Voice-Command Chess Board Powered By Alexa

June 22, 2020 by Lewin Day 6 Comments

Talking to computers used to be reserved for Star Trek and those with overactive imaginations. Now, it’s a regular part of daily life. [CodersCafe] decided to put this technology to work in a chess robot, with the help of Amazon’s digital assistant.

The build relies on an Cartesian motion rig, built out of Lego Technics parts. The end effector is fitted with a magnet , fitted onto the Z-axis screw for engaging and disengaging with the pieces. A Mindstorms EV3 controller is used to run the show, hooked up over Bluetooth to an Amazon Echo. This allows the user to ask Alexa to move the pieces for the white player in natural language – by saying, for example, “move from B1 to C3”.

It’s a build that demonstrates how easy it is to create projects with advanced functionality by lacing together the correct off-the-shelf hardware. Other Cartesian-type motion platforms can make great chess robots, too. Video after the break.

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Hackaday Links: June 21, 2020

June 21, 2020 by Dan Maloney 19 Comments

When Lego introduced its Mindstorms line in 1998, in a lot of ways it was like a gateway drug into the world of STEM, even though that term wouldn’t be invented for another couple of years. Children and the obsolete children who begat them drooled over the possibility of combining the Lego building system with motors, sensors, and a real computer that was far and away beyond anything that was available at the time. Mindstorms became hugely influential in the early maker scene and was slowly but steadily updated over the decades, culminating with the recently released Mindstorms Robot Inventor kit. In the thirteen years since the last release, a lot has changed in the market, and we Hackaday scribes had a discussion this week about the continued relevancy of Mindstorms in a time when cheap servos, microcontrollers, and a bewildering array of sensors can be had for pennies. We wonder what the readers think: is a kit that burns a $360 hole in your pocket still worth it? Sound off below.

Are you looking for a way to productively fill some spare time? Plenty of people are these days, and Hackaday has quite a deal for them: Hackaday U! This series of online courses will get you up to speed on a wide range of topics, starting tomorrow with Matthew Alt’s course on reverse engineering with Ghidra. Classes meet online once a week for four weeks, with virtual office hours to help you master the topic. Beside reverse engineering, you can learn about KiCad and FreeCad, quantum computing, real-time processing of audio and sensor data, and later in the year, basic circuit theory. We’ve got other courses lined up to fill out the year, but don’t wait — sign up now! Oh, and the best part? It’s on a pay-as-you-wish basis, with all proceeds going to charity. Get smarter, help others while doing it — what’s not to love about that?

Speaking of virtual learning, the GNU Radio Conference will be moving online for its 10th anniversary year. And while it’s good news that this and other cons have been able to retool and continue their mission of educating and growing this community, it’s still a bummer that there won’t be a chance to network and participate in all the fun events such cons offer. Or perhaps there will — it seems like the Wireless Capture the Flag (CTF) event is still going to happen. Billed as “an immersive plot-driven … competition featuring the GNU Radio framework and many other open-source tools, satellite communications, cryptography, and surreal global landscapes,” it certainly sounds like fun. We’d love to find out exactly how this CTF competition will work.

Everyone needs a way to unwind, and sometimes the best way to do that is to throw yourself into a project of such intricacy and delicate work that you’re forced into an almost meditative state by it. We’ve seen beautiful examples of that with the wonderful circuit sculptures of Mohit Bhoite and Jiří Praus, but here’s something that almost defies belief: a painstakingly detailed diorama of a vintage IBM data center. Created by the aptly named [minatua], each piece of this sculpture is a work of art in its own right and represents the “big iron” of the 1400 series of computers from the early 1960s. The level of detail is phenomenal — the green and white striped fanfold paper coming out of the 1403 line printer has tiny characters printed on it, and on the 729 tape drives, the reels spin and the lights flash. It’s incredible, all the more so because there don’t appear to be any 3D-printed parts — everything is scratch built from raw materials. Check it out.

As you can imagine, the Hackaday tip line attracts a fair number of ideas of the scientifically marginal variety. Although we’re not too fond of spammers, we try to be kind to everyone who bothers to send us a tip, but with a skeptical eye when terms like “free energy” come across. Still, we found this video touting to Nikola Tesla’s free energy secrets worth passing on. It’s just how we roll.

