[dmitry] writes in to let us know about a new project that combines lasers with fans and turns the resulting modulation of the light beams into an autonomous soundscape. The piece is called “divider” and is a large, wall-mounted set of rails upon which seven red lasers are mounted on one end with seven matching light sensors mounted on the other end. Interrupting the lasers’ paths are forty-two brushless fans. Four Arduino Megas control the unit.
Laser beams shining into light sensors don’t do much of anything on their own, but when spinning fan blades interrupt each laser beam it modulates the solid beams and turns the readings of the sensors on the far end into a changing electrical signal which can be played as sound. Light being modulated by fan blades to create sound is the operating principle behind a Fan Synth, which we’ve discussed before as being a kind of siren (or you can go direct to that article’s fan synth demo video to hear what kind of sounds are possible from such a system.)
This project takes this entire concept of a fan synth further by not only increasing the number of lasers and fans, but by tying it all together into an autonomous system. The lasers are interrupted repeatedly and constantly, but never simultaneously. Listen to and watch it in action in the video below.
If you’ve had a child in the last few decades, you’ve had a choice to make: if you want to know the sex of the baby ahead of time. With ultrasound you can find out or–popular these days–you can have the result sealed and have a baker create a reveal cake. Apparently, researchers at the Dresden University of Technology and the University of Leipzig wanted to do the same trick with unborn chickens.
You might wonder why anyone cares (we did). Apparently, chickens that are bred for egg laying don’t produce roosters suitable for food use. This leads to about half of the chicks being “culled” (a less ugly euphemism than gassed or shredded) and used in–among other things–animal feed. Worldwide, billions of chicks are culled each year and that’s not counting other similar situations like male turkeys and female ducks.
Experimenting with optics can be great fun and educational. Trouble is, a lot of optical components are expensive. And other support paraphernalia such as optical benches, breadboards, and rails add to the cost. [Peter Walsh] and his team are working on designing a range of low-cost, easy to build, laser cut optics bench components. These are designed to be built using commonly available materials and tools and can be used as low-cost teaching tools for high-schools, home experimenters and hacker spaces.
They have designed several types of holders for mounting parts such as lasers, lenses, slits, glass slides, cuvettes and mirrors. The holder parts are cut from ¼ inch acrylic and designed to snap fit together, making assembly easy. The holders consist of two parts. One is a circular disk with three embedded neodymium magnets, which holds the optical part. The other is the base which has three adjustment screws which let you align the optical part. The magnets allow the circular disk to snap on to the screws on the base.
A scope for improvement here would be to use ball plunger screws instead of the regular ones. The point contact between the spherical ball at the end of the screw and the magnet can offer improved alignment. A heavy, solid table with a ferrous surface such as a thick sheet of steel can be used as a bench / breadboard. Laser cut alignment rods, with embedded magnets let you set up the various parts for your experiment. There’s a Wiki where they will be documenting the various experiments that can be performed with this set. And the source files for building the parts are available from the GitHub repository.
Check out the two videos below to see how the system works.
Wafer level chips are cheap and very tiny, but as [Kevin Darrah] shows, vulnerable to bright light without the protective plastic casings standard on other chip packages.
We covered a similar phenomenon when the Raspberry Pi 2 came out. A user was taking photos of his Pi to document a project. Whenever his camera flash went off, it would reset the board.
[Kevin] got a new Arduino 101 board into his lab. The board has a processor from Intel, an accelerometer, and Bluetooth Low Energy out of the box while staying within the same relative price bracket as the Atmel versions. He was admiring the board, when he noticed that one of the components glittered under the light. Curious, he pulled open the schematic for the board, and found that it was the chip that switched power between the barrel jack and the USB. Not only that, it was a wafer level package.
So, he got out his camera and a laser. Sure enough, both would cause the power to drop off for as long as the package was exposed to the strong light. The Raspberry Pi foundation later wrote about this phenomenon in more detail. They say it won’t affect normal use, but if you’re going to expose your device to high energy light, simply put it inside a case or cover the chip with tape, Sugru, or a non-conductive paint to shield it.
Seb Lee-Delisle has built a career around large installations that use powerful lasers and high-end projects to make people happy. It’s a dream job that came to fruition through his multi-discipline skill set, his charismatic energy, and a mindset that drives him to see how he can push the boundaries of what is possible through live interaction.
His talk at the Hackaday | Belgrade conference is about his Laser Light Synth project, but we’re glad he also takes a detour into some of the other installations he’s built. The synth itself involves some very interesting iterative design to end up with a capacitive touch audio keyboard that is lit with addressable LEDs. It controls a laser that projects shapes and images to go along with the music, which sounds great no matter who is at the keyboard thanks to some very creative coding. As the talk unfolds we also hear about his PixelPyros which is essentially a crowd-controlled laser fireworks show.
See his talk below and join us after the break for a few extra details.
There is a family of old photographic chemistries based on iron compounds which, like the blueprint, are exposed using UV light. Ironically, the digital camera revolution which has made everything else in our photographic lives much easier, has made it harder to experiment around with these alternative methods. [David Brown] is making a UV photographic printer to change that.
[David]’s application has a lot in common with PCB printers that use a UV-sensitive resist, only [David] needs greyscale, and it might also be nice if it could work with wet paper. This makes it a more challenging project than you might think, but we like the cut of [David]’s jib.
Like some of the other UV exposer projects, [David]’s uses a rotating mirror to scan across the to-be photograph’s surface. Unlike the other ones that we’ve seen, the exposer hangs from two linear rails. Other printers move the paper underneath a stationary scanning head, which seems a mechanically simpler arrangement. We’re excited to see how this goes.
When Jeffrey Brian “JB” Straubel built his first electric car in 2000, a modified 1984 Porsche 944, powered by two beefy DC motors, he did it mostly for fun and out of his own curiosity for power electronics. At that time, “EV” was already a hype among tinkerers and makers, but Straubel certainly pushed the concept to the limit. He designed his own charger, motor controller, and cooling system, capable of an estimated 288 kW (368 hp) peak power output. 20 lead-acid batteries were connected in series to power the 240 V drive train. With a 30-40 mile range the build was not only road capable but also set a world record for EV drag racing.
The project was never meant to change the world, but with Tesla Motors, which Straubel co-founded only a few years later, the old Porsche 944 may have mattered way more than originally intended. The explosive growth between 2000 and 2010 in the laptop computer market has brought forth performance and affordable energy storage technology and made it available to other applications, such as traction batteries. However, why did energy storage have to take the detour through a bazillion laptop computers until it arrived at electro mobility?
You certainly won’t find that grail of engineering by just trying hard. Rather than feverishly hunting down the next big thing or that fix for the world’s big problems, we sometimes need to remind ourselves that even a small improvement, a new approach or just a fun build may be just the right ‘next step’. We may eventually build all the things and solve all the problems, but looking at the past, we tend to not do so by force. We are much better at evolving our ideas continuously over time. And each step on the way still matters. Let’s dig a bit deeper into this concept and see where it takes us.