This redesigned 8x8x8 LED cube kit includes two custom PCBs to make building the kit much easier. The LED cube will be installed on the base PCB and all of. Led Cube 8x8x8 - Download as PDF File .pdf), Text File .txt) or read online. the light intensity punch and when used in a 3D LED cube must be viewed in a dark To build an accurate 3D LED Cube Matrix with evenly spaced and aligned .
|Language:||English, Spanish, Arabic|
|Genre:||Health & Fitness|
|ePub File Size:||30.54 MB|
|PDF File Size:||12.62 MB|
|Distribution:||Free* [*Regsitration Required]|
This Instructable is the most comprehensive step-by-step guide to build an 8x8x8 Led Cube ever published on the intertubes. It will teach you. LED Cube 8x8x8: Create your own 8x8x8 LED Cube 3-dimensional display! We believe this Instructable is the most comprehensive step-by-step guide to build. 8x8x8 Arduino LED Cube: This is a fairly simple project, but it is time consuming and well worth the end product!!! 8x8x8 LED caite.info Download. Tip.
Output Enable: We solder them as continuous solder lines. Even with the heat sink that you see in the picture, it became very very hot. You'll see why If you do, please post a video in the comments! If any of the layers or columns seem to light up in the wrong order, you have probably soldered the wrong wire to the wrong layer or column. When the current on the output pins are switched on and off, this can cause the voltage to drop enough to mess with the internal workings of the ICs, for a split second.
The latch pin CP on the latch is a rising edge trigger. So when port B outputs 8 or in binary. For the purposes of this instructable. Wire up your cube accordingly. You can also use a serial-in-parallel out shift register to get 64 output lines.
We went with the latch based multiplexer because we had 8 latches available when building the LED cube. If it had been an active HIGH chip. The way you would normally load data into a chip like this. This uses a lot of CPU cycles. This chip has two inputs may also have an output enable pin. To trigger the right latch. All the clock inputs are connected together and connected to a pin on another IO port.
In the previous solution. Everything is shifted one position to the right assuming that Q0 is to the left. Feel free to use this solution instead if you understand how they both work. You are probably thinking. The 74HC now outputs the following sequence: We simply connect the data input of each shift register to each of the 8 bits on a port on the micro controller. This setup will use 9 IO lines on the micro controller. Q5 into Q6. The state of the data input line is shifted into Q0.
The following pseudo-code will transfer the contents of a 64 bit buffer array to the shift registers. In this setup each byte will be distributed over all 8 shift registers. That means that the output that is active is pulled LOW. At over mA and 12V input. In addition to that. Cube drawing almost half an amp at 5 volts. Power supply considerations This step is easy to overlook.
We later removed this chip. We now use a regulated computer power supply to get a stable high current 5V supply. To calculate the current draw of your LEDs. Multiply this number by But remember that this circuit will draw 64 times the mA of your LEDs if they are all on. Our first attempt at a power supply was to use a step-down voltage regulator.
We have 12V output. External hard drive enclosures are especially nice to use as power supplies. This is what we have been using to power the LED cube.
We won't get into any more details of how to make a power supply here. That is the kind of plug you find on hard drives before the age of S-ATA. PC power supplies are nice. They already have a convenient enclosure. About 15 bucks will get you a nice PSU.
Build a power supply A couple of years before we built the LED cube. We use the second 5V output to power an 80mm PC fan to suck or blow fumes away when we solder.
Inside here is a small powersupply that used to supply the SCSI hard drive that was inside. This will power it up. I'm sure you can find another instructable on how to do that.
Used a Molex connector so we could disconnect the cube easily. If you want to use an ATX power supply. Old SCSI disk 2. Power supplies have a lot of wires. The only thing you have to do is to add external power terminals. Therefore we strongly recommend using diffused LEDs. Shipping them back to China to receive a replacement would have taken too much time. So many choices. Clear LEDs also create another problem. But keep in mind that the quality of the product may be reflected in it's price.
