Supreme job! I am at your mercy. [\bow down and kissing your feet mode\] Question: What does the C transistor do? I understand how A and B work, but what is the function of C? Question: How do you intend to control the LEDs (above the PIC)? Are you planning an PC interface? Question: What is the power requirement for 1000 LEDs? A birt off topic, but what do you think is the minimum gage wire for running a project like this; assuming 1000 LEDs? To your question, I used a gif animator a few years ago that was freeware and had timing contorls. Let me dig around and find it for you.
Always nice to know that one's efforts are appreciated. Question: What does the C transistor do? I understand how A and B work, but what is the function of C? Answer: The A and B are for the 2D matrix. Adding several 2D matrixes, sort of "on top" of each other, makes the 3D cube. The C controls each 2D matrix. See also answer about power requirement. Question: How do you intend to control the LEDs (above the PIC)? Are you planning an PC interface? Answer: Well, as the whole thing is being designed to operate from an 8 bit data bus, with 2-4 control bits, it could be, in principle atleast, controlled from the parallel port of a pc. I do however plan to make also make it uC controlled. At least for updating the LEDs. For simple operations like 3D sound equalizer a uC could also be used to genetate the 3D image to be shown, but otherwise a PC program should probably be used to generate the 3D images for the cube. I am however not much of a PC programmer, so I'll probably just end up with a version 1 of a LED cube that can control the LEDs but not necessarily show/generate very advanced images. And then hope someone else might have an interest to create some kind of imageing program for it. Question: What is the power requirement for 1000 LEDs? Answer: Well, as we ever only light up ONE row of LEDS (= max. 10 LEDs) the max. power consumption should not be more than 1 Amp. Normaly a LED will need/use 20mA, or it will overheat, and as we only light up at the most 10 LEDs at a time, that would add up to 200mA However, as each LED is only lit for a very short time (typically <1mS at a time) we can increase the power burst to something like 90-100mA per LED. With a max of 10 LEDs being on at a time then the max power consumption will be 1Amp + something like 100mA for all of the control logic and the uC If we were to exceed the 1Amp mark for one row of LEDs, we would also need more powerfull B and C transistors, than the BC639, as it has a max of 1 Amp. Q: A bit off topic, but what do you think is the minimum gage wire for running a project like this; assuming 1000 LEDs? A: With a typical use of only 1 Amp for the whole Cube, the supply wire for the project should not need to be very big at all. All power will be run on the LED board. I use this referance chart to ensure that PCB wires are thick enough. The control wires for the Control connectors named PortA, PortB and PortC on the LED board, can be any thickness (or thinness, I suppose) as the control wires will typically only use 2-5mA per wire. That would be great.
D4mn you all! Now I'm going to have to spend a bunch of money to build one of these things. www.allelectronics.com has $ .07 leds, albeit in red. 125 LED (5x5x5 matrix should be only $ 8.75 However, i don't want to go all out for a big 10x10x10 withouth experimenting. I have already messed around with 2d led matrixes, mostly in hope of building a solid state oscilloscope, with the help of a lm3916 in combination with a simple sweep generator. I'm still working on a system for triggering though. This thread has got me interested again, though.
I think your schematic is great, but the drawback is, that you can't drive more than 10 leds at a time, and that is not much, even at 100 ma/led that is 1 ma because of the refreshing time. I think I'm going to drive a 100 leds at a time and a variable power supply so you can control the brightness of the leds. I am also working on a control program in visual basic, and waiting for the parts to arrive. I will post the pcb I build quickly, but I need to finish it first and gotta work tomorrow :S, For the PIC users in this community, I'm going to use a 16f877a for controlling the data flow from the parallel port and it is also able to store 2 pictures in his memory, so it will always be able to show them, even without a computer. I also have an old keypad with 5x11 buttons, so you can also make your own outputs without a computer. Maybe some more memory is going to be installed in my schematic, so I can also store images on a eeprom chip. Ow, there are some pictures of my 3x3x3 cube on the internet, here:
cheapest LEDs I can find so far! Ive been thinking about making one of these. Anyway for cube designs, I think itd be nicer if you used a cheet of clear accrylic or something between each layer so that they all lineup nicely. Might have problems with the LEDs lighting up the accrylic though.. Itd be better If you could use SMD leds with very very fine wire, but I dont think thats really practicle to do... Anyway, so far, rapid are the cheapest Ive found, £25 for 1000 in red, or £28 for yellow/green, HERE If 10 people wanted to do this, £18 each is all itd cost for the leds, thats cheap.
I already got my leds for 18 euro/ 1000 leds (red) I also think that lining the leds up will be one hell of a problem, first you need really straight pieces of solid wire of about 40 cm each but then, if you want to solder them it will be a very nasty work, because it doesn't matter how you do it, it is very hard to gain acces to places inside the cubicle :S
Thats cheap, what company was that from? To assembele it,itd be best to do it layer by layer. The leds on the middle of each layer would be hardest, so it might be best to use very thin single core wire (so its not so visible), and bring it past the led a tiny bit, instead of having the connection between the two leds. To line them up, today I had the idea of using a clear plastic frame, which would go between the legs of each led, to form one big grid.. it would help strengthen it too.. so that thinner wire could be used without making it weak... I dont know how well it would work, but plastics go brittle if you freeze them (at -40 ) so you could use some thick'ish fishing line (15-30lb?) and freeze it to make a cheap but strong frame..
