Anti-Gravity, Time Travel, And Teleportation: Dr. Hamming Gives Advice

June 1, 2021 by Al Williams 27 Comments

You may not know the name [Richard Hamming], but you definitely use some of his work. While working for Bell Labs, he developed Hamming codes — the parent of a class of codes that detect, and sometimes correct, errors in everything from error-correcting memory to hard drives. He also worked on the Manhattan Project and was a lecturer at the Naval Postgraduate school.

Turns out [Hamming] has an entire class from the 1990s on YouTube and if you are interested in coding theory or several other topics, you could do worse than watch some of them. However, those videos aren’t what attracted me to the lectures. As the last lecture of his course, [Hamming] used to give a talk called “You and Your Research” and you can see one of the times he delivered it in the video below. You might think that it won’t apply to you because you aren’t a professional academic or researcher, but don’t be too quick to judge.

Turns out, [Hamming’s] advice — even by his own admission — is pretty general purpose for your career or even your life. His premise: As far as we know, you have one life to live, so why shouldn’t it be a worthwhile one by your definition of worthwhile.

Along the way, he has an odd combination of personal philosophy, advice for approaching technical problems, and survival skills for working with others. If you are in the field, you’ll probably recognize at least some of the names he drops and you’ll find some of this technical advice useful. But even if you aren’t, you’ll come away with something. Some of it seems like common sense, but it is different, somehow, to hear it spoken out loud. For example:

If you don’t work on important problems, it’s not likely that you’ll do important work.

One piece of technical advice? Don’t waste time working on problems you have no way to attack. He points out that anti-gravity, time travel, and teleportation would be very lucrative. But why work on them when there appears to be no way to even remotely accomplish them today. Well, at least when he said that. There has been a little progress on a form of teleportation, but that wasn’t what he was talking about anyway.

While not a hack in the traditional sense, examining your life, career, and technical research to improve your own effectiveness is something to take seriously. We were hoping he would throw in a joke about error-correcting your career, but unless we blinked, no such luck.

Hamming’s work on block codes was followed about ten years later by the Reed-Solomon code which is found nearly everywhere now. Hamming is also associated with the term “hamming distance,” something we talked about when discussing Gray code.

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Small Swedish Stores Are Miniature Oases In A National Food Desert

May 30, 2021 by Kristina Panos 47 Comments

It all started one night in 2016 after [Robert Ilijason] dropped the last remaining jar of baby food in the house, breaking it. On the 20-minute drive to the nearest supermarket, he had an idea: what if there were small, 24-hour convenience-level grocery stores that could fill the glaring need for access to basics across the country?

Sweden has lost a few thousand smaller grocery stores in the last 25 years or so, mostly in rural areas. For many people living outside the cities, the nearest place to buy milk is several miles away, at a huge supermarket that’s either in a city, or close to it. After [Robert] built Sweden’s first 24-hour unmanned convenience store, the idea received quite a bit of media attention.

Five years and a pandemic later, the concept is still going strong. A chain of 30 of these bite-sized bodegas have popped up all over Sweden, run by a company called Lifvs. They have no staff at all, not even a cashier. Instead, shoppers unlock the door with their phones. They scan all their barcodes into an app, which provides a bill every month and is linked to both their bank account and national identity system. Beyond that, security is in the form of a single camera.

Because these tiny stores are staff-less, the prices can be kept relatively low. The only problem is that the technology is a bit of an issue for some older residents. Back in 2016, [Robert Ilijason] was trying to figure out another way for customers to unlock the door, but it doesn’t look like Lifvs has solved that problem yet.

One thing you can’t complain about with a store like this is the selection. We have to wonder if shoppers are more or less likely to encounter fasciated fruit amongst the produce.

Spherical Keyboard Build Leaves Hacker Well-Rounded

May 20, 2021 by Kristina Panos 20 Comments

Often times we as hackers don’t know what we’re doing, and we sally forth and do it anyway. Here at Hackaday, we think that’s one of the best ways to go about a new project, and the absolute fastest way to learn a whole lot as you go. Just ask [Aaron Rasmussen] regarding this spherical, standing 5×6 dactyl manuform keyboard build, which you can see in a three-part short video series embedded after the break.

[Aaron] gets right down to it in the first video. He had to get creative right away, slicing up the dactyl manuform model to fit on a tiny print bed. However, there’s plenty of room inside the sphere for all that wiring and a pair of Elite-C microcontrollers running QMK. Be sure to turn on the sound to hear the accompanying voice-overs.

The second video answers our burning question: how exactly does one angle grind a slippery sphere without sacrificing sheen or shine? We love the solution, which involves swaddling the thing in duct tape and foam.

You may be wondering how [Aaron] is gonna use any kind of mouse while standing there at the pedestal keyboard. While there is space for a mouse to balance on top, this question is answered in the third video, where [Aaron] learns the truth behind the iconic ThinkPad nubbin and applies this knowledge to build a force-feedback joystick/trackpoint mouse. Awesome answer, [Aaron]!

Not ready to go full-tilt, sci-fi prop ergo? Dip your toe in the DIY waters with a handy macropad.

