The Tiny, Pocket-Sized Robot Meant For Hacking

The world is full of educational robots for STEAM education, but we haven’t seen one as small or as cute as the Skoobot, an entry in this year’s Hackaday Prize. It’s barely bigger than an inch cubed, but it’s still packed with motors, a battery, sensors, and a microcontroller powerful enough to become a pocket-sized sumo robot.

The hardware inside each Skoobot is small, but powerful. The main microcontroller is a Nordic nRF52832, giving this robot an ARM Cortex-M4F brain and Bluetooth. The sensors include a VL6180X time of flight sensor that has a range of about 100mm. Skoobot also includes a light sensor for all your robotic photovoring needs. Other than that, the Skoobot is just about what you would expect, with a serial port, a buzzer, and some tiny wheels mounted in a plastic frame.

The idea behind the Skoobot is to bring robotics to the classroom, introducing kids to fighting/sumo robots, while still being small, cheap, and cute. To that end, the Skoobot is completely controllable via Bluetooth so anyone with a phone, a Pi, or any other hardware can make this robot move, turn, chase after light, or sync multiple Skoobots together for a choreographed dance.

While the Skoobot is an entry for this year’s Hackaday Prize, the creator of the Skoobot, [Bill Weiler] is also making these available on Crowd Supply.

Camera Uses Algorithms Instead Of Lenses

A normal camera uses a lens to bend light so that it hits a sensor. A pinhole camera doesn’t have a lens, but the tiny hole serves the same function. Now two researchers from the University of Utah. have used software to recreate images from scattered unfocused light. The quality isn’t great, but there’s no lens — not even a pinhole — involved. You can see a video, below.

The camera has a sensor on the edge of a piece of a transparent window. The images could resolve .1 line-pairs/mm at a distance of 150 mm and had a depth of field of about 10 mm. This may seem like a solution that needs a problem, but think about the applications where a camera could see through a windshield or a pair of glasses without having a conventional camera in the way.

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String Art Robot Is An Autorouter In Reverse

In the depths of Etsy and Pinterest is a fascinating, if tedious, artform. String art, the process of nailing pins in a board and wrapping thread around the perimeter to create shapes and shading, The most popular project in this vein is something like putting the outline of a heart, in string, in the shape of your home state. Something like that, at least.

While this artform involves about as much effort as pallet wood furniture, there is an interesting computational aspect of it: you can create images with string art, and doing this is a very, very hard problem to solve with an algorithm. Researchers at TU Wien have brought out the best that string art has to offer. They’ve programmed an industrial robot to create portraits out of string.

The experimental setup for this is about as simple as it gets. It’s a circular frame studded with 256 hooks around the perimeter. An industrial robot arm takes a few kilometers of thread winds a piece of string around one of these hooks, then travels to another hook. Repeat that thousands and thousands of times, and you get a portrait of Ada Lovelace or Albert Einstein.

The wire wrapped backplane of a DEC PDP-11. This was assembled by a robot that was programmed with an autorouter. It’s also string art.

The real trick here is the algorithm that takes an image and translates it into the paths the string will take. This is an NP-hard problem, but it is a surprisingly well-studied problem. The first autorouters — the things you should never trust to route traces between the packages on your PCB — we created for wire wrapped computers. Here, computers would find the shortest path between whatever pins had to be connected together. There were, of course, limitations: pins could only have so many connections on them thanks to the nature of wire wrapping, and you couldn’t have one gigantic mass of wires for a parallel bus. The first autorouters were string art algorithms, only in reverse.

You can take a look at the complete publication here.

You’ll also find prior art (tee-hee) in our own pages. Here is an artist doing it by hand, and here’s a machine to do it for you if you’re lazy. We’ve even seen further work on the underlying algorithm on Hackaday.io.

Testing lithium ceramic battery

Testing Lithium Ceramic Batteries (LCBs)

Affordable solid-state batteries large enough for cell phones and drones have been promised for a long time but seem to always be a few years away from production. In this case, Taiwan based Prologium sent [GreatScott] samples of their Lithium Ceramic batteries (LCBs) to test, and even though they’re not yet commercial products, who are we to refuse a peek at what they’ve been up to? They sent him two types, flexible ones (FLCBs) and higher capacity stiff ones (PLCBs).

Flexible lithium ceramic batteryThe FLCBs were rated at 100 mAh and just 2 C, both small values but still useful for wearables, especially given their flexibility. Doing some destructive testing, he managed to keep an LED lit while flexing the battery and cutting away at it with tin snips.

