No matter how good the intentions or how strong your hack-fu may be, sometimes you just can’t cross the finish line with every project. Here’s one that we hate to see go unfinished, but it’s obvious that a ton of work already went into reclaiming these smart white-board projectors and it’s time to cut the losses.

The hardware is a Smartboard Unifi 35″ computer with a projector mounted on a telescoping rod. It was manufactured for use with a touch-sensitive white board which the guys at the Milwaukee Makerspace don’t have. The projector works, but all it will display is a message instructing the user to connect the computer to the white board. Since they’ve got a couple of these projectors, it would be nice to salvage the functionality.

The first attempt was to replace the video signal to the projector. A few test boards were etched to experiment with DVI input. This included several logic sniffing runs to see what the computer is pushing to get the warning message to display. Alas, the group was not able to get the device to respond. But this opens up a great opportunity for you to play Monday morning hacker. Take a look at the data they’ve posted in the link above and let us know how you would’ve done it in the comments.

Back in 2001, [Helmar] made an awesome monochrome video display out of a red laser pointer and a spinning 18-sided mirror. Blue and green lasers are much less expensive than they were a decade ago, so [Helmar] decided to go full color with his laser projector. (In German, so fire up Chrome or get the Google translation)

The ancient website for [Helmar]‘s green-only projector goes over the principles of operation. A single laser shines onto a multi-faceted polygonal mirror. This is reflected onto another mirror that provides the reflection for each line in a frame of video. Earlier this year, [Helmar] hacked up a red and blue laser to complement the preexisting green laser. The end result is an RGB projector powered by friggin’ lasers.

As far as we can tell, the projector only has composite input; the attached DVD player provides all the signaling for that. Amazingly, [Helmar] didn’t use a microcontroller for the circuitry. All the electronics are simple logic gates. Really amazing if you ask us.

This wire-frame cube appears to be floating in mid-air because it actually is. This is a project which [Tom] calls a Laminar Flow Fog Screen. He built a device that puts out a faint amount of fog, which the intense light from a projector is able to illuminate. The real trick here is to get a uniformed fog wall, which is where the laminar part comes in. Laminar Flow is a phenomenon where fluids flow in a perfectly parallel stream, not allowing errant portions to introduce turbulence. This is a favorite trick with water.

[Tom's] fog screen starts off with a PC fan to move the air. This airflow is smoothed and guided by a combination of a sponge, and multiple drinking straws. This apparatus is responsible for establishing the laminar flow, as the air picks up fog from an ultrasonic fogger along the way.

The only real problem here is that you want the projector shooting off into infinity. Otherwise, the projection goes right through the fog and displays on the wall, ruining the effect. Outdoor applications are great for this, as long as there’s no air movement to mess with your carefully established fog screen.

You can find a short test clip embedded after the break but there are other videos at the link above.

We can think of no better way to describe this laser projector project than Epic. [C4r0] is a student at Gdansk University of Technology and he’s been working on this projector for at least a couple of years. It uses several different laser diodes pulled out of DVD burners, Blu-Ray drives, and entertainment equipment (the green diode is from a disco laser).

In order to direct the beams he built a series of brackets that hold dichroic filters which reflect some wavelengths of light while allowing others to pass straight through. Each diode also needs a driver, most of which he built from scratch. And once the hardware has been designed and tested, what does one do with it? If you’re [C4r0] you build it into a money case with professional-looking results.

Don’t miss the video demo after the break. And make sure you have a rag ready to wipe up the drool before you look at his forum post linked above.

[Thanks Kodex]

Who hasn’t thought about turning a 1950s slide projector into a digital projector? [Matt] did, but unlike most of us, he actually did it.

[Matt]‘s friend [Angus] found an old, single-slide, sans-carousel slide projector in the trash. It’s a wonderful piece of ancient technology with a fabric insulated power cord and bakelite lamp socket. This projector was upcycled to the 21st century by adding a 10 Watt LED and a Nokia 1200 LCD.

For the electronics, [Matt] used an ATmega88 microcontroller. There’s an infrared receiver so the remote from an in-car CD player can be used to advance the slides and turn the projector on and off. The LCD is controlled by a bit of bit-banging from the Mega88, using hard-coded images of Che Guevara, Hendrix, Space Invaders and some old-school Macintosh/Lisa icons. Unlike the screen printed t-shirts at American Apparel, Che is the only authentic image in this project; this projector might have been made after Guevara came to prominence.

