Month: December 2019

Testing Carbon Fibre Reinforced Filament By Building An Over-Engineered Skateboard

December 3, 2019 by 4 Comments

Advances in filaments for FDM 3D printers have come in leaps and bounds over the past few years, and carbon fibre (CF) reinforced filament is becoming a common sight. Robotics extraordinaire [James Bruton] got his hands on some CF reinforced PLA, and ended up building a completely over-engineered 3D printed skateboard. (Video, embedded below.)

[James] started by printing some test pieces with a 0.5 mm and a big 1.2 mm nozzle with and without the CF, which he subjected to cantilever deflection tests. The piece with CF was 20% stiffer than without.

[James] then built an extremely strong and cool looking skateboard deck with alternating section of the CF PLA and toughened PLA, totalling 2.7 kg of filament. It was extremely strong, so after bolting on a set of trucks and wheels, he did some mild riding at a local skate park, where it survived without any problems. He admits it was completely over-engineered, but points out in that the internal cavities in the deck is the perfect place for batteries on an electric long board.

Designing something from the ground up with the strength and weaknesses 3D printing in mind, leads to some very interesting and innovative designs, of which this is a perfect example, and we hope to see many more like it. We’ve featured a number of [James]’ project, including the remote controlled bowling ball he built for [Mark Rober] and his impressive OpenDog and Start Wars robots.

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Electric Dreams Help Cows Survive The Desert Of The Real

December 3, 2019 by 64 Comments

Pictures of a cow wearing a pair of comically oversized virtual reality goggles recently spread like wildfire over social media, and even the major news outlets eventually picked it up. Why not? Nobody wants to read about geopolitical turmoil over the holidays, and this story was precisely the sort of lighthearted “news” people would, if you can forgive the pun, gobble up.

But since you’re reading Hackaday, these images probably left you with more questions than answers. Who made the hardware, what software is it running, and of course, why does a cow need VR? Unfortunately, the answers to the more technical questions aren’t exactly forthcoming. Even tracking the story back to the official press release from the Ministry of Agriculture and Food of the Moscow Region doesn’t tell us much more than we can gather from the image itself.

But it does at least explain why somebody went through the trouble of making a custom bovine VR rig: calm cows produce more milk. These VR goggles, should they pass their testing and actually be adopted by the Russian dairy industry, will be the newest addition to a list of cow-calming hardware devices that farmers have been using for decades to get the most out of their herds.

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The Open Makers Cube: Have Hack, Will Travel

December 3, 2019 by 10 Comments

Don’t bother denying it, we know your workbench is a mess. A tangled pile of wires, tools, and half-completed projects is standard decor for any hardware hacker. In fact, if you’ve got a spotless work area, we might even be a bit skeptical about your credentials in this field. But that’s not to say we wouldn’t be interested in some way of keeping the electronic detritus in check, perhaps something like the Open Makers Cube created by [technoez].

This all-in-one hardware hacking station uses DIN rails and 3D-printed mounting hardware to allow the user to attach a wide array of tools, gadgets, and boards to the outside surface where they’re easily accessible. The OpenSCAD design includes mounts for the usual suspects like the Raspberry Pi, Arduino Uno, and general purpose breadboards. Of course, your own custom mounts are just a few lines of code away.

The Cube also includes a lighted magnifying glass on a flexible arm so you can zoom in on what you’re working on, a simple “helping hands” attachment, and provisions for internal USB power. It even features angled feet so the front side of the cube is held at a more comfortable viewing angle. All of which is held together by a lightweight and portable frame built from square aluminum tubing.

We can understand if you’ve got some doubts about the idea of mounting all of your tools and projects to the side of a jaunty little cube. But even if the jury is still out on the mobile workspace concept, one thing is for sure: the Open Makers Cube is easily one of the best documented projects we’ve seen in recent memory. Thanks to NopSCADlib, [technoez] was able to generate an exploded view and Bill of Materials for each sub-assembly of the project. If you’ve ever needed proof that NopSCADlib was worth checking out, this is it.

Building A Mechanical Oscillator, Tesla Style

December 3, 2019 by 12 Comments

Before Tesla devised beautifully simple rotary machinery, he explored other methods of generating alternating current. One of those was the mechanical oscillator, and [Integza] had a go at replicating the device himself. (Video, embedded below the break.)

Initial attempts to reproduce the technology using 3D-printed parts were a failure. The round cylinder had issues sealing, and using O-ring seals introduced too much friction to allow the device to oscillate properly. A redesign that used external valving and a square cylinder proved more successful.

Once the oscillator was complete, the output shaft was fitted with magnets and a coil to generate electricity. After generating a disappointing 0.14 volts, [Integza] went back and had a look at the Maxwell-Faraday equations. Using this to guide the design, a new coil was produced with more turns, and the magnetic flux was maximised. With this done, the setup could generate seven volts, enough to light several LEDs.

