Honor Your Hacker Heroes

We recently ran an article on a sweet percussion device made by minimal-hardware-synth-madman [Gijs Gieskes]. Basically, it amplifies up an analog meter movement and plays it by slamming it into the end stops. Rhythmically, and in stereo. It’s got that lovely thud, plus the ringing of the springs. It takes what is normally a sign that something’s horribly wrong and makes a soundtrack out of it. I love it.

[Gijs] has been making electro-mechanical musical hacks for about as long as I’ve been reading Hackaday, if not longer. We’ve written up no fewer than 22 of his projects, and the first one on record is from 2005: an LSDJ-based hardware sequencer. All of his projects are simple, but each one has a tremendously clever idea at its core that comes from a deep appreciation of everything going on around us. Have you noticed that VU meters make a particular twang when they hit the walls? Sure you have. Have you built a percussion instrument out of it? [Gijs] has!

Maybe it’s a small realization, and it’s not going to change the world by itself, but I’ve rebuilt more than a couple projects from [Gijs]’ repertoire, and each one has made my life more fun. And if you’re a regular Hackaday reader, you’ve probably seen hundreds or thousands of similar little awesome ideas played out, and maybe even taken some of them on as your own as well. When they accumulate up, I believe they can change the world, at least in the sense of filling up a geek’s life. I hope that feeling comes across when we write up a project. Those of you out there hacking, we salute you!

Inspiring Hacks, Unfinished Hacks

We got a tip this week, and the tipster’s comments were along the lines of “this doesn’t look like it’s a finished work yet, but I think it’s pretty cool anyway”. And that was exactly right. The work in question is basically attaching a simple webcam to a CNC router and then having at it with OpenCV, and [vector76]’s application was cutting out freeform hand-drawn curves from wood. To amuse his daughter.

But there’s no apology necessary for presenting a work in progress. Unfinished hacks are awesome! They leave room for further improvement and interpretation. They are like an unfinished story, inviting the hacker to dream up their own end. At least that’s how this one worked on me.

My mind went racing — adding smart and extensible computer vision to a CNC router enables not only line tracing, but maybe smarter edge finding, broken tool detection, and who knows what else. With the software end so flexible these days, and the additional hardware demands so minimal, it’s an invitation. It’s like Pavlov ringing that bell, and I’m the dog-hacker. Or something.

So remember this when you get half done with a project, get to a workable first-stage demo, but you haven’t chased down each and every possibility. Leaving something up to other hackers’ imagination can be just as powerful. Your proof of concept doesn’t have to be the mother of all demos — sometimes just a working mouse will suffice.

Finding The Right Hack Is Half The Battle

Sometimes you just get lucky. I had a project on my list for a long time, and it was one that I had been putting off for a few months now because I loathed one part of what it entailed — sensitive, high-accuracy analog measurement. And then, out of the blue I stumbled on exactly the right trick, and my problems vanished in thin air. Thanks, Internet of Hackers!

The project in question is a low-vacuum regulator for “bagging” fiberglass layups. What I needed was some way to read a pressure sensor and turn on and off a vacuum pump accordingly. The industry-standard vacuum gauges are neat devices, essentially a tiny little strain gauge on a membrane between the vacuum side and the atmosphere side, in a package the size of a dime. (That it’s a strain gauge is foreshadowing, but I didn’t know that at the time.) I bought one for $15 ages ago, and it sat on my desk, awaiting its analog circuitry.

See, the MPX2100 runs on 12 V and puts out a signal around 40 mV on top of a 6 V offset. That voltage level is inconvenient for modern 3.3 V microcontroller ADCs, and the resolution would get clobbered by the 6 V signal if I just put a voltage divider on it. This meant whipping together some kind of instrument amplifier circuit to null out the 6 V and amplify the 40 mV for the ADC. The circuits I found online all called for 1% resistors in values I didn’t have, and mildly special op-amps. No fun, for me at least. So there it sat.

