A Reason To Code

My son is just getting to the age that puts him in the crosshairs of all of the learn-to-code toys. And admittedly, we’ve been looking at some of those Logo-like toys where you can instruct a turtle-bot to make a few moves, and then to repeat them. After all, if breaking down a problem into sub-problems and automating the repetition isn’t the essence of programming, I don’t know what is.

But here’s the deal: I think drawing ‘bots are cooler than he does. If you ask a kid “hey, do you want a car that can draw?” that’s actually pretty low on the robot list. I’m not saying he won’t get into it once he’s got a little bit more coding under his belt and he can start to make it do fun things, but by itself, drawing just isn’t all that impressive. He can draw just fine, thank-you-very-much.

Meanwhile, I was making a robot arm. Or rather, I started up on yet another never-to-be-completed robot arm. (Frankly, I don’t know what I would do with a robot arm.) But at least I started with the gripper and wrist. Now that’s pretty cool for a kid, but the programming is waaaay too complicated. So I pulled the brains out and hooked up the servos to an RC plane remote. Just wiggling the thing around, duct-taped to the table, got him hooked. And this weekend, we’re building a remote controlled cherry-picker arm to put on a pole, because cherries are in season. His idea!

So no coding. He’s a little too young anyway, IMO. But silly little projects like these, stored deep in his subconscious, will give him a reason to program in the future, will make it plainly obvious that knowing how to program is useful. Now all I need is a reason to finish up a robot arm project…

Hackaday Links: June 21, 2020

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.


Machine Builds Rise From The Ashes

I was enchanted by a failed project this week. [Andrew Consroe]’s CNC scroll saw doesn’t work yet, but the emphasis is on the word “yet”. Heck, even when it does work, it might not make sense, but that’s not the point anyway.


A scroll saw table has a vertical reciprocating blade perpendicular to a table, a lot like a band saw but with a shorter blade. You push the wood sheet to be cut into the blade, and because it’s thin, you can twist and turn all sorts of interesting jigsaw-puzzle shapes. [Andrew] automated this with an X-Y gantry and an innovative geared rotating ring, needed to keep the wood fed into the cutting edge of the blade.

It’s a crazy contraption, and a difficult and unique movement planning problem, and watching it move in the video is a joy. But it’s not working either: errors in the motion add up over a cut, and he’s ended up snapping a blade on every piece. And this is version three of the device!

But here comes the inspiration. First, the only reason he’s filming this is to keep a log of how the project looked at this phase — he’s already planning out the next one. Second, this is the soul of learning by doing. You don’t learn anything unless you’re trying something new.

And finally, [Andrew]’s project reminds me of why I love machine builds in the age of rapid prototyping. Blazing through three entirely different machines cost him essentially nothing. Tearing apart version one left him with the same stepper motors, aluminum extrusions, and electronics as when he started out. Except that he now knew so much more about his particular problem space. Now he’s ready to go again.

So if you’re at all robotically inclined, but you’re looking at the cost of motors, belts, bearings, and steel, don’t think of it as an expense for this project, but for years’ worth of iterations, and maybe even fully different machines.

Just be sure to take [Andrew]’s lead and get it down and documented before you take it apart! Heck, send it in to Hackaday and it’ll live forever.

A New KiCAD Tutorial Hits The Scene

KiCAD has a rightfully earned image problem regarding beginners. The shiny new version 5 has improved things (and we’re very excited for v6!) but the tool is a bit obtuse even when coming from a electronics design background, so we’re always excited to see new learning material. [Mike Watts] is the latest to join the esteemed group of people willing to export their knowledge with his KiCAD tutorial series on GitHub that takes the aspiring user from schematic through fab and assembly.

The tutorial is focused around the process of creating a development board for the dimuitive Microchip née Atmel ATSAMD10 Cortex M0 ARM CPU. It opens by asking the reader to create a schematic and proceeds to teach by directing them to perform certain actions then explaining what’s going on and which shortcuts can accelerate things. This method continues through layout, manufacturing, and assembly.

Of note is that when defining the board outline [Mike] describes how to use OpenSCAD to parametrically define it; a neat micro-tutorial on using the two great tools to compliment each other. We also love that upon successful completion of the tutorial series the user will have developed a tiny but useful development board that can be assembled for about $3 in single quantities!

As with all open source work, if you have quibbles or want to contribute open a pull request and give [Mike] a hand!