We actually ordered diffused LEDs from eBay. The cube design in this instructable uses the legs of the LEDs themselves as the skeleton for the cube. Our recommendation is to use 3mm diffused LEDs.
Maybe we should have taken the hint. A diffused LED will be more or less equally bright from all sides. To compensate for this. With 3mm round LEDs. Defusing is something you do to a bomb when you want to prevent it from blowing up.
This creates some unwanted ghosting effects. If your cube is made up of clear LEDs. These are the ones we ended up using http: We went with 3mm LEDs because we wanted the cube to be as "transparent" as possible. It works fine. We ended up using resistors of ohms. If you look in the data sheet. While you are waiting for your LED cube parts to arrive in the mail.
This gives you 6. BAD This is not what we ordered! Damn you ebay! Diffused LED. If all the LEDs on one anode column are on. You will find this line: You have to keep within the specified maximum mA rating for the output pins.
Choose your resistors There are three things to consider when choosing the value of your resistors. In order not to exceed this. If your LEDs draw 20mA each. GOOD This is what we expected to receive. The only transistors we had available had a maximum rating of mA. Seeing all the way through to the furthest layer wouldn't be a problem. We had seen some people using metal rods for their designs.
Add 1mm margin for soldering. Viva la resistance!! Choose the size of your cube We wanted to make the LED cube using as few components as possible. Our recommendation is to use the maximum spacing that your LED can allow. We could have made the cube smaller. Many of the metal rod designs also looked a little crooked. By choosing a LED spacing of 25mm. We figured that the easiest way to build a led cube would be to bend the legs of the LEDs so that the legs become the scaffolding that holds the LEDs in place.
The episode was about how they make steel wire. Get a firm grip of each end of the wire with two pairs of pliers Pull hard! You will feel the wire stretch a little bit. We remembered that the wire was totally straight and symmetrical after being pulled like that.
By making the 4x4x4 version first. We recommend that you do the same thing.
We tried to bend it into a straight wire. You only need to stretch it a couple of millimeters to make it nice and straight. Here is how you do it.
Remove the insulation. The only wire we had was on spools. Then we remembered an episode of "How it's made" from the Discovery Channel. Before we built the 8x8x8 LED cube. So we figured we should give pulling a try. Check out our 4x4x4 LED cube instructable for instructions on building a smaller "prototype". They start out with a spool of really thick wire. This would probably be a lot easier. Our first attempt at this failed horribly.
Practice in small scale Whenever Myth Busters are testing a complex myth. If you have a vice. These indentions will prevent the drill from sliding sideways when you start drilling. If the hole is too snug. You don't want it to be to tight. All done. If you make a small indentation before drilling. We used this LED to test all the holes. A steel wire will be soldered in here in every layer to give the cube some extra stiffening.
If the holes are too big. Everything but the kitchen sink? We sort of used the kitchen sink to hold the jig in place. Even with careful soldering. Touch the part you want to solder with the side of your iron where you just put a little solder. We used a 0. Let the target heat up for 0. At this point the LED is already very hot. So we decided to test every LED before using it. Continue with the next LED and let it cool down for a minute. Apply a tiny amount of solder to the tip.
Don't use solder without flux. We tested some of the LED before we started soldering. LEDs don't like heat. Mistakes and cool down If you make a mistake. Wipe your iron clean. Solder We recommend using a thin solder for soldering the LEDs.
The last thing you want is a broken LED near the center of the cube when it is finished. We considered these things before making a single solder joint. Soldering iron hygiene First of all. Some of the LEDs didn't work after being soldered in place. Are we paranoid? When building the 8x8x8 LED Cube.
You only need to apply a little bit. You might also want to have another LED with its own resistor permanently on the breadboard while testing. We also tested every LED after we finished soldering a layer.
This little gadget is great for cleaning your soldering iron Step We haven't experienced this. This gives you a lot more control. We found a couple of dead LEDs and some that were dimmer than the rest. If your solder is very old and the flux isn't cleaning the target properly. Having a clean soldering tip makes it A LOT easier to transfer heat to the soldering target.
