One Project At A Time, Or A Dozen?

February 10, 2024 by Elliot Williams 34 Comments

We got a bunch of great food for thought in this week’s ask-us-anything on the Hackaday Podcast, and we all chewed happily. Some of my favorite answers came out of the question about how many projects we all take on at once. Without an exception, the answer was “many”. And while not every one of the projects that we currently have started will eventually reach the finish line, that’s entirely different from saying that none of them ever do. On the contrary, Tom Nardi made the case for having a number of irons simultaneously in the fire.

We all get stuck from time to time. That’s just the nature of the beast. The question is whether you knuckle down and try to brute-force power your way through the difficulty, or whether you work around it. A lot of the time, and this was Dan Maloney’s biggest bugaboo, you lack the particular part or component that you had in mind to get the job done. In that situation, sometimes you just have to wait. And what are you going to do while waiting? Work on Project B! (But take good notes of the state of Project A, because that makes it a lot easier to get back into the swing of things when the parts do arrive.)

Al and I both weighed in on the side of necessity, though. Sometimes, no matter how many attractive other projects you’ve got piled up, one just needs to get out the door first. My recent example was our coffee roaster. Before I start a big overhaul, I usually roast a couple days’ worth of the evil bean. And then the clock starts ticking. No roasting equals two unhappy adults in this household, so it’s really not an option. Time pressure like that helps focus the mind on the top-priority project.

But I’m also with Tom. It’s a tremendous luxury to have a handful of projects in process, and be able to hack on one simply because you’re inspired, or in love with the project at that moment. And when the muse calls, the parts arrive, or you finally figure out what was blocking you on Project A, then you can always get back to it.

In Defense Of Anthropomorphizing Technology

February 7, 2024 by Dan Maloney 56 Comments

Last week I was sitting in a waiting room when the news came across my phone that Ingenuity, the helicopter that NASA put on Mars three years ago, would fly no more. The news hit me hard, and I moaned when I saw the headline; my wife, sitting next to me, thought for sure that my utterance meant someone had died. While she wasn’t quite right, she wasn’t wrong either, at least in my mind.

As soon as I got back to my desk I wrote up a short article on the end of Ingenuity‘s tenure as the only off-Earth flying machine — we like to have our readers hear news like this from Hackaday first if at all possible. To my surprise, a fair number of the comments that the article generated seemed to decry the anthropomorphization of technology in general and Ingenuity in particular, with undue harshness directed at what some deemed the overly emotional response by some of the NASA/JPL team members.

Granted, some of the goodbyes in that video are a little cringe, but still, as someone who seems to easily and eagerly form attachments to technology, the disdain for an emotional response to the loss of Ingenuity perplexed me. That got me thinking about what role anthropomorphization might play in our relationship with technology, and see if there’s maybe a reason — or at least a plausible excuse — for my emotional response to the demise of a machine.

Continue reading “In Defense Of Anthropomorphizing Technology” →

You Can’t Make What You Can’t Measure

December 16, 2023 by Elliot Williams 30 Comments

What’s the most-used tool on your bench? For me, it’s probably a multimeter, although that’s maybe a tie with my oscilloscope. Maybe after that, the soldering iron and wire strippers, or my favorite forceps. Calipers must rate in there somewhere too, but maybe a little further down. Still, the top place, and half of my desert-island top-10, go to measuring gear.

That’s because any debugging, investigation, or experimentation always starts with getting some visibility on the problem. And the less visible the physical quantity, the more necessary to tool. For circuits, that means figuring out where all the voltages lie, and you obviously can’t just guess there. A couple months ago, I was doing some epoxy and fiberglass work, and needed to draw a 1/2 atmosphere vacuum. That’s not the kind of quantity you can just eyeball. You need the right measurement tool.

A few weeks ago, I wrote about my disappointment in receiving a fan that wouldn’t push my coffee beans around in the homemade roaster. How could I have avoided this debacle? By figuring out the pressure differential needed and buying a fan that’s appropriately rated. But I lacked pressure and flow meters.

Now that I think about it, I could have scavenged the pressure meter from the fiberglassing rig, and given that a go, but with the cheap cost of sensors and amplifiers, I’ll probably just purpose-build something. I’m still not sure how I’ll measure the flow; maybe I’ll just cheese out and buy a cheap wind-speed meter.

When people think of tools, they mostly think of the “doers”: the wrenches and the hammers of this world. But today, let’s all raise a calibrated 350 ml glass to the “measurers”. Without you, we’d be wandering around in the dark.

Degrees Of Freedom, But For Whom?

December 9, 2023 by Elliot Williams 48 Comments

Opening up this week’s podcast, I told Kristina about my saga repairing our German toilet valve. I’m American, and although I’ve lived here over a decade, it’s still surprising how things can be subtly different from how they worked back home.

But what was amazing about this device was that it had a provision for fine adjustment, and to some extent relied on this adjustment to function. Short version: a lever mechanism provides mechanical advantage to push a stopper against the end of a pipe to block the water flow, and getting the throw of this mechanism properly adjusted so that the floater put maximum pressure against the pipe required fine-tuning with a screw. But it also required understanding the entire mechanism to adjust it.

Which makes me wonder how many plumbers out there actually take the time to get that right. Are there explicit instructions in the manual? Does every German plumber learn this in school? I was entirely happy to have found the adjustment screw after I spent 15 minutes trying to understand the mechanism, because it did just the trick. But is this everyone’s experience?

