An elderly relative of mine used to get irate at the BBC news. When our Prime Minister [Edward Heath] or another of her bêtes noirs of the day came on, she’d rail at the radio or the TV, expressing her views to them in no uncertain terms. It taught a young me a lot about the futility of shouting at the telly, as well as about making a spectacle of oneself.
The ISS in flight. NASA [Public domain].The other evening though I found myself almost at the point of shouting at a TV programme, and since it’s one with a clear message about technology I feel it’s worth sharing here. The programme in question was one of the Impossible Engineering series, and it was talking about the technology behind the International Space Station. It was recent enough to include last year’s mission involving [Tim Peake], so it was by no means a show dredged from the archives.
All very well, you say. Impossible Engineering‘s format of looking at a modern engineering marvel and tracing the historical roots of some of its innovations would find fertile ground in the ISS, after all it’s one of our most impressive achievements and could easily provide content for several seasons of the show. And I’ll give them this, they did provide an interesting episode.
The trouble was, they made an omission. And it wasn’t just a slight omission, one of those minor cock-ups that when we Hackaday scribes make them the commenters pounce upon with glee, this one was a doozy. They managed to fill an hour of television talking about space stations and in particular a space station that was assembled by multiple countries under an international co-operation, without mention of any of the Russian technology that underpins much of its design. An egregious example among many was their featuring a new Boeing capsule designed to touchdown on land rather than on water as a novel invention, when as far as I am aware every Russian capsule ever made has performed a land-based touchdown.
Life is good if you are a couch potato music enthusiast. Bluetooth audio allows the playing of all your music from your smartphone, and apps to control your hi-fi give you complete control over your listening experience.
Not quite so for [Daniel Landau] though. His Cambridge Audio amplifier isn’t quite the latest generation, and he didn’t possess a handy way to turn it on and off without resorting to its infrared remote control. It has a proprietary interface of some kind, but nothing wireless to which he could talk from his mobile device.
His solution is fairly straightforward, which in itself says something about the technology available to us in the hardware world these days. He took a Raspberry Pi with the Home Assistant home automation package and the LIRC infrared subsystem installed, and had it drive an infrared LED within range of the amplifier’s receiver. Coupled with the Home Assistant app, he was then able to turn the amplifier on and off as desired. It’s a fairly simple use of the software in question, but this is the type of project upon which so much more can later be built.
Not so many years ago this comparatively easy project would have required a significant amount more hardware and effort. A few weeks ago [John Baichtal] took a look at the evolution of home automation technology, through the lens of the language surrounding the term itself.
There was a time when crowdfunding websites were full of 3D printers at impossibly low prices. You knew that it would turn out to be either blatant vaporware or its delivery date would slip into the 2020s, but still there seemed always to be an eager queue ready to sign up. Even though there were promised models for under $200, $150, and then $100, there had to be a lower limit to the prices they were prepared to claim for their products. A $10 printer on Kickstarter for example would have been just a step too far.
There is a project that’s come close to that mark though, even though the magic figure is 10 euros rather than 10 dollars, so just short of 12 dollars at today’s exchange rate. [Michele Lizzit] has built a functioning 3D printer for himself, and claims that magic 10€ build price. How on earth has he done it? The answer lies in extensive use of scrap components, in this case from broken inkjet printers and an image scanner. These provide all the mechanical parts for the printer, leaving him only having to spend his 10€ on some hot end parts and the printer’s electronics. In an unusual move, the frame of the machine appears to come from a set of cardboard biscuit boxes, a master stroke of junk box construction.
The claimed resolution is 33µm, and using the position encoders from the inkjet printers he is able to make it a closed loop device. We salute his ingenuity in building such an impressive printer from so little, and were we ever locked by the bad guys in a room full of IT junk and lacked a handy escape device, we’d wish to be incarcerated with [Michele] any day over [Angus MacGyver] or [Sgt. Bosco BA Baracus].
You can see the printer in action in the video below the break.
When a friend finds her caravan’s deep-cycle battery manager has expired over the summer, and her holiday home on wheels is without its lighting and water pump, what can you do? Faced with a dead battery with a low terminal voltage in your workshop, check its electrolyte level, hook it up to a constant current supply set at a few hundred mA, and leave it for a few days to slowly bring it up before giving it a proper charge. It probably won’t help her much beyond the outing immediately in hand, but it’s better than nothing.
A lot of us will own a lead-acid battery in our cars without ever giving it much thought. The alternator keeps it topped up, and every few years it needs replacing. Just another consumable, like tyres or brake pads. But there’s a bit more to these cells than that, and a bit of care and reading around the subject can both extend their lives in use and help bring back some of them after they have to all intents and purposes expired.
One problem in particular is sulphation of the lead plates, the build-up of insoluble lead sulphate on them which increases the internal resistance and efficiency of the cell to the point at which it becomes unusable. The sulphate can be removed with a high voltage, but at the expense of a dangerous time with a boiling battery spewing sulphuric acid and lead salts. The solution therefore proposed is to pulse it with higher voltage spikes over and above charging at its healthy voltage, thus providing the extra kick required to shift the sulphation build up without boiling the electrolyte.