Yes, you may be right. If I am to build one of these thingys, a few test may very well be in order, before committing to any one design. About Lineing up the LEDs One may be able to make a template, say from a block of wood, and drill 10 x 10 holes. Then insert the leds head first. Solder whatever wires one wants. This would only be in the X,Y directions whild the LEDs are in the wooden template. When done, then lift the 2D matrix out of the wooden template. Then all LEDs would be alligned perfectly, and the wires would be somewhat straight, but still have the personality of "handmade" design. To make sure the LEDs would eaisly come out of the wooden template, the holes probably need to be 6mm for 5mm LEDs. One would then stack the 2D "pancakes" on a LED pcb or some other base. To strengthen the 2D layers, in effect have them support one another, one could glue acrylic rods in the Z direction. It would probably only be necessary to do the two outmost LEDs on either side (like 1,2 and 9,10) to make the support strong enough to be able to transport the cube, without it collapsing. Looking forward to seeing some pictures of your design.
To make the cube look the best, the 100 iron wires across the y-axis will each be connected to 10 leds, so 10 layers will be made, that's the way with the least extra wires going through the design, only 10 more, 1 for each layer, the drawback of this design is that you can't first make the 2d layers :S, the solution to this problem is, while soldering the cube, put the cube on 1 side and then solder the leds. I'm sorry but my drawing skills suck, so I can't explain very clearly. The positive side of this way of constructing, is that it will be very strong, and doesn't need extra support, because you already have a 100 wires as support. And when I come to think of it, it wouldn't be so hard after all this way, only a lot of work The leds can arrive any minute now, so I will begin constructing fast. The electronics to drive the circuit have to wait. At school I have tried a few things with a oscilloscope and I found out that the mosfets + driving circuit I want to use are fast enough, as long as the power supply is stable, powering everything won't be that difficult. Ps, I ordered the leds through a 1-time action, so you might need to search for another supplyer, I'm sorry I also noticed that a calculation on this thread is wrong, if you want a 100 hertz refresh rate, then you need 1000/8 = 125 125*100= 12500 byte's/s 12500/1024= ca 12,5 kb/s which shouldn't be a problem for a parallel passthrough, the only problem is, that you need a decoding algorithm, because the parallel port data must be converted to the data for the cube, which will be transferred serially, but with a bit of programming, that shall be do able
The leds have arrived a week ago and now I have started constructing the cube. First, I tested al the leds to see if there were any wrong leds between the 1100 leds I ordered, I found 3. After that a friend of my and I started bending al the led legs in the right position and cutting them at the right length: After the hacking and slicing, I took a plate of wood and printed a grid on it of 10x10, with spaces of 4 cm between 2 lines, so the leds will be 4 cm apart. Then I took some nails and hammered them into the wooden plate to guide the 0,7 mm iron wire: The iron wire comes in after this, you roll the end of the wire to one of the nails in the corner and then you guide the wire along all the other nails, very tight and attach to the last nail. You then have all the vertical wires. The constructing after that is quite easy, you solder the leds with the negative leg to the vertical wires: after you have done that with a 100 leds, you make some new iron wires to solder horizontally to the positive leg of the led: Then you slowly get it off of the plate and then you can construct another one. I have finished 3 of the 10 layers when I wrote this text. I work 1,5 hour on one layer. I also promised to post the layout of the circuit board here, but I made a mistake, so I had to start over again, after 3 hours of work P.s. I hope all the pictures work. They worked here, but not very fast, but that might be my connection or the server, I dunno
LED supplier Can you let us know where you obtained those LEDs. Sounds a good deal. Just putting my layers together. Will let you know how they work out.
i think i might have found where our little dude bought the leds but its in dutch though its a web site where together they buy big quantities of stuff so the price is low cool huh http://inkoopactie.net/ia/q75gc8k5/1?g=kzchn7cp
C'mon man - I want to see more ! .. oh. Hows did you pull that wire-frame through? As far as I know, iron is quite conductive. Did you strip and add another piece of lead for each led?
alright, here is the led cube in its full state. working on the software right now, I can already make some pictures appear on the cube. The used PCB: More pictures will follow when the cube is in full working order P.s. The iron wires are the wires that guide the electricity to the leds, only 10 extra wires where added, one for each layer. But I don't think you can spot them, because they're made of isolated copper wire and are hard to see
Dear God! That looks better than the artists origional one! You say you have also made the controller and have it WORKING! you work fast mate... Very fast and very nice...
I've thought about doing somthing like this for a while, but I was planning on using multiplexers and decoders similar to a really basic memory controller. The image would be rastered a bit like TV. If it was 8x8x8 at 30 frames per second, the clock is about 15.4KHz, easily doable with the logic that is out there, and even most cicrocontrollers would run it fine. Finding decoders and multiplexers that can drive the LEDs shouldn't be too hard, but if not, the driver circuitry is not very complex. Other fancy stuff like latches and transcievers can flesh the design out later.
why? because blue leds are ca 0,1 euro/s 0,1 * 1000 = 100 euro now I have 1000 leds for 18 euro And blue leds would be to bright, one would light the whole cube.
