While the Hackaday reader likely knows all about Nikola Tesla and his incredible body of work, the same can’t necessarily be said for the average passerby. Even a child can be counted on to know the names of Thomas Edison and Alexander Graham Bell, but as [Daniel Springwald] laments, the name Tesla is more often associated with the line of sleek electric cars than the brilliant Serbian inventor they were named for.

Hoping to level the playing field a bit, [Daniel] has come up with a way for the great man to plead his case. This custom designed robotic facsimile of the alternating current aficionado is able to speak about Tesla’s life and accomplishments in an interactive, if rather creepy, format.

There isn’t a lot of technical detail on this one yet, but what we can glean from the image gallery and video below is that there are an incredible number of OpenSCAD-designed 3D printed parts knocking around inside Mr. Tesla’s head. Add into the mix a healthy dose of springs, linkages, and servos, and you’re just a mustache short of a museum exhibit.

Most of the animatronic projects we’ve covered in the past have been based on animals, so it’s certainly interesting to see what goes into approximating human mannerisms mechanically. We’re not sure if this talking Tesla head will help educate the masses, but it’s certainly an impressive technical achievement.

source https://hackaday.com/2020/07/08/animatronic-nikola-tesla-sets-the-record-straight/

If you have ever studied the early history  of the GNU/Linux operating system in its many forms, you’ll have read that [Linus Torvalds] developed his first kernel for his Intel 386-based computer. Though the 386 architecture is now ancient, the current Linux kernel can still be compiled for it and many distributions still maintain an i386 branch to provide broad compatibility for later machines able to run i386 code. But what if you were to take a current Linux kernel and stick it on a floppy in a machine from the early 1990s, with meagre RAM? [Fozztex] did just that, with not a 386 but a 486, sporting what would have been an impressive for the time 36MB of RAM. You can watch it in action in the video below the break.

A recent Linux kernel is rarely if ever compiled for something as small as a floppy disk, so getting one to boot from such ancient media appeared to be a challenge. It was possible though with the tinyconfig make option, and after finding a small enough root filesystem courtesy of Aboriginal Linux, a bootable floppy was created. It’s not entirely useful and its sole purpose was to see whether Linux could see a large hard drive on the 486, but it’s still a version 5.6 Linux kernel booting from floppy on an ancient computer. Never complain that your Raspberry Pi Zero is slow again, we’ve come a long way!

Header image — Afrank99 / CC BY-SA 2.0

source https://hackaday.com/2020/07/08/the-latest-linux-on-a-floppy-in-a-486/

Every day, it seems to get harder and harder to relax and unwind. A person can only take so many lava-hot showers before they start cutting into work time. Listening to music is a wonderful option, but it can be difficult to find something to listen to that’s soothing without being disruptive. So what else can we try? Oh yes, blinkenlights. Frosted, glowing blinkenlights that bathe the room in color. Ahhhh.

There’s something about those enclosures that completes these so well. [ChrisParkerTech] used Alder wood sprayed with clear coat, which gives them a delightfully clean mid-century look. We also dig the lack of ceiling and unfinished top edge, because it gives the leaking light a bit of infinity pool mystique.

Of course, these wouldn’t be much of a relaxation tool if you have to get up up from your couch, chair, or bean bag every time you want to adjust them. Each strip is connected to a Wemos D1 mini, so [Chris] can control them with his phone via WLED, or make Alexa do it. Check out the build video after the break.

If you really love LEDs, don’t leave home without them. Show the world how you feel with a stylish LED hat.

source https://hackaday.com/2020/07/07/color-your-workspace-calm-your-mind/

Every day, it seems to get harder and harder to relax and unwind. A person can only take so many lava-hot showers before they start cutting into work time. Listening to music is a wonderful option, but it can be difficult to find something to listen to that’s soothing without being disruptive. So what else can we try? Oh yes, blinkenlights. Frosted, glowing blinkenlights that bathe the room in color. Ahhhh.

There’s something about those enclosures that completes these so well. [ChrisParkerTech] used Alder wood sprayed with clear coat, which gives them a delightfully clean mid-century look. We also dig the lack of ceiling and unfinished top edge, because it gives the leaking light a bit of infinity pool mystique.

Of course, these wouldn’t be much of a relaxation tool if you have to get up up from your couch, chair, or bean bag every time you want to adjust them. Each strip is connected to a Wemos D1 mini, so [Chris] can control them with his phone via WLED, or make Alexa do it. Check out the build video after the break.

If you really love LEDs, don’t leave home without them. Show the world how you feel with a stylish LED hat.

source https://hackaday.com/2020/07/07/color-your-workspace-calm-your-mind/

Every day, it seems to get harder and harder to relax and unwind. A person can only take so many lava-hot showers before they start cutting into work time. Listening to music is a wonderful option, but it can be difficult to find something to listen to that’s soothing without being disruptive. So what else can we try? Oh yes, blinkenlights. Frosted, glowing blinkenlights that bathe the room in color. Ahhhh.