Only the solder that is touching the metal of both wires will make a difference. Even if you are in the middle of soldering. This means that you have to take some precautions in order to avoid broken LEDs.
Soldering speed When soldering so close to the LED body. Remove the soldering iron immediately after applying the solder. A big blob of solder will not make the solder joint any stronger. This makes it easier to spot differences in brightness. Get out your breadboard. The first and second layer from the outside can be fixed afterwards.
That means wiping it on the sponge every time you use it. This might be less of a problem if you are using LEDs that are more expensive.
Do not try again right away. If the tip of your soldering iron looks like this. Whenever the you see the tip becoming dirty with flux or oxidizing. The tip of your soldering iron should be clean and shiny. Simply grabbing both ends of the layer and pulling would probably break the whole thing if a couple of the LEDs are stuck.
Solder all the joints. Rinse and repeat until you reach the left LED. Do this for both braces. We used one bracing near the bottom and one near the middle. Fine tune the alignment and solder the other end in place.
Repeat 8 times! Note on images: If you are having trouble seeing the detail in any of our pictures. Make sure the legs are bent in the same direction on all the LEDs. If it is still stuck. Start by lifting every single LED a couple of millimeters. Depending on the size of your holes. Then place the one to the left. Just enough to feel that there isn't any resistance. Looking at the LED sitting in a hole in the template with the notch to the right. Repeat until you reach the bottom.
Multimeter connected in series to measure mA. Take a straight peace of wire. Start by placing the LED second from the top. We leave this in place and use it to connect ground when testing all the LEDs in a later step. On the image page. When all the LEDs are freed from their holes. You will need a steady hand when soldering freehand like this. At the top of each layer each LED is rotated 90 degrees clockwise.
At this point the whole thing is very flimsy. That way your hand can rest on the wooden template when you solder. All our close up pictures are taken with a mini tripod and should have excellent macro focus. Just mentioning here so you don't remove the layer just yet. On the column to the right this leg will stick out of the side of the layer. It is convenient to connect ground to it when testing the LEDs.. About 1mm overlap. LED ready to be soldered. Don't remove the leg that sticks out to the side.
And then the rest. Start with this row 2. We marked off where we wanted to have the midway bracing. Look how nicely they line up. Then do this column 3.
Almost done. Brace Image Notes 1. We strongly recommend that you test all LEDs before proceeding. Connect a wire to 5V through a resistor.
Connect ground to the tab you left sticking out at the upper right corner. Ground connected to the layer 2. Take the wire and tap it against all 64 anode legs that are sticking up from your template. If a LED doesn't flash when you tap it. If everything checks out. If you look at the LEDs in your template from the side. This is better Image Notes 1. This isn't going to be a very nice LED cube! You want all the legs to point straight up. You now have a perfect layer that is ready to be removed from the template.
While looking at the template from the side. We use a 4x4x4 cube here to demonstrate. Pin straightening paid off. Then rotate the template 90 degrees.
To make a solder joint. This is enough for the leg to bend around the LED below and make contact with it's anode leg. Make a bend in the anode leg towards the cathode leg approximately 3mm from the end of the leg.
The first two layers can be quite flimsy before they are soldered together. You may want to put the first layer back in the template to give it some stability. In order to avoid total disaster, you will need something to hold the layer in place before it is soldered in place. Luckily, the width of a 9V battery is pretty close to 25 mm. Probably closer to We taped over the battery poles to avoid accidentally ruining the LEDs we were soldering. We had plenty of 9V batteries lying around, so we used them as temporary supports.
Start by placing a 9V battery in each corner. Make sure everything is aligned perfectly, then solder the corner LEDs. Now solder all the LEDs around the edge of the cube, moving the 9V batteries along as you go around. This will ensure that the layers are soldered perfectly parallel to each other.