With a 10 Watt LED, it’s not the brightest projector on the planet and the picture is a little washed out in a bright room. With dim lighting, it’s a very good project even if the images are static.

This hack is not for photographers with weak hearts. We’re going to be talking about destroying the body of a Single-Lens Reflex camera. But out of destruction comes something new. A broken camera paired with a flash and functional optics can be used to project light patterns for picture backgrounds.

The hardware is often referred to as a cookie projector, and a commercial unit can cost several hundred dollars. But if you or someone you know has a non-functional film SLR you’re already half way to making your own. Just snap off the back cover, yank out the mirror and shutter, and the bloody part is over. Slap on a lens with a large aperture, create your own slide with the pattern you’d like to see in your images, and affix a flash to the gaping hole on the back of the camera body. The video after the break shows the diy cookie projector hanging out on the flash stand, synchronized with your DSLR flash to add some pizzazz to the photo shoot.

It always blows our mind to see the things that people dream up when playing with Lego. Given enough time, you could likely replicate almost any mechanical device with the right amount and type of blocks.

[Friedemann Wachsmuth] recently wrapped up construction on a very impressive Super-8 movie projector with the help of his friend [Kalle]. The projector is fully functional, and is made completely from Lego aside from the reel spindles, the lens, and the lamp. As you can see in the video below the projector plays the film quite well, and even though it is only lit using an LED flashlight, it’s more than bright enough to get the job done.

The projector boasts automatic film feeding, a 24 fps framerate, as well as fast rewind capabilities – all provided by just two small Lego Technic motors.

You really need to watch the video to appreciate how much work went into this projector – it’s amazing.

[via RetroThing]

A few common components come together to make this interactive museum exhibit that teaches about the sun (translated). It uses three main physical components to pull this off. The first is a custom projection surface. It’s a hemisphere of the sun with a slice cut out of it. This is presumably coated with the paint you’d use to turn a wall into a projection surface. Software translates a projected image to map correctly on the topographic surface, resulting in what you see above, with a Kinect for user input.

Take a look at the video embedded after the break to see how the exhibit works. It instructs patrons to stand on a pair of footprint markers on the floor. This positions them at the proper range from a Kinect depth camera, which translates their outline into cursor commands. By moving a hand around they can explore the different parts of the sun.

We’re in love with how easy this type of interaction is becoming. Granted, there’s a fair amount of work that goes into to the coding for the project, but the physical build is quick and relatively inexpensive.

[Thanks Lukasz]

Twitter can be a great tool for keeping up to date with your favorite person/company/band/etc. You can find a Twitter client for just about anything that plugs in these days, but sometimes we find that we simply need a break from our computers and smart phones – even if just for a few minutes. What happens when you want to unplug, but still need to know what everyone is up to?

[Patrick Dinnen] asked himself the same thing, and decided that the solution was a mechanical Twitter feed display. The display consists of a static user list strung up against the wall, with a mobile speech bubble mounted next to it. The bubble moves to the user who has most recently updated their status (presumably using a pair of servos), and uses a projector to display their messages. The effect is pretty neat, and it still allows you to get your Twitter fix without staring blankly at your computer screen or smart phone.

We think it would be even cooler if it used a projector on both sides, enabling it to dynamically shuffle through users and status messages at the same time. [Patrick] says that for right now it is merely a proof of concept, so there is no telling how he’ll tweak it going forward.

Continue reading to see his mechanical Twitter feed in action.

[via Adafruit]

Augmented reality might be all the rage these days, but when you take a closer look at the technology, you will find that these sorts of optical illusions are not new at all.

Artist [Sebastian Schmieg] was pondering augmented reality for a bit and decided he could replicate the effect using old and obsolete technology. His creation, called “81 Points of View”, uses an old Kodak slide projector and an elaborate mechanical setup to simulate the effect.

The slide projector resides on a platform that can be rotated around its center in 81 steps. After each movement, the mechanism swaps out the current slide, selecting the next image depending on which direction the user turns. The resulting effect is similar to the implementations of augmented reality you might see today, with a 3d visualization superimposed on the surrounding room.

The concept dates back all the way to the 1860′s, when [John Pepper] first demonstrated the technique. Using mirrors and panes of glass, he was able to project translucent images in front of his audience, which is the same idea [Sebastian] uses in his project. You are likely quite familiar with the effect, if you have ever visited the Haunted Mansion at a Disney theme park.

It’s a neat project, though the resultant augmented reality display is obviously not quite as smooth as you would see from a smartphone. Either way, it is definitely worth checking out. Keep reading to see a video of the project in action.

