1- 18"x24" 1/4" acrylic
you will start after collecting all of the supplies and designing the circuit for how fast you want it to flash each frame. you will hook up your circuit just like the one that I sketch on paper in the pictures. When hooking everything up make sure you use one colour for positive connections, a different colour for negative connections, and a different colour for the pin to pin connections. I did not do this and it cost me a lot of time and agony during the trouble shooting process. Do not worry about hooking up the Astable circuit yet we need to first make sure that the LED's are sequencing correctly, than we can add the Astable circuit that allows it to trigger when the light is turned off.
After you get everything hooked up just like it shows on the sheet. Use a power source that will have the voltage close to the one that you choose for you transformer (if you cant find a 9v-200ma) to test the circuit. I found the 9v-200ma one lying around from an old broken air mattress pump. The reason that you want to do this is because if you us 6v to test your circuit and get everything going perfectly without anything running to hot, burning it out. You will run the risk of over heating the chips when you put on a higher power source such as your transformer. While you are testing the circuit feel the chips to make sure they don't get hot. if they do you remove the power source immediately and prey you didn't burn out the chips while looking for higher resistance to put in your circuit. If everything works out as planned we can construct the Astable circuit so that it turns on when the lights are turned off. The diagram will be in the pictures disregard the resistances and capacitances and use the ones that I have in the materials list and just attach the pin 3 from the Astable to pin 2 on the other 555 timer (monostable). test how it turn on and off with the light and adjust for your sensitivity by adding more or less resistance in parallel with the photo resistor.
Step 2: Making the Base and Cutting Out Your Pictures
It is easy to make the pictures, the best way to do this is find pictures that have high resolution and not very much going on in the picture. As you can see from the photos the picture that I chose for this project had a little too much going on. this makes it hard to see the pictures that are behind some of the others. If you are having no luck try searching for vector images of what you want. Import the pictures to the platform you use for engraving in a laser cutter. I use Corel draw for engraving and Inkscape to edit and make my images. Once you have the images you want load them up and create boxes 5"x8" , order the pictures so they will be seen from the front without other pictures hindering each other. Go into print preview and general settings that preferences for your engraver. from here you will select auto focus, raster, than settings 100 speed/ 45 power.
Go back to the general settings and select mirror. Once done place 1/4" acrylic into laser cutter removing one side of the protective adhesive, hit print and press go on the laser engraver. let it engrave tell the groves are deep 2 to 3 times, while it is engraving go back to the corel draw, drawing screen. and select the boxes and make them hair line, go to print preview, general settings, preferences, than select vector this will cut the pictures out 12 speed/ 100 power/ 5000 frequency, press print and the green bottom on the laser engraver.
Making your own box can be done using either corel draw or inkscape, or taken from the diagram that I made. once the drawing is complete upload it to corel draw repeat the steps to cut it out 35 speed/ 75 power/ 500 frequency this will take 2 to 3 times to cut the box out of plywood.
Step 3: Milling/ Making the Circuit Board
I chose to make my own circuit board because I wanted it to look clean even though the board turned out to be very messy and I need to practice my soldering skills a little. Any ways, I figured I would show what I did because it took the longest out of any steps to make this project. You can make a different board using a standard pin pcb to solder everything on. If you wanted more details on the methods or code to make your own circuit board just message me.
solder the connections to your pcb in the same way that it is set up on your bread board. rather than soldering the LED's to the board I recommend soldering wires so that the LED's can be stretched to fit into the slots where you make the pictures stand up to display. Make sure that you put 3 LED's in parallel to disperse the light efficiently to light the pictures. Do not solder the photo resistor on the board just yet.
Step 4: Assembling the Nightlight
After the board is made if you designed your box like I did there will be a small hole on the side to fit the transformer cord through and solder the wires to the positive and negative pins on the pcb. Stretch the LED's so that they fit like they are suppose to under each of the pictures in the sequence that the LED's go off to make the pictures look like they are moving. fix the LED's under where the acrylic will go so that if the night light is bumped they wont move. Drill 2 small holes on the side right next to each other to fit the photo resistor to solder onto the pcb.
Plug in the night light, place the pictures in the slots, turn off the light and look back at your home made night light.