Now move a 9V battery to the middle of the cube. Just slide it in from one of the sides. Solder a couple of the LEDs in the middle. The whole thing should be pretty stable at this point, and you can continue soldering the rest of the LEDs without using the 9V batteries for support. However, if it looks like some of the LEDs are sagging a little bit, slide in a 9V battery to lift them up!
When you have soldered all the columns, it is time to test the LEDs again. Remember that tab sticking out from the upper right corner of the layer, that we told you not to remove yet?
Now it's time to use it. Take a piece of wire and solder the tab of the bottom layer to the tab of the layer you just soldered in place. Connect ground to the the ground tab. Test each led using the same setup as you used when testing the individual layers.
Since the ground layers have been connected by the test tabs, and all the anodes in each columns are connected together, all LEDs in a column should light up when you apply voltage to the top one.
If the LEDs below it does not light up, it probably means that you forgot a solder joint! It is A LOT better to figure this out at this point, rather than when all the layers are soldered together. The center of the cube is virtually impossible to get to with a soldering iron.
For the next 6 layers, use the exact same process, but spend even more time aligning the corner LEDs before soldering them.
Look at the cube from above, and make sure that all the corner LEDs are on a straight line when looking at them from above. Rinse and repeat! Instead, we modified the template to work as a base for the cube. We encourage you to make something cooler than we did for your LED cube! For the template, we only drilled a couple of mm into the wood. To transform the template into a base, we just drilled all the holes through the board. Then we drilled 8 smaller holes for the 8 cathode wires running up to the 8 cathode layers.
Of course, you don't want to have your LED cube on a wood colored base. We didn't have any black paint lying around, but we did find a giant black magic marker! Staining the wood black with a magic marker worked surprisingly well! I think the one we used had a 10mm point. That sounds very easy, but it's not. You have to align 64 LED legs to slide through 64 holes at the same time. It's like threading a needle, times We found it easiest to start with one end, then gradually popping the legs into place.
Use a pen or something to poke at the LED legs that miss their holes. Once all 64 LED legs are poking through the base, carefully turn it on it's side. Then bend all 64 legs 90 degrees. This is enough to hold the cube firmly mounted to the base. No need for glue or anything else. All the wires are bent 90 degrees. This is more than enough to hold the cube in place. But you need to connect the ground layers too. Remember those 8 small holes you drilled in a previous step?
We are going to use them now. Make some straight wire using the method explained in a previous step. We start with ground for layer 0. Take a short piece of straight wire, Make a bend approximately 10mm from the end. Poke it through the hole for ground layer 0. Leave 10mm poking through the underside of the base. Position it so that the bend you made rests on the back wire of ground layer 0.
Now solder it in place. Layer 1 through 7 are a little trickier. We used a helping hand to hold the wire in place while soldering. Take a straight piece of wire and bend it 90 degrees 10mm from the end. Then cut it to length so that 10mm of wire will poke out through the underside of the base. Poke the wire through the hole and let the wire rest on the back wire of the layer you are connecting.
Clamp the helping hand onto the wire, then solder it in place. Rinse and repeat 7 more times. Carefully turn the cube on it's side and bend the 8 ground wires 90 degrees. Pre-tin the cables before soldering! Layer 2 3. Our 8 wire ribbon cable didn't have a red wire. Ground for layer 2 Image Notes 1. We didn't have the appropriate tool on hand.
The cathodes are connected with 4 wire ribbon cables. Just flip the connector degrees if your cube is upside-down. Layer 0 3. Layer 1 2. The ground layers use an 8-wire ribbon cable. Each of these ribbon cables are split in two at either end. Ground wire for layer 0 2. Layer 3 4. Ground for layer 1 3.
These plug into standard 0. We used ribbon cable to make things a little easier. Layer 0 Step At the controller side. The red stripe on the first wire indicates that this is bit 0. The metal inserts are supposed to be crimped on with a tool. We also added a little solder to make sure the wires didn't fall of with use. See pictures below. The header connector is a modular connector that comes in two parts. The connections are a bit flimsy. The cube will last a lot longer with this strain relief.