[Devon] recently repaired a handful of Phillips LCD projectors which he was quite excited to use. The only problem is that he didn’t want to mess with replacing the bulbs after every 2000 hours of use at $100 apiece. He was pretty confident that he could find a better way to drive the projectors, so he disassembled them once more and started looking around for bulb replacements.

He figured that a high-powered LED would do the trick, so he ordered a handful of parts and went about his first retrofit. Using his oscilloscope, he found that the control board pulses the high voltage board when the projector is powered on, and continues to pulse a signal until the machine is turned off. At this point, the HV board powers down the bulb.

He created a small circuit using a PIC that is used to interpret the initial pulse from the control board as well as watch for the steady “heartbeat” pulses that occur while the projector is powered on. This board is used to control the driver board for the high-powered LED he purchased.

His bulb replacement works well as far as color fidelity is concerned, but is not nearly as bright as he hoped for. He has plans to source some far brighter LEDs or automobile HID lighting in the very near future, and we look forward to seeing if he can match the brightness of the original bulbs.

[Jose Carlos Veloso Junior] has been working on his 3D printer to improve the resolution. We looked in on his project back in October when he was printing the blue busts like the one seen above.

We were impressed by the resolution he was able to achieve back then, using liquid resin that is cured with visible light. The resin creates a thin layer on a glass tray, and is cured when a projector shines precisely positioned light from below. The cured resin is then lifted on the Z-axis, and the next layer in the printing process is hardened by the projector’s light.

Well, this newest rendition far outperforms the initial iteration. The bust on the right looks like it’s been hand-buffed to remove the layer lines, but it actually just came off of the printer. [Jose] made a video of the new equipment in action, which you can watch after the break. He’s keeping most of the juicy bits to himself but he did tell us that the improvement he achieved were due to multiple changes in the process. He tweaked the software to use a more precise curing time, the resin formula has been improved, the ability to isolate pixels without hardening resin around them has been stepped up, and he’s made changes to the way the printer is calibrated and how it lifts the hardened model.

This is fantastic. Kudos to you sir!

[Jon Howell] came up with what he calls a gratuitous project which projects his name on his office door. The thing is, his office door slides on tracks so he made a projector that can follow the movement of that screen. He used a laser printer to make a black and white pattern that indexes the movement of the door using a quadrature encoder. When it senses door movement a servo motor rotates the projector to match the change in the door’s location. As you can see in the video after the break it works even if the door is moved quickly.

We do agree with [Jon], this is a bit much. But it might be something to build into smart white boards that are mounted on sliding tracks. We guess that if you don’t plan to change the message being projected, which is the case with [Jon's] office door nameplate, this would be a great way to use the image projector build we looked at yesterday.

[yotuube=http://www.youtube.com/watch?v=EA_CLhGWAw4]

There’s a pretty good chance that you already have everything needed to make this image projector. We thought that yesterday’s video projector was simple, but this one makes it look like a super-computer in comparison. [Esrun] grabbed a flood light, some transparency film, and a common magnifying glass for use in his still-image project. This is more-or-less an overhead projector without the mirror, but we though it was worth sharing in hopes that it would spark your imagination and produce some other projector-oriented hacks.

The real tricks in this build are alignment and focal length. A single piece of lumber was used to help keep everything in a straight line, leaving just the vertical alignment to account for. In order to get the image in focus, [Esrun] had to do some testing for positioning the transparency film and the lens. In the end he added strips of velcro to the base to make the components easy to move. He plans to add an enclosure and change from an incandescent bulb over to a set of LEDs. We’d like to see the addition of a carousel that can house multiple transparency sheets. That or a side-scrolling roll to give it more of a film-strip feel.

Here’s a video projector that [Matt] hacked together. He needed a small and inexpensive solution to use with his R2D2 build. As you can see in the video after the break, it has no problem playing back the Princess’ distress call. But even if R2D2 is not one of the droids you’re looking for, we think this can be useful in other ways. One use that pops into mind is for projector-based Halloween displays.

As with past projector hacks, all you really need to pull this off is a light source, an LCD screen on which you can playback video, and a lens to focus the light onto a screen. Usually the LCD is the most expensive part of the project and building an enclosure to the correct dimensions can be a bit difficult. [Matt's] solution was to use an MP4 knockoff media player. The rest of the setup is a ’50s era slide projector. The screen from the media player is about the same size as a single film slide, so he removed the screen from the case and put it where the slides go.