Picture of sketchy-looking vacuum apparatus.
Cut the blue wire or the red wire? HX711 module and pressure sensor on the left.

Until I ran into this project that machetes through the analog jungle with one part, and it happened to be one I had on hand. A vacuum pressure sensor is a strain gauge, set up like a Wheatstone bridge, just like you would use for weighing something with a load cell. The solution? A load-cell ADC chip, the HX711, found in every cheap scale or online for under a buck. The only other trick was finding a low-voltage pressure sensor to work with it, but that turns out to be easy as well, and I had one delivered in two days.

In all, this project took months of foot-dragging, but only a few clicks and five minutes of soldering once I got the right idea. The industrial applications and manufacturers’ app notes all make sense if you are making hundreds or millions of these devices, where the one-time cost of prototyping up the hard bits gets amortized, but the hacker solution of using a weight-scale chip was just the ticket for a one-off. That just goes to show how useful sharing our tips and tricks can be — you won’t get this from the industry. So send us your success stories, and your useful failures too, and Read More Hackaday!

Pick Up The Ball And Run With It

Once in a while we get to glimpse how people build on each other’s work in unexpected and interesting ways. So it is with the GateBoy project, a gate-level emulator built from die shots of the original Game Boy processor. The thing is, [Austin Appleby] didn’t have to start by decapping and taking photos of the chip. He didn’t even have to make his own schematics by reverse engineering those structures. Someone else had already done that and made it available for others to use. A couple of years back, [Furrtek] started manually tracing out the DMG chip and posted schematics to the DMG-CPU-Inside repo, kindly licensing it as CC-BY-SA 4.0 to let people know how they can use the info.

But playing Game Boy games isn’t actually the end game of [Austin’s] meticulous gate-level recreation. He’s using it to build “a set of programming tools that can bridge between the C/C++ universe used by software and the Verilog/VHDL universe used by hardware.” A new tool has been born, not for gaming, but for converting a meta language that assigns four-letter codes to gate structures (somewhat reminiscent of DNA sequences) and will eventually convert them to your choice of C++ or a Hardware Description Language for use with FPGAs.

The open source community is playing four-dimensional football. Each project moves the ball downfield, but some of them add an additional goal in an alternate hardware universe — advancing the aims of both (like finding and fixing some errors in [Furrtek’s] original schematics).

Of course the real challenge is getting the word out that these projects exist and can be useful for something you’re working on. For instance, [Neumi’s] depth sounding rowboat allows an individual to make detailed depth maps of lakes, rivers, and the like. It was in the comments that the OpenSeaMap project was brought up — a site working to create crowd sourced waterway charts. It’s the perfect place for [Neumi] to get inspiration, and help move that ball toward a set of goals.

How do we get the word out so more of these connections happen? We’ll do our part here at Hackaday. But it’s the well-document and thoughtfully-licensed projects that set the up playing field in the first place.

99% Inspiration, 99% Perspiration, And 99% Collaboration

I was watching an oldish TEDx talk with Rodney Mullen, probably the most innovative street skater ever, but that’s not the point, and it’s not his best talk either. Along the way, he makes a claim that ideas — in particular the idea that a particular skateboard trick is even possible — are the most important thing.

His experience, travelling around the world on skateboard tours, is that there are millions of kids who are talented enough that when they see a video demonstrating that a particular trick idea is possible, they can replicate it in short order. Not because the video showed them how, but because it expanded their mind’s-eye view of what is possible. They were primed, and so what pushed them over the edge was the inspiration.

On the other side of the street, we’ve got Thomas Edison and his “1% inspiration, 99% perspiration” routine. Edison famously tried a bazillion filament recipes before settling on tungsten, and attributes his success to “putting his time in” or “good old-fashioned hard work” or similar. So who’s right?