No room for resistors and connectors. Instead we decided to separate the latch array and power supply part of the circuit and place it on a separate board. The latch array took up almost all the space of the circuit board.
A ribbon cable transfers data lines between the two boards. Way to little space in between the ICs. Choosing two separate boards was a good decision. You may not have the exact same circuit boards as we do. There wouldn't have been much space for the micro controller and other parts.
This is better. Try to place all the components on your circuit board to see which layout best fits your circuit board. It soon became clear that cramming all the components onto one board wasn't a good solution. You may be thinking that this is an odd number to use. To get flawless serial communication.
As you can see all of these RS baud rates can be cleanly divided by our clock rate. We won't be running any error correcting algorithms on the serial communications. Serial communication will be error free! We want to be able to control the LED cube from a computer. This is the frequency of the system clock http: Serial communication requires precise timing.
If the timing is off. It was a bit hard to have the camera in the way when we were soldering. Probing the crystal Step You can see in the video how we do it. We had to touch some of the points twice to join them. Once you master this technique. Before you continue. This is what the clock signal from a crystal looks like Image Notes 1. I got an oscilloscope for Christmas: D we used it to visualize some of the signals in the LED cube. Let's start with the easiest part. It is common practice to have a large capacitor at the input pin of an LM and a smaller capacitor at it's output pin.
Why so many capacitors? The LED cube is going to be switching about mA on and off several hundred times per second. Power terminal and filtering capacitors The cube is complete. Many things contribute to this. By adding capacitors. We placed a uF capacitor just after the main power switch. To get 5 volts output from 14 volts input means that the LM has to drop 9 volts. The moment the mA load is switched on. Ours outputted something like 14 volts.
Instead we used an external 5V power source. Way to hot to touch!
This works as our main power buffer. No wires. Bottom side of power supply. Resistance in the wires leading to the power supply. When the mA load is switched on.
Large capacitors can supply larger currents for longer periods of time. The LM isn't a very sophisticated voltage regulator. The uF capacitor probably isn't necessary. But as you may already know.
Power supply Image Notes 1. The LM was later removed. After that. It wasn't able to supply the necessary current to run the cube at full brightness. We used this with a 12V wall wart. Even with the heat sink that you see in the picture. The excess energy is dispersed as heat. If we remember correctly. Note that the input side of the latch IC sockets haven't been soldered yet in this picture.
Do not get that one! Don't worry. A layer in the led cube is switched on. The outputs of the latches are arranged in order We opted to place the connectors as close to the ICs as possible.
Resistor soldered to IC 3. Resistor soldered to connector http: Input side not soldered yet. This was removed later. The resulting rise in current draw makes VCC fluctuate a little Step IC sockets. In the second picture. Our main design consideration here was to minimize soldering and wiring.
We squeezed it as tight as possible. In the first picture. On the output-side. We read somewhere that it is common engineering practice to place a nF capacitor next to every IC. At the top of the board. The two horizontal traces is the "main power bus". In the bottom right corner. In the first picture you can see some solder traces in place. We used different colors for different functions to better visualize how the circuit is built.
We tend to follow that principle. These are noise reduction capacitors. Large circuit boards like this one. Next to that. The tiny blue wires are Kynar wire. The tiny blue wires are connected to the same pin on every latch IC. Look how easy it is to see what is signal wires and what is power distribution!
The nF capacitors make sure that there is some current available right next to the IC in case there is a sudden drop in voltage. This is the 8 bit data bus. We love working with this type of wire. Below each row of resistors. No need for pre-tinning. The orange wire connected to the bus is the output enable OE line. Because it is so thin. Power rails and IC power Remember that protoboard soldering trick we showed you in a previous step?
We told you it would come in handy. We went a little overboard when making straight wire for the cube. This is a 30 or 32 AWG american wire gauge wire. If we had used thicker wire. We solder them as continuous solder lines. We also added a capacitor on the far end of the main power bus. Very tiny. Kynar wire is coated with tin. This is unlikely. When the current on the output pins are switched on and off.