While it’s not a particularly efficient generator, it’s a great proof-of-concept. Yes, Tesla’s invention worked, but it’s easy to see why he moved on to rotary designs when it came to real-world applications. We’ve seen [Integza] take on other builds too, like the ever-popular Tesla turbine.

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Fun With A 200-kW Fiber Laser

December 2, 2019 by 23 Comments

We’ve all heard the “Do not stare into laser with remaining eye” joke. It’s funny because it’s true, as pretty much any laser a hobbyist can easily come by can cause permanent damage to eyes unless the proper precautions are taken. But a fiber laser with 200kW peak power is in another hazard class entirely.

Granted, outsized power ratings like this are a bit misleading, based as they are on femtosecond-long pulses. And to be sure, the fiber laser that [Marco Reps] tears down in the video below was as harmless as a kitten when he got it, thanks to its output optics having been unceremoniously shorn from the amplifier by its former owner. Reattaching the output and splicing the fiber would be necessary to get the laser lasing again, but [Marco] had other priorities in mind. He wanted to understand the operation of a fiber laser, but the tangle of fibers on two separate levels inside the chassis was somewhat inscrutable. The coils of fiber wrapped around the aluminum drums inside the chassis turned out to be the amplifier; fed by a semiconductor seed laser, the light pulse travels through the ytterbium-doped fiber of the two-stage amplifier, which is the active gain medium where stimulated emission, and therefore amplification, occurs.

With a little reverse engineering and the help of an online manual, he was able to understand the laser’s operation. A laser company helped him splice the optics back together – seeing the splicing rig in action is worth the price of admission alone – and the unit seems to be in more or less working order at this point. Normally the most powerful laser we see around here are the CO2 lasers in those cheap Chinese laser cutters, so we’re looking forward to learning more about fiber lasers.

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Self-Driving Cars Are Predicting Driving Personalities

December 2, 2019 by 29 Comments

In a recent study by a team of researchers at MIT, self driving cars are being programmed to identify the social personalities of other drivers in an effort to predict their future actions and drive safer on roads.

It’s already been made evident that autonomous vehicles lack social awareness. Drivers around a car are regarded as obstacles rather than human beings, which can hinder the automata’s ability to identify motivations and intentions, potential signifiers to future actions. Because of this, self-driving cars often cause bottlenecks at four-way stops and other intersections, perhaps explaining why the majority of traffic accidents involve them getting rear-ended by impatient drivers.

The research taps into social value orientation, a concept from social psychology that classifies a person from selfish (“egoistic”) to altruistic and cooperative (“prosocial”). The system uses this classification to create real-time driving trajectories for other cars based on a small snippet of their motion. For instance, cars that merge more often are deemed as more competitive than other cars.

When testing the algorithms on tasks involving merging lanes and making unprotected left turns, the behavioral predictions were shown to improve by a factor of 25%. In a left-turn simulation, the automata was able to wait until the approaching car had a more prosocial driver.

Even outside of self-driving cars, the research could help human drivers predict the actions of other drivers around them.

Thanks [Qes] for the tip!

Vintage Plotter Gets Bluetooth Upgrade

December 2, 2019 by 25 Comments

Recently [iot4c] stumbled upon this gorgeous Robotron Reiss plotter from 1989, brand-new and still in its original box. Built before the fall of the Berlin Wall in East Germany, it would be a crime to allow such a piece of computing history to go unused. But how to hook it up to a modern system? Bad enough that it uses some rather unusual connectors, but it’s about to be 2020, who wants to use wires anymore? What this piece of Cold War hardware needed was an infusion of Bluetooth.

While the physical ports on the back of the Robotron certainly look rather suspect, it turns out that electrically they’re just RS-232. In practice, this means converting it over was fairly straightforward. With a Bolutek BK3231 Bluetooth module and an RS-232 to UART converter, [iot4c] was able to create a wireless adapter that works transparently on the plotter by simply connecting it to the RX and TX pins.

A small DC buck converter was necessary to provide 3.3 V for the Bluetooth adapter, but even still, there was plenty of room inside the plotter’s case to fit everything in neatly. From the outside, you’d have no idea that the hardware had ever been modified at all.

But, like always, there was a catch. While Windows had no trouble connecting to the Bluetooth device and assigning it a COM port, the 512 byte buffer on the plotter would get overwhelmed when it started receiving commands. So [iot4c] wrote a little script in Node.js that breaks the commands down into more manageable chunks and sends them off to the plotter every 0.1 seconds. With this script in place the Robotron moved under its own power for the first time in ~30 years by parsing a HP-GL file generated by Inkscape.

If you’re interested in a plotter of your own but don’t have a vintage one sitting around, never fear. We’ve seen an influx of DIY plotters recently, ranging from builds that use popsicle sticks and clothespins to customizable 3D printed workhorses.