The inventor of Casper Slide and the phonograph are both right. Rodney is taking it for granted that these kids have put their time in; they are skaters after all, they skate. He doesn’t see the 99% perspiration because it is the natural background, while the inspiration flashes out in Eureka moments.

Similarly, Thomas E. way underestimates inspiration. He’s already fixated on this novel idea to take an arc lamp and contain it in a glass envelope — that’s what he’s spending all of his perspiration on, after all. But without that key inspiration, all he’d be is sweaty.

And they’re also both wrong! They’re both missing a third ingredient: collaboration. Certainly Mullen, who spent his life hanging out with other skaters, teaching them what he knows, and learning from them in turn, wouldn’t say the community of skaters didn’t shape him. Even in the loner’s sport of skating, nobody is alone. And Edison? His company profited greatly from broader advances in science, and the scientific literature. Menlo Park existed to take bright, well-trained minds and put them all in one place, sharing, teaching, and working together. It embodied the idea of collaborative innovation, and that’s where some of his best work was done.

So I’m with Isaac Newton, “standing on the shoulders of giants“. Success is 99% collaboration. This leaves us with one problem: the percentages don’t add up. But that’s alright by me.

Printing Yoda Heads: Re-Makers Riffing!

We had a comment recently from a nasty little troll (gasp! on the Internet!). The claim was that most makers are really just “copiers” because they’re not doing original work, whatever that would mean, but instead just re-making projects that other people have already done. People who print other peoples’ 3D models, or use other peoples’ hardware or software modules are necessarily not being creative. Debunking a cheap troll isn’t enough because, on deeper reflection, I’m guilty of the same generic sentiment; that feeling that copying other people’s work isn’t as worthy as making your own. And I think that’s wrong!

In the 3D printing world in particular, I’m guilty of dismissively classifying projects as “Yoda Heads”. About ten years ago, [chylld] uploaded a clean, high-res model of Yoda to Thingiverse, and everyone printed it out. Heck, my wife still has hers on her desk; and alone this is proof that straight-up copying has worth, because it made a sweet little gift. After a while, Yoda gave way to Baby Groots, and strangely enough we’re back to Yoda again, but it’s Baby Yoda now. Continue reading “Printing Yoda Heads: Re-Makers Riffing!”

Why You Need To Finish

Mike and I were talking about an interesting smart-glasses hack on the podcast. This was one of those projects where, even if you don’t need a pair of glasses with LEDs on them to help you navigate around, you just couldn’t help but marvel at a lot of the little design choices made throughout.

For instance, I love the way the flex PCB is made to do double duty by wrapping around the battery and forming a battery holder. This struck me as one of those quintessential hacks that only occurs to you because you need it. Necessity is the mother of invention, and all that. There was a problem, how to fit a battery holder in the tiny space, and a set of resources that included a flex PCB substrate. Cleverly mashing that all together ended up with a novel solution. This wouldn’t occur to you if you were just sitting at the beach; you’d have to be designing something electronic, space-constrained, and on a flex PCB to come up with this.

Mike made an offhand comment about how sometimes you just need to finish a project for the good ideas and clever solutions that you’ll come up with along the way, and I think this battery holder example drives that point home. I can’t count the number of my projects that may or may not have been dumb in retrospect, but along the way I came up with a little trick that I’ll end up using in many further projects, outliving the original application.

Finishing up a project on principle is a reasonable goal just on its own. But when the process of seeing something to conclusion is the generator of new and interesting challenges and solutions, it’s even more valuable. So if you’re stuck on a project, and not sure you want to take it all the way, consider if the journey itself could be the destination, and look at it as an opportunity to come up with that next long-lasting trick.

Bad News: Arecibo

If you read the newsletter last week, you heard me wondering aloud if the damage to Arecibo Observatory had crossed the threshold into where it’s no longer economically viable to keep it running, and the sad news has just come in and the battle for Arecibo has been lost. We said we’d shed a tear, and here we are. Sic transit gloria mundi. Here’s hoping something cooler replaces it!