From the connector at the top. This connects the latch board to the micro controller board. Debugging a circuit with noise issues can be very frustrating. Connect the ICs. For every latch IC 74HC On the right hand side of the connector.
We used that for the VCC line that runs under the resistors. In the first image.
The ATmega32 has 4 ports. The three blue wires running from the connector to the 74HC is the 3 bit binary input used to select which of the 8 outputs is pulled low.
We use these ports to drive the data bus of the latch array and layer select transistor array. We call this an address selector because it selects which one of the 8 bytes in the latch array we want to write data to. PORTA is connected to the data bus on the latch array.
If you look carefully at the connector. A group of 8 GPIO 8 bits. AVR board Braaaaainzz!!! This board is the brain of the LED cube. From each of the outputs on the 74HC Then connect the address lines and the 8 clock lines.
These will be used for a button and debug LED later. Just to the left of the ATmega. At this time. We had some more left over straight metal wire. On either side of the ATmega there is a nF filtering capacitor. This could possibly blow the programmer and even the USB port the programmer is connected to! The second image shows the underside. Each capacitor is connected to a pin on the crystal and GND. It has GND.
The pinout on this corresponds to the pinout on the other board. The smaller 10 pin connector to the left. When this is in place.
In the top left corner. Next to it. The blue wires are the address select lines for the 74HC and output enable OE for the latch array. The large 16 pin connector directly above the ATmega connects to the latch array board via a ribbon cable. In circuit serial programming header.
One 10uF and one nF. We posted a thread in the electronics section of the AVRFreaks. But the cube was still very dim. This transistor was rated at mA current. We bought some transistors rated for over mA. The general response was. Our first attempt at this was an epic fail. The emitters connected together. Pull up resistors. Layers didn't switch completely off when they were supposed to be off. This is the only option available to us using the parts we had on hand.
If you know what you are doing. Two and two resistors work together. But our solution is tried and tested and also does the trick! For each layer. This removed almost all the ghosting. The first thing we did was to add pull-up resistors to try to combat the ghosting. The base of each transistors was connected to it's own resistor.
This type of resistor is called a resistor network. The LED cube worked. They even had valid theories and stuff. Connect this solder trace to GND. NPN general purpose amplifier. The collectors connected together to GND.
This point was connected to VCC after this picture was taken. Needless to say. We don't remember the model number. It just has a bunch of resistors connected to a common pin. We ended up trying PNA. It was our only solution that didn't involve waiting for new parts to arrive in the mail. We soldered in all the transistors and turned the thing on again. Signal goes to two transistors. If you use LEDs with different colors. An internal pull-up resistor inside the ATmega is used to pull the pin high when the button is not pressed.
When the button is pressed. To find the appropriate resistor. If nothing happens, download GitHub Desktop and try again. If nothing happens, download Xcode and try again.
If nothing happens, download the GitHub extension for Visual Studio and try again. Figure 1. A demo of the LED Cube in action. Figure 2. Underlaying circuit of the LED Cube. Figure 3. Connections between power supply, Arduino, and circuit. Some time ago I stumbled upon a youtube video showcasing an awesome LED cube that displays animations in 3D. I was intrigued. I searched the internet for a tutorial and found a post on instructable.
Coincidentally, the author of the article is the same person who made the youtube video. This gave me the inspiration to make my own. There is a problem, though, that this tutorial requires too many components and some of which are difficult to find. I told myself, "There must be an easier way!
As a result, I came up with my own design using only a few common components. In fact, you might have most of the components for this project if you bought an Arduino Starter Kit or some similar kits. Of course, this design is not the safest, nor production quality, but it's intended to be that way.
This project, after all, is a DIY toy I made to fulfill my crave of making things. You can buy an LED Cube kit on eBay for about times cheaper than what it costs to make it this way. The only thing you'll learn from those kits, however, is how to solder and that's it.
The PCB has all the traces required. The micro-controller is pre-programmed and you don't even need to know anything about electronics to put it together.