Wouldn’t it be nice if every webcam had a hardware switch? Especially for those built-in webcams like the one in your laptop. Since they don’t have switches yet, we’re just stuck trying to remember to turn them off or re-apply the sticker after every meeting. [Becky Stern] was tired of trying to remember to blind the all-seeing eye, and decided to make a robot companion that would do it for her.
Essentially, a servo-driven, 3D-printed eyelid covers the eye’s iris and also the web cam directly underneath. At first, we though [Becky] had liberated the business parts of a cheap webcam and built it into the eyeball, but this is far less intrusive. The eyeball simply sits atop the monitor, and [Becky] can control the eyelid two ways: she can set a timer with the potentiometer to close it automatically after some number of minutes, or else do it on demand using the momentary button. We’d love to see it tied directly to Zoom and or whatever else [Becky] uses regularly. Be sure to check out the build and demo video after the break to see it in action.
If you’re looking for a quick and easy way to control a few devices from your computer, a cheap USB relay board might be the ideal solution. These are fairly simple gadgets, consisting of little more than a microcontroller and a handful of relays. But that doesn’t mean there isn’t room for improvement, and as [Michał Słomkowski] recently demonstrated, flashing these boards with a custom firmware allows the user to modify their default functionality.
In his case, [Michał] wanted to build a power strip that would cut the power to any devices plugged into it once his computer went to sleep. Unfortunately, he couldn’t just check to see if there was 5 V on the line as his motherboard kept the USB ports powered up all the time. But with some modifications to the relay board’s firmware, he reasoned he should be able to detect if there was any USB activity by watching for the start-of-frame packet that goes out every millisecond when the bus is active.
Wiring up the ATtiny45 for flashing.
Now [Michał] isn’t claiming to be the first person to come up with a custom firmware for one of these boards, in fact, he credits an existing open source firmware project as an inspiration for his work. But he did create an entirely new GPLv3 firmware for these ATtiny45 powered devices, which includes among other improvements the latest version of V-USB. As it so happens, V-USB includes start-of-frame packet detection out of the box, which made it much easier to implement his activity detection code.
With the new firmware flashed to the relay board’s chip, [Michał] put it in an enclosure and wired up the outlets. But there was still one missing piece of the puzzle. It seems that Linux won’t actually send out the start-of-frame packets unless its actively communicating with a USB device, as part of the so-called “selective suspend” power saving feature. Luckily there is support for disabling this feature for specific devices based on their Vendor/Product ID pair, so after a little udev fiddling, everything was working as expected.
We’ll just go ahead and say it right up front: we love teardowns. Ripping into old gear and seeing how engineers solved problems — or didn’t — is endlessly fascinating, even for everyday devices like printers and radios. But where teardowns really get interesting is when the target is something so odd and so specialized that you wouldn’t normally expect to get a peek at the outside, let alone tramp through its guts.
[Mads Barnkob] happened upon one such item, a Fujifilm FCR XG-1 digital radiography scanner. The once expensive and still very heavy piece of medical equipment was sort of a “digital film system” that a practitioner could use to replace the old-fashioned silver-based films used in radiography, without going all-in on a completely new digital X-ray suite. It’s a complex piece of equipment, the engineering of which yields a lot of extremely interesting details.
The video below is the third part of [Mads]’ series, where he zeroes in on the object of his desire: the machine’s photomultiplier tube. The stuff that surrounds the tube, though, is the real star, at least to us; that bent acrylic light pipe alone is worth the price of admission. Previous videos focused on the laser scanner unit inside the machine, as well as the mechatronics needed to transport the imaging plates and scan them. The video below also shows experiments with the PM tube, which when coupled with a block of scintillating plastic worked as a great radiation detector.
Ask any electronics hobbyist or professional what the simplest building blocks of electronic circuits are, and they’ll undoubtedly say resistors, capacitors, and inductors. Ask a mechanically-inclined person the same question about their field and the answer will probably be less straightforward. Springs would make the list for sure, but then… hmm. Maybe gears? 80/20 aluminum extrusions?
As it turns out, there are a handful of fundamental building blocks in the mechanisms world, and they’re functionally very similar, and mathematically identical, to the Big Three found in electrical engineering.