I often think about this when writing code, or making projects that other people are likely to use. Who is the audience? Is it people who are willing to take the time to understand the system? Then you can offer them a screw to turn, and they’ll appreciate it. But if it’s an audience that just doesn’t want to be bothered, the extra complexity is just as likely to cause confusion and frustration.

The Physics Lesson I Keep Re-Learning

December 2, 2023 by Elliot Williams 69 Comments

One of the most broadly applicable ideas I’ve ever encountered is the concept of impedance matching. If you’re into radio frequency electronics, you’re probably thinking that I mean getting all your circuit elements working to a common characteristic resistance for maximum power transfer. (If you’re not, you’re probably wondering what that jumble of words even means. Fear not!)

But I mean impedance matching in the larger sense. Think about driving a stick-shift automobile. In low gear, the engine has a lot of torque on the wheels, but it can’t spin them all that fast. In high, the wheels turn fastest, but there’s not enough torque to get you started from a standstill. Sometimes you need more force and less motion, other times more motion and less force. The gearbox lets you match the motor’s power to the resistance – the impedance – it’s trying to overcome.

Or think about a cello. The strings are tight, and vibrate with quite a bit of force, but they don’t move all that much. Air, which is destined to carry the sound to your ear, doesn’t take much force to move, and the cello would play louder if it moved more of it. So the bridge conveys the small, but strong, vibrations of the strings and pushes against the top of the resonant box that makes up the body of the instrument. This in turn pushes a lot of air, but not very hard. This is also why speakers have cones, and also why your ear has that crazy stirrup mechanism. Indeed, counting the number of impedance matches between Yo Yo Ma and your brain, I come up with four or five, including electrical matches in the pre-amp.

I mention this because I recently ran into a mismatch. Fans blow air either hard or in large volume. If you pick a fan that’s designed for volume, and put it in a pressure application, it’s like trying to start driving in fifth gear. It stalled, and almost no air got pushed up through the beans in my new “improved” coffee roaster, meaning I had to rebuild it with the old fan, and quick before the next cup was due.

I ran into this mismatch even though I knew there was a possible impedance issue there. I simply don’t have a good intuitive feel how much pressure I needed to push the beans around – the impedance in question – and I bought the wrong fan. But still, knowing that there is a trade-off is a good start. I hope this helps you avoid walking in my footsteps!

Blinded With Science

August 12, 2023 by Elliot Williams 62 Comments

So the room-temperature superconductor was a super disappointment, but even though the claims didn’t stand up in the end, the even better news is that real science was done. A paper making extraordinary claims came out, the procedure to make LK-99 was followed in multiple labs around the world, and then it was tested. It didn’t turn out to conduct particularly well at all. After a couple weeks of global superconductor frenzy, everything is back to normal again.

What the heck happened? First of all, the paper itself made extravagant claims about a holy-grail kind of material. There was a very tantalizing image of a black pellet floating in mid air, which certainly seems like magic, even though it’s probably only run-of-the-mill ferromagnetism in the end. But it made for a great photo-op in a news-starved August, and the then-still-Twitterverse took to it by storm. And then the news outlets piled on the hype fest.

If you’re feeling duped by the whole turn of events, you’re not alone. But the warning signs were there from the beginning, if you took the time to look. For me, it was the closing line of the paper: “We believe that our new development will be a brand-new historical event that opens a new era for humankind.”

That’s not the kind of healthy skepticism and cautious conclusion that real science runs best on. Reading the paper, I had almost no understanding of the underlying materials science, but I knew enough about human nature to suspect that the authors had rushed the paper out the door without sufficient scrutiny.

How can we keep from being fooled again? Carl Sagan’s maxim that “extraordinary claims require extraordinary evidence” is a good start. To that, I would add that science moves slowly, and that extraordinary evidence can only accumulate over time. So when you see hype science, simply wait to draw any conclusions. If it is the dawn of a new era, you’ll have a lot of time to figure out what room-temperature superconductivity means to you in the rosy future. And if it’s just a flash in the pan, you won’t have gotten your hopes up.

Brainstorming

November 19, 2022 by Elliot Williams 5 Comments

One of the best things about hanging out with other hackers is the freewheeling brainstorming sessions that tend to occur. Case in point: I was at the Electronica trade fair and ended up hanging out with [Stephen Hawes] and [Lucian Chapar], two of the folks behind the LumenPnP open-source pick and place machine that we’ve covered a fair number of times in the past.

Among many cool features, it has a camera mounted on the parts-moving head to find the fiducial markings on the PCB. But of course, this mean a camera mounted to an almost general purpose two-axis gantry, and that sent the geeks’ minds spinning. [Stephen] was talking about how easy it would be to turn into a photo-stitching macrophotography rig, which could yield amazingly high resolution photos.

Meanwhile [Lucian] and I were thinking about how similar this gantry was to a 3D printer, and [Lucian] asked why 3D printers don’t come with cameras mounted on the hot ends. He’d even shopped this idea around at the East Coast Reprap Festival and gotten some people excited about it.

So here’s the idea: computer vision near extruder gives you real-time process control. You could use it to home the nozzle in Z. You could use it to tell when the filament has run out, or the steppers have skipped steps. If you had it really refined, you could use it to compensate other printing defects. In short, it would be a simple hardware addition that would open up a universe of computer-vision software improvements, and best of all, it’s easy enough for the home gamer to do – you’d probably only need a 3D printer.

Now I’ve shared the brainstorm with you. Hope it inspires some DIY 3DP innovation, or at least encourages you to brainstorm along below.