Switching to the thicker 7.31 Wh PLCB, he measured and weighed it to get an energy density of 258 Wh/L and a specific energy of 118 Wh/kg, only about 2/3rds and 1/2 that of his LiPo and lithium-ion batteries. Repeating the destructive tests with these ones, the LED turned off and smoke appeared while cutting and hammering a nail through, likely due to the shorts caused by the electrically conductive tin snips and nail. But once the snips and nail were moved away, the smoke stopped and the LED lit up again. Overcharging and short-circuiting the batteries both caused the solder connecting the wires to them to melt but nothing else happened. Rapidly discharging through a resistor only resulted in a gradual voltage drop. Clearly, these batteries are much safer than their LiPo and lithium ion counterparts. That safety and their flexibility seem to be their current main selling points should they become available for us hackers. Check out his tests in the video below.

Meanwhile, we’ll have to be content with the occasional tantalizing report from the labs such as this one from MIT of a long battery life and another from one of the co-inventors of the lithium-ion battery which uses a glass electrolyte.

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Electromagnetic Field: Speczilla!

It is a golden rule of the journalist’s art, that we report the news, we don’t make it. But just occasionally we find ourselves in the odd position of being in the right place such that one of our throwaway comments or actions has the unintended consequence of seeding a story. This is one of those moments, so it’s a rare case of use of the first person in a daily piece as your scribe instead of Hackaday’s usual second person.

At the SHA2017 hacker camp in the Netherlands, [Matt “Gasman” Westcott] gave his presentation on composing a chiptune from an audience suggestion. Afterwards my Tweet about never having seen a Sinclair Spectrum as large as the one on the presentation screen grew a life of its own and became the idea for a project, which in turn at Electromagnetic Field 2018 was exhibited as a giant-sized fully working Sinclair ZX Spectrum.

Since much of the work was performed in Oxford Hackspace I saw Matt’s progression, his first experiments with foam rubber keys, then as he refined his two-wire switch mechanism. Early experiments hooking a row of them up to a real Spectrum motherboard weren’t the success he’d hoped for, so he moved to the FUSE emulator on a Raspberry Pi. A huge effort and needlework learning curve plus a lot of help from OxHack’s textile specialists and buying his local furniture store’s entire stock of foam allowed him to perfect a facsimile of the classic Spectrum’s case and blue rubber keys, while its lettering and iconic BASIC keywords were vinyl-cut at rLab in Reading. A Milton Keynes Makerspace member provided transport to the camp where it was united with a huge TV in a gazebo, completing the trio of local spaces.

At the camp, though it suffered a few technical hitches along the way it was rather a success. There were two techniques, kneeling down and pressing keys with the palm of your hand, or dancing on them in socked feet for complex manoeuvres. The trademark single-key-press BASIC keywords took a little while to re-learn though, there was a time when those were instinctive.

We’d normally wrap a piece like this one up with a link or two. To other projects perhaps, or other hacks from the same person. But in this case we have neither another home computer on this scale, nor any hacks from [Matt], as he’s well known in the European arm of our community for something completely different. As [Gasman] he’s a chiptune artist par excellence, as you can see if you watch his set from the 2014 Electromagnetic Field.

A Dozen Tubes Make An Educational Amplifier

If you asked [Hans_Daniel] what he learned by building a tube audio amplifier with a dozen tubes that he found, the answer might just be, “don’t wind your own transformers.” We were impressed, though, that he went from not knowing much about tubes to a good looking amplifier build. We also like the name — NASS II-12 which apparently stands for “not a single semiconductor.”

Even the chassis looked really good. We didn’t know textolite was still a thing, but apparently, the retro laminate is still around somewhere. It looks like a high-end audio component and with the tubes proudly on display on the top, it should be a lot of fun to use.

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AI Finds More Space Chatter

Scientists don’t know exactly what fast radio bursts (FRBs) are. What they do know is that they come from a long way away. In fact, one that occurs regularly comes from a galaxy 3 billion light years away. They could form from neutron stars or they could be extraterrestrials phoning home. The other thing is — thanks to machine learning — we now know about a lot more of them. You can see a video from Berkeley, below. and find more technical information, raw data, and [Danielle Futselaar’s] killer project graphic seen above from at their site.

The first FRB came to the attention of [Duncan Lorimer] and [David Narkevic] in 2007 while sifting through data from 2001. These broadband bursts are hard to identify since they last a matter of milliseconds. Researchers at Berkeley trained software using previously known FRBs. They then gave the software 5 hours of recordings of activity from one part of the sky and found 72 previously unknown FRBs.

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