Mechanical Equivalents
Before we look at the components themselves, let’s step back a moment and think about voltage and current. Voltage is a potential difference between two points in a circuit, sometimes called electromotive force (EMF). It turns out that EMF is an apt term for it, because it is roughly analogous to, well, force. Voltage describes how “hard” electrons are being “pushed” in a circuit. In much the same vein, current describes the rate of electric charge flow. Continue reading “Building Blocks: Relating Mechanical Elements To Electronic Components”→
You sure do learn a lot when life suddenly makes it impossible to go into the office and asks that you instead do the same work remotely. Sure, there are the obvious challenges like needing a device to do the work on and an internet connection that’s not going to melt down when family or roommates are trying to Zoom at the same time as you one-on-one with the boss. But there’s way more to it. The Refresh Work-From-Home Life challenge takes this on as the next phase of the Hackaday Prize gets under way this morning.
If the global pandemic caused you to find yourself working from home, I’m sure it’s been quite a ride. Maybe you learned what your spine feels like after hunching over a MacBook in bed for 40 hours. Others discovered that the commute had been silently serving as a power-down sequence for your “work brain” — without it you never stopped thinking about, or more likely worrying about, work. And without that change in venue, it’s far too easy to feel like you were now living at work. So let’s invent the things that can make us productive from home while maintaining physical health and preserving our sanity.
Ten entries in this challenge will be awarded with $500 and ushered into the final round where the grand prize of $25,000 and four other top prizes await. What kind of things are we looking for? The best ideas are the ones we haven’t had yet, but I can spitball a bit to get things rolling.
Mirror with a bracket turns a laptop webcam into an overhead project for Zoom classrooms
Furniture and other infrastructure can be a real sore-spot when not a good fit. We’d love to see your design that uses a single sheet of plywood (I know, those cost a bazillion dollars these days but just go with it) to build an adjustable workspace that fits your chair height and needs. Bonus points for one that folds away at quitting time to reassure you that work is done!
Office interruptions from co-works sometimes feel like a distraction. But without them you might not get your body moving for hours on end… not good for you! Design an assistant that watches for your poor sedentary habits and sasses you until you take some time to stretch your old bones. Or show off the gadgets that make living the digital nomad life easier like the awesome document camera hacks we saw from teachers when classrooms were closed last year.
Show off your proof of concept by starting a project page on Hackaday.io and using the dropdown in the left sidebar to enter it into the 2021 Hackaday Prize. You can continue to update it until judging begins at the end of July.
We’re already living in the future. Working or learning remotely is a big part of that. Let’s bend our homes and our habits to find a better way to do it!
Voice controlled home assistants are the wonder of our age, once you’ve made peace with the privacy concerns of sharing the intimacies of your life with a data centre owned by a massive corporation, anyway. They provide a taste of how the future was supposed to be in those optimistic predictions of decades past: Alexa and Siri can crack jokes, control your lights, answer questions, tell you the news, and so much more.
But for all their electronic conversational perfection, your electronic pals can’t satisfy your most fundamental needs and bring you a beer. This is something [luisengineering] has fixed, an he’s provided the appropriate answer to the question “Alexa: bring mir ein bier!“. The video which we’ve also put below the break is in German with YouTube’s automatic closed captions if you want them, but we think you’ll be able to get the point of it if not all his jokes without needing to learn to speak a bit of Deutsch.
As he develops his beer-delivery system we begin to appreciate that what might seem to be a relatively straightforward task is anything but. He takes an off-the-shelf robot and gives it a beer-bottle grabber and ice hopper, but the path from fridge to sofa still needs a little work. The eventual solution involves a lot of trial and error, and a black line on the floor for the ‘bot to follow. Finally, his electronic friend can bring him a beer!
We like [Luis]’s entertaining presentational style, and the use of props as microphone stands. We’ll be keeping an eye out for what he does next, and you should too. Meanwhile it may not surprise you that this is not the first beer-delivery ‘bot we’ve brought you.
There is no question that poaching has become an existential threat to the five species of rhinoceros alive today. Even the wildlife reserves where most rhinos live struggle to provide protection from the wanton and cruel poaching of the world’s last remaining rhinos.
Poachers are generally looking to sell the horns which consist of pure keratin, the same material that makes up our fingernails and hair. Rhino horns have seen a big rise in demand the past decades, with a black market in Vietnam representing the biggest buyers, primarily for use in fever and other medicines, as well as for processing into carved trinkets. This has contributed to a further rhino population collapse. Statistics from 2017 show about 18,000 white rhinos and fewer than 5,500 black rhinos remaining. Recently, the northern white rhino population in Africa went effectively extinct with the death of the last known male individual.
Clearly, if we wish to prevent extinction, we need to deal with poaching. The latest suggestion here is part of the Rhisotope project. This would make rhino horns radioactive, but how exactly would doing so prevent poaching? Let’s take a look.