If you read around the web, there are numerous miracle cures for lead-acid batteries to be found. Some suggest adding epsom salts, others alum, and there are even people who talk about reversing the charge polarity for a while (but not in a Star Trek sense, sadly). You can even buy commercial products, little tablets that you drop in the top of each cell. The problem is, they all have the air of those YouTube videos promising miracle free energy from magnets about them, long on promise and short on credible demonstrations. Our skeptic radar pings when people bring resonances into discussions like these.
There are times in everybody’s life when they feel the need to shoot at things in a harmless manner. For those moments there are rubber bands and Nerf darts, but even then they feel like mere toys. If that is the point at which you find yourself, then maybe [Austin]’s home-made electric disc shooter can help.
Operation of the shooter is simple enough. A stack of 3D-printed plastic discs is loaded into a tubular magazine, from which individual disks are nudged by a motor-driven cam controlled by the trigger. Once the disc leaves the magazine it reaches a vacuum cleaner belt driven by a much more powerful motor, that accelerates the disc to ejection velocity.
The video below the break shows the gun’s construction, as well as a sequence involving the destruction of plenty of balloons, soda cans, and food items. The 3D-printed ammunition seems to us to be the weak link as in our experience it is inevitable that there is a high ammunition loss rate with these type of weapons, but maybe [Austin] has a line on some cheap filament. Either way, his disc gun looks like the kind of toy that could provide an entertaining diversion for many readers.
There are a series of stages to coming down from a festival. After the hectic rush of travel there are the several days of catching up on lost sleep and picking up the threads of your life again, then once a semblance of order has been regained there’s that few weeks of emptiness. Your life will never be the same again, it’s all so mundane.
I’m pleased to say the Hackaday and Tindie stickers were very popular.
It’s now a couple of weeks since the SHACamp 2017 hacker festival in the Netherlands was in full swing, and the write-up below has slowly taken shape over that time amid the other work of being a Hackaday scribe and editor. It’s early morning here in Southern England as I write this, so on the equivalent day while I was at SHACamp at this time I would have been carrying a large pack of stickers for distribution on the swapping table through the rising sunlight of a camp still largely asleep after the previous night’s revelry. Past our German and Dutch immediate neighbours, down the ramp from the dyke, the cardboard tent depot on my left and the food court on my right, to the information tent. Greet the bleary-eyed volunteer at the end of their graveyard shift, and spread plenty of Hackaday and Tindie stickers on the table for the masses. And then? Find a coffee, and sally forth into the field for another day among one of the most stimulating communities on Earth. My community. Your community.
The sticker table is a good place to start if you wish to get a handle on a large hacker camp. On it you will find the logos of a cross-section of the diverse organisations and groups present. There are a few commercial ones like my Jolly Wrenchers and Tindie the puppy, there are some from voluntary organisations or interest groups, but mostly they are the logos of a continent’s — even the wider world’s in some cases — hackspaces and makerspaces. Here you see the breadth of the attendees, as the logos of spaces from thousands of miles away you’ve never encountered before mingle. This isn’t quite a global gathering, but there is a sense of global community around it.
How Do You Describe a Hacker Camp?
You shall find us by our clearly superior yet dangerous to barefoot pedestrians fused right-angled mains connector.
So before I take you through my experience of SHA, it’s best to start by describing a hacker camp in more general terms. When I’m describing a camp like SHA to the kind of people who don’t read Hackaday, I put it as similar to the music festivals they are used to but without the bands. Instead the audience provides the entertainment through the work they bring to the event or do at the event, and through a comprehensive program of talks and lectures. Oh — and this is the bit that makes their eyes open wide — every structure on site from the smallest one-man tent to the largest marquee has mains power and high-speed Internet. Sometimes people grasp what SHA is from this description, sometimes they don’t.
Different groups, be they individual hackspaces, people from a particular country, or other special interest groups, congregate in villages, collections of tents, marquees, and gazebos in which they set up whatever cool stuff they’ve brought along. My tent with its Hackaday flag was in a village composed of a mix of British hackspaces up on the dyke, which [Michael] from MK Makerspace had marked with a sign consisting of a huge BS1363A mains plug. More than one person pointed out it would have been better lying flat on the ground with pins in the air, ready to catch an unwary Monty Python foot.
There was a third-party multiplayer upgrade pack for one of the Quake games back in the ’90s that included a whole slew of non-standard weapons. Among them one of the most memorable was a gravity well, that when thrown into the middle of a crowded room full of warring players would suck them into a vortex. Assuming its user had made it to safety in time, they would then be left the victor. The hyper-violent make-believe world of a first-person shooter is probably best left in a Pentium server from the ’90s, with few direct parallels in the real world. Maybe laser tag, or Nerf battles, are the closest you’ll get.
If you are a Nerf enthusiast, then you’ll appreciate [Giaco Whatever]’s CO2-powered remote-control Nerf bomb as an analogue of that Quake gravity well. It fires twelve darts at the press of a button on an infra-red remote control. The firing tubes sit in a nicely machined manifold connected via a solenoid valve to a little CO2 gas bottle. In the hectic world of a Nerf war it is slid out into the field of combat, its operator takes cover, and the other participants are showered in foam darts. There are probably kids who would sell their grandparents to own this device.
The build is detailed in the video below the break, along with a wonderfully tongue-in-cheek movie segment demonstrating it in action.