There’s something about those enclosures that completes these so well. [ChrisParkerTech] used Alder wood sprayed with clear coat, which gives them a delightfully clean mid-century look. We also dig the lack of ceiling and unfinished top edge, because it gives the leaking light a bit of infinity pool mystique.

Of course, these wouldn’t be much of a relaxation tool if you have to get up up from your couch, chair, or bean bag every time you want to adjust them. Each strip is connected to a Wemos D1 mini, so [Chris] can control them with his phone via WLED, or make Alexa do it. Check out the build video after the break.

If you really love LEDs, don’t leave home without them. Show the world how you feel with a stylish LED hat.

source https://hackaday.com/2020/07/07/color-your-workspace-calm-your-mind/

One of the perks of using older hardware is its comparative simplicity and extensive documentation. After years or decades of users programming on a platform, the amount of knowledge available for it can become extensive. This is certainly the case with the 6502 microprocessor, used in old Apple computers and some video game systems from the ’80s. The extensive amount of resources available make it a prime candidate in exploring various programming languages, and their advantages and disadvantage.

This project looks into those differences using a robot game, which has been programmed four different ways in three languages. [Joey] created the game in Python first and then began to port it to the 65C02, a CMOS variant of the 6502. The first iteration is its assembly language, and then a second iteration with optimized assembly code. From there, he ports it to C and then finally to Forth. Each version of the game is available to play in a browser using an emulator to run the 6502 hardware.

Since the games run in the browser, other tools are available to examine the way the game runs in each language. Registers can be viewed in real time, as well as the values stored in the memory. It’s an interesting look at an old piece of hardware and of its inner workings. For an even deeper dive into the 6502, it’s possible to build a working computer on breadboards using one.

source https://hackaday.com/2020/07/07/gaming-in-different-languages/

For most people, a broken tool is at the end of its useful life. But rather than toss a heavy-duty drill that had its handle broken off, [Workshop From Scratch] thought it was a perfect opportunity to create something new. In his latest video, he shows how he converted this old hand tool into a magnetic drill press with predictably impressive results.

Despite being assembled largely from pieces of scrap metal cut into shape with an angle grinder, we wouldn’t blame you for believing the end result was a commercial product. From the handles salvaged from chewed up old screwdrivers to the scratch-built rack and pinion assembly, the attention to detail here is really fantastic.

It’s difficult to pick a favorite detail, but the reinvented enclosure for the drill certainly ranks up there. [Workshop From Scratch] could have simply bolted on the tool as-is, but instead he surgically removed the vestigial handle to make it look as though the drill was always meant for this application. After cutting, it was finished off with some body filler, a bit of sanding, and a coat of his signature orange spray paint.

When he built his magnetic vise, [Workshop From Scratch] used magnets pulled from automotive air conditioning systems. They got the job done, but were somewhat annoying to work with given their round shape. This time around, he’s used off-the-shelf magnetic locks intended for steel doors. When energized with a 19 V laptop power supply, he says the three rectangular electromagnets have a combined pull of 540 kilograms.

If you don’t have a broken drill to use as a donor for this type of project, don’t worry. You could always use a salvaged hoverboard motor instead.

source https://hackaday.com/2020/07/07/salvaged-drill-gets-a-magnetic-upgrade/

When we think of lawn mowers, our first thought is of heavy, rusty old machines that take the best part of an afternoon to get started. Of course, there’s always another way, as [Mark] ably demonstrates with his own build. 

Beginning from an unconventional starting point, [Mark] chose a remote control car, of the type that can flip and drive in both orientations. Having lost the controller, he started by ripping out the original electronics. In its place, an ESP32 receives signals from a FlySky RC receiver, and runs the drive motors with a Sparkfun Monster Motor Shield. Another channel on the receiver is hooked up directly to a drone speed controller driving a brushless motor, outfitted with a sawblade to cut the grass.

It’s a small platform, and one that ordinarily you might doubt could do the job. However, for [Mark]’s purposes, the rig works just fine, and has been doing good work for the last two years! We’ve seen mowers hacked before too, like this autonomous rig out in the wild. Video after break.

source https://hackaday.com/2020/07/07/rc-car-becomes-useful-little-mower/

Although you’d be hard-pressed to tell in some areas, it’s summer in the northern hemisphere, which always seems to bring out the projects that require a swimming pool for adequate testing. The [Brick Experiment Channel]’s latest build, a submersible made almost entirely from Lego, is one such project and has us pining for weather that makes a dip sensible rather than suicidal.