And finally, aside from being the first full day of summer, today is Father’s Day. We just want to say Happy Father’s Day to all the dads out there, both those that inspired and guided us as we were growing up, and those who are currently passing the torch to the next generation. It’s not easy to do sometimes, but tackling a project with a kid is immensely important work, and hats off to all the dads who make the time for it.

Hackaday Links: June 14, 2020

June 14, 2020 by Dan Maloney 17 Comments

You say you want to go to Mars, but the vanishingly thin atmosphere, the toxic and corrosive soil, the bitter cold, the deadly radiation that sleets down constantly, and the long, perilous journey that you probably won’t return from has turned you off a little. Fear not, because there’s still a way for you to get at least part of you to Mars: your intelligence. Curiosity, the Mars rover that’s on the eighth year of its 90-day mission, is completely remote-controlled, and NASA would like to add some self-driving capabilities to it. Which is why they’re asking for human help in classifying thousands of images of the Martian surface. By annotating images and pointing out what looks like soil and what looks like rock, you’ll be training an algorithm that one day might be sent up to the rover. If you’ve got the time, give it a shot — it seems a better use of time than training our eventual AI overlords.

We got a tip this week that ASTM, the international standards organization, has made its collection of standards for testing PPE available to the public. With titles like “Standard Test Method for Resistance of Medical Face Masks to Penetration by Synthetic Blood (Horizontal Projection of Fixed Volume at a Known Velocity)”, it seems like the standards body wants to make sure that that homebrew PPE gets tested properly before being put into service. The timing of this release is fortuitous since this week’s Hack Chat features Hiram Gay and Lex Kravitz, colleagues from the Washington University School of Medicine who will talk about what they did to test a respirator made from a full-face snorkel mask.

There’s little doubt that Lego played a huge part in the development of many engineers, and many of us never really put them away for good. We still pull them out occasionally, for fun or even for work, especially the Technic parts, which make a great prototyping system. But what if you need a Technic piece that you don’t have, or one that never existed in the first place? Easy — design and print your own custom Technic pieces. Lego Part Designer is a web app that breaks Technic parts down into five possible blocks, and lets you combine them as you see fit. We doubt that most FDM printers can deal with the fine tolerances needed for that satisfying Lego fit, but good enough might be all you need to get a design working.

Chances are pretty good that you’ve participated in more than a few video conferencing sessions lately, and if you’re anything like us you’ve found the experience somewhat lacking. The standard UI, with everyone in the conference organized in orderly rows and columns, reminds us of either a police line-up or the opening of The Brady Bunch, neither of which is particularly appealing. The paradigm could use a little rethinking, which is what Laptops in Space aims to do. By putting each participant’s video feed in a virtual laptop and letting them float in space, you’re supposed to have a more organic meeting experience. There’s a tweet with a short clip, or you can try it yourself. We’re not sure how we feel about it yet, but we’re glad someone is at least trying something new in this space.

And finally, if you’re in need of a primer on charlieplexing, or perhaps just need to brush up on the topic, [pileofstuff] has just released a video that might be just what you need. He explains the tri-state logic LED multiplexing method in detail, and even goes into some alternate uses, like using optocouplers to drive higher loads. We like his style — informal, but with a good level of detail that serves as a jumping-off point for further exploration.

Lego Microscope Does Research

May 5, 2020 by Al Williams 10 Comments

We’ve seen a lot of practical machines built using Lego. Why not? The bricks are cheap and plentiful, so if they can get the job done, who cares if they look like a child’s toy? Apparently, not [Yuksel Temiz]. He’s an engineer for IBM whose job involves taking pictures of microscopic fluidic circuits. When he wasn’t satisfied with the high-power $10,000 microscopes he had, he built his own. Using Lego. How are the pictures? Good enough to appear in many scientific journals.

Clearly, the microscope doesn’t just contain Lego, but it still came in at under $300. According to an interview from Futurism, the target devices are reflective which makes photographing them straight-on difficult. After experimenting with cameras on tripods, [Yuksel] decided he could build his own specialized device. You can see a video of the devices in question and some of the photographs below.

