We’re suckers for any project that’s nicely packaged, but an added bonus is when most of the components can be sourced cheaply and locally. Such is the case for this little laser light show, housed in electrical boxes from the local home center and built with stuff you probably have in your junk bin.
When we first came across [replayreb]’s write-up and saw that he used hard drives in its construction, we assumed he used head galvanometers to drive the mirrors. As it turns out, he used that approach in an earlier project, but this time around, the hard drive only donated its platters for use as low mass, first surface mirrors. And rather than driving the mirrors with galvos, he chose plain old brushed DC motors. These have the significant advantage of being cheap and a perfect fit for 3/4″ EMT set-screw connectors, designed to connect thin-wall conduit, also known as electromechanical tubing, to electrical boxes and panels. The motors are mounted to the back and side of the box so their axes are 90° from each other, and the mirrors are constrained by small cable ties and set at 45°. The motors are driven directly by the left and right channels of a small audio amp, wiggling enough to create a decent light show from the laser module.
We especially like the fact that these boxes are cheap enough that you can build three with different color lasers. In that case, an obvious next step would be bandpass filters to split the signal into bass, midrange, and treble for that retro-modern light organ effect. Or maybe figuring out what audio signals you’d need to make this box into a laser sky display would be a good idea too.
Continue reading “Little Laser Light Show is Cleverly Packaged, Cheap to Build”
There’s just something about wielding a laser pointer on a dark, foggy night. Watching the beam cut through the mist is fun – makes you feel a little Jedi-esque. If you can’t get enough of lasers and mist, you might want to check out this DIY “laser sky” effect projector.
The laser sky effect will probably remind you of other sci-fi movies – think of the “egg scene” from Alien. The effect is achieved by sweeping a laser beam in a plane through swirling smoke or mist. The laser highlights a cross section of the otherwise hidden air currents and makes for some trippy displays. The working principle of [Chris Guichet]’s projector is simplicity itself – an octagonal mirror spun by an old brushless fan motor and a laser pointer. But after a quick proof of concept build, he added the extras that took this from prototype to product. The little laser pointer was replaced with a 200mW laser module, the hexagonal mirror mount and case were 3D printed, and the mirrors were painstakingly aligned so the laser sweeps out a plane. An Arduino was added to control the motor and provide safety interlocks to make sure the laser fires only when the mirror is up to speed. The effect of the deep ruby red laser cutting through smoke is mesmerizing.
If laser sky is a little too one-dimensional for you, expand into two dimensions with this vector laser projector, and if monochrome isn’t your thing try an RGB vector projector.
Continue reading “A Laser Effect Projector Built with Safety in Mind”
Redditor [ squishy0eye] lacked a coffee table and wanted an infinity mirror. So, in a keen combination of the two, she built an infinity mirror table the resembles a nighttime cityscape.
Skimming over many of table’s build details, [squishy0eye] paused to inform the reader that an MDF base was used underneath the mirrors, with a hole drilled for the future power cable. For the top pane, she overlaid privacy screen mirror film onto tempered glass, turning it into a one-way mirror. The bottom pane is acrylic plastic due to the need to drill holes to hide the cables for each ‘building’ — the same mirror film was applied here as well. Wood was cut into rectangles for the building shapes and super glued around the holes and in the corresponding spots underneath to prevent any bowing in the acrylic. A small gap was left in each ‘building’ to run the 5050 non-waterproof LED strips around and back into the hole for power.
Continue reading “Cityscape Infinity Table”
[Nathan] wanted a smart mirror that cost less than the last one he built, which was about $500. He decided that you don’t see more smart mirrors because of the high cost. His latest build came in at only $79 (you’ll have to visit the blog’s home page to find the entire series).
The most expensive piece of the build is a 7-inch monitor ($45). Any Raspberry Pi will work, although [Nathan] uses a Pi B+. Although he managed to score a free one-way mirror from a local glass shop, you can buy one for about $13.
This is the kind of project that isn’t a big technical challenge. After all, it is a one-way mirror with an LCD screen behind it. However, getting the screen blacked out and set to provide the best possible effect is the trick and [Nathan’s] techniques will give you a head start.
You can see the mirror in the video below. We’ve seen smart mirrors that sense your presence as well as wireless mirrors before.
Continue reading “$79 Smart Mirror Uses Raspberry Pi”
We all have different ways of expressing excitement about new family members. [viscomjim] expressed his joy at the arrival of his first grandchild by building a twitter-enabled mirror/mood light. While we’d like to rage that this Internet of Things “thing” that people are doing has gone too far, this isn’t the first time we’ve seen this happen.
For the brains of his device [viscomjim] used an ESP8266 module. [Viscomjim] etched his grandchild’s name into the mirror and put some Neopixels behind it. When one of his family members tweets to the light’s channel they can change the color of the light to interact with their newest family member. We’re not so certain the Internet won’t find this and turn it into baby’s first 24 hour rave.
If you’d like to get in on the ESP8266 action, you’ll find the Huzzah board a good start, and we’ve got a special Hackaday edition in the store. Just sayin’.
What Parisian wouldn’t want an apartment with a view of the Eiffel Tower? Alas, not every window can face the famed landmark, and for some, the million Euro view is tantalizingly out of reach. Such was the case for [Lurluberlu], but with a little optical trickery he was able to peer around a corner to deliver spectacular views of the Eiffel Tower to his bedroom.
[Lurluberlu] devised a simple horizontal periscope using two full-length mirrors. The video after the break shows the build – as a side note, we’re very jealous of his hand tool packed workshop. With some plywood backing and simple swivels, the mirrors were mounted on his window sill to bounce the iconic tower’s image inside. After a little adjustment, the image is perfectly framed by the window, and with the lights off in the apartment, the view from the bed is quite spectacular. Our bet is that it’s quite a bit cheaper than moving to a flat with a better view.
Of course, with a little ingenuity (and a balcony) anyone can have a view of the City of Light. Or anywhere else for that matter.
Continue reading “Spectacular View of the Eiffel Tower is all Done With Mirrors”
Mirror galvanometers were originally developed in the 17th century to precisely measure very small changes in current. Unlike other instruments of the day, a mirror galvanometer could clearly show minute current variations by translating tiny movements of the mirror into large movements of the light reflected off of the mirror. Before clean electrical amplification became possible, this was the best means of measuring tiny differences in current. True mirror galvanometers are very sensitive instruments, but hobby servos can be used as a low-fidelity alternative, like with this project on Hackaday.io created by [robives].
Using a mirror galvanometer is by far the most common technique for laser projection shows – it’s really the only way to move the laser’s beam quickly enough to create the visual illusion of a solid line in real time. A mirror galvanometer works by using coils to attract magnets attached to the mirror, allowing the angle of the mirror to change when current is applied to the coils. This movement is extremely small, but is amplified by the distance to the projection surface, meaning the laser’s beam can move huge distances in an instance. If you’ve ever seen a laser show, it almost certainly used this technique. But driving galvos requires a beefy DAC, so we can’t blame [robives] for wanting to keep it digital.
[robives’s] project side-steps the need for galvanometers by using glow-in-the-dark vinyl and a UV laser. The result is a laser beam trail which lasts much longer, which means that solid lines are visible without the need for high-speed galvos. A build like this lets you experiment with laser projections without dealing with sensitive mirror galvos, and instead use components that you probably already have sitting on your workbench.
Continue reading “UV Laser Projector Shines With Glow-in-the-Dark Vinyl”