The sub featured in the video below is a significant improvement over the “Sub in a Jug” approach the [Brick Experiment Channel] favored for version 1. Rather than starting with a vessel specifically designed not to hold water, the hull for this vessel is an IKEA food container, with a stout glass body and a flexible lid with silicone seals. And instead of penetrating the hull for driveshafts and attempting to seal them, this time around he built clever magnetic couplings.

The couplings transmit torque from the motors on the inside to gears and props on the outside. And where the first version used a syringe-pump ballast tank to control the depth, this one uses vertical thrusters. The flexible lid proved to be a problem with that scheme, since it tended to collapse as the depth increased, preventing the sub from surfacing. That was solved with some Lego bracing and adjustment of the lead shot ballast used to keep the sub neutrally buoyant.

This looks like a ton of summer fun, and even if you don’t have Legos galore to work with, it could easily be adapted to other materials. There are a ton of other fun [BEC] Lego builds to check out, some of which we’ve covered, including a Lego drone and a playing card shooter.

Thanks for the tip, [Vox]!

source https://hackaday.com/2020/07/07/magnetic-couplings-make-this-lego-submarine-watertight/

If you’ve used KiCad before, you’re certainly familiar with the handy 3D view that shows you a rendered view of what your assembled board would look like. But as [Vadim Panov] explains, you can take this capability a step further. With a few extra tools and a little bit of know-how, you can leverage KiCad’s PCB renderings to make custom 3D printable enclosures.

The first step is to design the PCB as you normally would in KiCad. This could be an original PCB of your own invention, or a digital representation of an off-the-shelf model you want to build an enclosure for. If the latter, then the PCB doesn’t need to be 100% accurate; the goal is really just to get the big components into roughly the right areas so you can get the clearances right. Though obviously you’ll want to make sure the board’s outer dimensions and mounting hole locations are recreated as accurately as possible.

From there, [Vadim] recommends a tool called StepUp. This will take your PCB KiCad PCB files and create either a STEP or STL file of the assembled board which can be imported into your CAD package of choice. For the purposes of this demonstration he’s sticking with FreeCAD, as he likes the idea of it being a completely FOSS toolchain from start to finish.

Now that you have a model of the PCB in your CAD software, the rest is up to you. Naturally, there are existing enclosure models you can use such as the ones produced by the “Ultimate Box Maker” that we covered previously, but you could just as easily start building a new enclosure around the digital PCB.

Looking for a bit more guidance? As it so happens, our very own [Anool Mahidharia] will be presenting a class on how you can develop a KiCad + FreeCAD workflow as part of our recently launched HackadayU initiative.

source https://hackaday.com/2020/07/07/designing-3d-printed-enclosures-for-kicad-pcbs/

[Zach] over at his channel Breaking Taps has put up an extraordinary account on manufacturing some homemade acrylic lenses. In the end, not only does he produce some beautiful concave lenses, he also covers the complete manufacturing process, from milling the aluminium die used for injection moulding to tweaking the parameters associated with injecting the actual acrylic, he even goes over the limitations of optics produced in this fashion.

What caught our eye in particular, was how [Zach] used the finished product to practically demonstrate photoelasticity originating from the stress induced by the moulding process. You might be familiar with describing the optical properties of a material by a single number, i.e its permittivity. But what happens if in addition to altering speed, the material also alters the polarisation and direction of light depending on the stress distribution within the material? Whilst a quantitative answer gets a bit complicated you can check out [Zach’s] additional videos to visualise the answer in a pretty and colourful way, without resorting to fancy computer simulations! If however, you really want to persist with the simulation route, check out our article on stress analysis in a totally different setting using Finite Element Analysis.

source https://hackaday.com/2020/07/07/milling-dies-and-injection-moulding-some-acrylic-lenses/

[Zach] over at his channel Breaking Taps has put up an extraordinary account on manufacturing some homemade acrylic lenses. In the end, not only does he produce some beautiful concave lenses, he also covers the complete manufacturing process, from milling the aluminium die used for injection moulding to tweaking the parameters associated with injecting the actual acrylic, he even goes over the limitations of optics produced in this fashion.

What caught our eye in particular, was how [Zach] used the finished product to practically demonstrate photoelasticity originating from the stress induced by the moulding process. You might be familiar with describing the optical properties of a material by a single number, i.e its permittivity. But what happens if in addition to altering speed, the material also alters the polarisation and direction of light depending on the stress distribution within the material? Whilst a quantitative answer gets a bit complicated you can check out [Zach’s] additional videos to visualise the answer in a pretty and colourful way, without resorting to fancy computer simulations! If however, you really want to persist with the simulation route, check out our article on stress analysis in a totally different setting using Finite Element Analysis.

source https://hackaday.com/2020/07/07/milling-dies-and-injection-moulding-some-acrylic-lenses/