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A Lego Tensegrity Structure

April 28, 2020 by Moritz v. Sivers 14 Comments

Tensegrity structures are an impressive demonstration of how to achieve mechanical stability through tensile forces. Since the topic is currently trending it was probably only a matter of time before somebody like [Alexandre Thiery] came with the idea to build a tensegrity model from Lego.

In the GIF below that [Alexandre Thiery] shared on his Twitter account you can see his kids admiring the model. Tensegrity structures consist of elements under constant tension – in most cases strings – and components under compression, in this case beams of Lego. By combining these elements, one can build stable structures that seem to float in midair. A simple daily-life example for tensegrity is a balloon where the skin is the tensional element while the air inside is the component under compression.

[Alexandre Thiery] has come up with the clever idea to simply clamp the strings between two Lego blocks. This certainly paves the way for other more complicated Lego-based tensegrity structures that we will likely see in the future. [Alexandre Thiery] also recently extended his model by stacking an identical structure on top of it.

If you do not have any Lego at hand just fire up your 3D printer to make a tensegrity physics toy or a floating table.

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Build The Baddest Keypad On The Block With LEGO

April 24, 2020 by Kristina Panos 1 Comment

Like so many of us, [EducatedAce] has been quelling the quarantine blues by resurrecting old projects and finding new challenges to fill the days. He’s just finished building this blocky macro keypad to hold a bunch of shortcuts for Photoshop, thus continuing and compounding the creative spree.

[EducatedAce] already had everything on hand except the Arduino Micro. Instead of standard key switches, this macro block uses 16 of the loudest, crunchiest tactile buttons out there — those big ones with the yellow stems that sound like small staplers.

And don’t worry — no LEGO or LEGO accessories were harmed in the making of this macro pad — the base plate and switch plate are 3D printed. [EducatedAce] has the STL files posted along with great build instructions if you want to wire one up for yourself.

This is a great project because it’s sturdy, it gets the job done without a lot of expense, and still looks like something you’d want on your desk. [EducatedAce] plans to rebuild it with uniformly colored bricks, but we think it looks great as-is, especially with those vented 1×2 pieces. If it were ours, we might use a different color for each row or column to help keep the shortcuts straight.

What? You’ve never printed your own interlocking building blocks before? Well, don’t limit yourself to 1:1 scale, otherwise the minifigs have won. Build a go-kart big enough for humans!

Huge 3D-Printed LEGO Go Kart Makes You The Minifig

April 19, 2020 by Mike Szczys 7 Comments

The LEGO Technic line is definitely the hacker’s flavor of LEGO. It brings a treasure trove of engineering uses that make axles, gears, pulleys, and motors a thing. The only problem is that it’s the inanimate minifigures having all of the fun. But not if [Matt Denton] has something to say about it. He’s building a huge 3D-printed go-kart with pieces scaled up 8.43 times the size of their LEGO equivalents. That’s large enough for an adult to fit!

You may remember seeing [Matt’s] previous attempt at something like this about three years back, but that was only around half the size of this one. He printed a blue kart for his nephew, but it didn’t quite scale up enough even for a child to ride. This one is impressively large, but that raises some interesting fabrication issues

The long beams that make up the frame of the vehicle and the axle piece (the black rods with an X-shaped profile) used for the steering column are far too long to print in one go. So the axle was printed in two parts with a square channel down the center that hides a single run of square tubing. But the beams are much more interesting. Printed in two parts, there’s a dovetail-shaped connector piece that holds the top joint together, and a hidden bolt for the bottom. Glue is also used along the joint to bolster the holding power of the mechanical fasteners.

In general, the weight and friction on this scaled up version need many considerations. [Matt] explains where he’s made design decisions — like perpendicular axle connectors that have proper bearings — to include mostly-hidden metal parts and fasteners to ensure the plastic doesn’t fail. The thing looks awesome, but just wait until you see the assembly process. It’s sooooo satisfying to watch the modular parts snap into place. The project’s still in progress and before he’s done he plans to add an electric motor to make the kart go.

Even if you’re not scaling a model up to full size, giant is a guaranteed recipe for fun. Case in point, [Matt’s] enlarged LEGO fork lift is a delight.

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