Byte Sized Pieces Help The KiCad Go Down

It’s no surprise that we here at Hackaday are big fans of Fritzing KiCad. But to a beginner (or a seasoned veteran!) the learning curve can be cliff-like in its severity. In 2016 we published a piece linking to project by friend-of-the-Hackaday [Chris Gammell] called Contextual Electronics, his project to produce formalized KiCad training. Since then the premier “Getting to Blinky” video series has become an easy recommendation for anyone looking to get started with Libre EDA. After a bit of a hiatus [Chris] is back with bite sized videos exploring every corner of the KiCad-o-verse.

A Happy [Chris] comes free with every video
The original Getting to Blinky series is a set of 10 videos up to 30 minutes long that walks through everything from setting up the the KiCad interface through soldering together some perfect purple PCBs. They’re exhaustive in coverage and a great learning resource, but it’s mentally and logistically difficult to sit down and watch hours of content. Lately [Chris] has taken a new tack by producing shorter 5 to 10 minute snapshots of individual KiCad features and capabilities. We’ve enjoyed the ensuing wave of learning in our Youtube recommendations ever since!

Selecting traces to rip up

Some of the videos seem simple but are extremely useful. Like this one on finding those final disconnected connections in the ratsnest. Not quite coverage of a major new feature, but a topic near and dear to any layout engineer’s heart. Here’s another great tip about pulling reference images into your schematics to make life easier. A fantastic wrapped up in a tidy three minute video. How many ways do you think you can move parts and measure distances in the layout editor? Chris covers a bunch we hadn’t seen before, even after years using KiCad! We learned just as much in his coverage of how to rip up routed tracks. You get the idea.

We could summarize the Youtube channel, but we aren’t paid by the character. Head on down to the channel and find something to learn. Make sure to send [Chris] tips on content you want him to produce!

Robot Arm Is A Fast Learner

Not long ago, machines grew their skills when programmers put their noses to the grindstone and mercilessly attacked those 104 keys. Machine learning is turning some of that around by replacing the typing with humans demonstrating the actions they want the robot to perform. Suddenly, a factory line-worker can be a robot trainer. This is not new, but a robot needs thousands of examples before it is ready to make an attempt. A new paper from researchers at the University of California, Berkeley, are adding the ability to infer so robots can perform after witnessing a task just one time.

A robotic arm with no learning capability can only be told to go to (X,Y,Z), pick up a thing, and drop it off at (X2, Y2, Z2). Many readers have probably done precisely this in school or with a homemade arm. A learning robot generates those coordinates by observing repeated trials and then copies the trainer and saves the keystrokes. This new method can infer that when the trainer picks up a piece of fruit, and drops it in the red bowl, that the robot should make sure the fruit ends up in the red bowl, not just the location where the red bowl was before.

The ability to infer is built from many smaller lessons, like moving to a location, grasping, and releasing and those are trained with regular machine learning, but the inference is the glue that holds it all together. If this sounds like how we teach children or train workers, then you are probably thinking in the right direction.

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This Machine Teaches Sign Language

Sign language can like any language be difficult to learn if you’re not immersed in it, or at least learning from someone who is fluent. It’s not easy to know when you’re making minor mistakes or missing nuances. It’s a medium with its own unique issues when learning, so if you want to learn and don’t have access to someone who knows the language you might want to reach for the next best thing: a machine that can teach you.

This project comes from three of [Bruce Land]’s senior electrical and computer engineering students, [Alicia], [Raul], and [Kerry], as part of their final design class at Cornell University. Someone who wishes to learn the sign language alphabet slips on a glove outfitted with position sensors for each finger. A computer inside the device shows each letter’s proper sign on a screen, and then checks the sensors from the glove to ensure that the hand is in the proper position. Two letters include making a gesture as well, and the device is able to track this by use of a gyroscope and compass to ensure that the letter has been properly signed. It appears to only cover the alphabet and not a wider vocabulary, but as a proof of concept it is very effective.

The students show that it is entirely possible to learn the alphabet reliably using the machine as a teaching tool. This type of technology could be useful for other applications as well, such as gesture recognition for a human interface device. If you want to see more of these interesting and well-referenced senior design builds we’ve featured quite a few, from polygraph machines to a sonar system for a bicycle.

Continue reading “This Machine Teaches Sign Language”