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Automated Watering Machine Has What Plants Crave: Fertilizer

May 14, 2021 by Kristina Panos 19 Comments

We’ve seen countless automated plant care systems over the years, but for some reason they almost never involve the secret sauce of gardening — fertilizer. But [xythobuz] knows what’s up. When they moved into their new flat by themselves, it was time to spread out and start growing some plants on the balcony. Before long, the garden was big enough to warrant an automated system for watering and fertilizing.

This clever DIY system is based around a 5L gravity-fed water tank with solenoid control and three [jugs] of liquid fertilizer that is added to the water via peristaltic pump. Don’t worry, the water tank has float switches, and [xythobuz] is there to switch it off manually every time so it doesn’t flood the flat.

On the UI side, an Arduino Nano clone is running the show, providing the LCD output and handling the keypad input. The machine itself is controlled with an ESP32 and a pair of four-channel relay boards that control the inlet valve, the four outlet valves, and the three peristaltic pumps that squirt out the fertilizer. The ESP also serves up a web interface that mimics the control panel and adds in the debug logs. These two boards communicate using I²C over DB-9, because that’s probably what [xythobuz] had lying around. Check out the demo video after the break, and then go check on your own plants. They miss you!

Don’t want to buy just any old peristaltic pumps? Maybe you could print your own.

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Seeing-Eye Shoes Pair Computer Vision With Haptic Feedback

May 12, 2021 by Kristina Panos 21 Comments

Over the years, we’ve seen plenty of projects that use ultrasonic or time-of-flight sensors as object detection methods for the visually impaired. Ultrasonic sensors detect objects like sonar — they send sound pulses and measure the time it takes for the signal to bounce off the object and come back. Time-of-flight sensors do essentially the same thing, but with infrared light. In either case, the notifications often come as haptic feedback on the wrist or head or whatever limb the ultrasonic module is attached to. We often wonder why there aren’t commercially-made shoes that do this, but it turns out there are, and they’re about to get even better.

The shoe’s view — safe walking space is delimited with color. Image via TU Graz

Today, Tec-Innovation makes shoes with ultrasonic sensors on the toes that can detect objects up to four meters away. The wearer is notified of obstacles through haptic feedback in the shoes as well as an audible phone notification via Bluetooth. The company teamed up with the Graz University of Technology in Austria to give the shoes robot vision that provides even better detail.

Ultrasonic is a great help, but it can’t detect the topography of the obstacle and tell a pothole from a rock from a wall. But if you have a camera on both feet, you can use the data to determine obstacle types and notify the user accordingly. These new models will still have the ultrasonic sensors to do the initial object detection, and use the cameras for analysis.

Whenever they do come out, the sensors will all be connected through the app, which paves the way for crowdsourced obstacle maps of various cities. The shoes will also be quite expensive. Can you do the same thing for less? Consider the gauntlet thrown!

We could all use some navigational help sometimes. Don’t want to look like a tourist? Get turn-by-turn directions in the corner of your eye.

Thanks for the tip, [Qes]!

The Coffee Must Flow: Replacing A Spent Lithium Cell In A Coffee Machine

May 11, 2021 by Maya Posch 37 Comments

When [hacky] bought a used Douwe Egberts Gallery 200 all-in-one coffee maker, the machine was known to have a ’empty battery’. Being one of those fancy coffee makers that handle everything from the grinding of coffee beans to the application of hot water and steam, it relies on instructions for each coffee recipe. Unfortunately, it turns out that this machine stores these on battery-backed SRAM, as [hacky] found out with help from friendly folk over at the Dutch Tweakers forum.

The Douwe Egberts Gallery 200 is a rebranded machine that’s also sold in Scandinavia as the Wittenborg FB 5100. These machines have an ST M48T58 TimeKeeper module that combines 8 kB of persistent SRAM with a real-time clock. Being powered from a single coin cell (lithium carbon monofluoride chemistry), their lifespan is limited.

Replacing the coin cell in an M48T58 TimeKeeper module with AA cells.

Fortunatley, a DE-9 connector is provided on the back to provide service/maintenance access to to the hardware. Using a conveniently available programming guide for the hardware, it was easy to figure out the pinout and baud rate (9600, 8 bit, ignore parity, no flow control). This allows for reprogramming the SRAM, but without replacing the battery this data would be gone again on the next start.

Based on the ST M48T58 datasheet, it’s not clear that the clip-on module containing the coin cell and crystal can be replaced, though one could simply plug in a new M48T58 module. Or, as [hacky] did, it’s also possible to cut open the ‘SNAPHAT’ top section and wire in a replacement battery module. With two 1.5V AA cells providing the 3V to the module, it was operational again.

Next up: working out what to write to the SRAM to make the coffee flow again.

Mobile Electronics Workstation Has It All In A Small Package

May 10, 2021 by Kristina Panos 13 Comments

Home is absolutely everything these days. Plenty of spaces around the abode have had to do double and triple duty as we navigate work, play, and everything in between. Although it’s been a great time to engage in hobbies and even find new ones, where exactly are we supposed put all the stuff that accumulates?

[Fabse89] needed a portable, usable solution for doing electronics work that could be easily packed away. They happened upon a tool case being thrown out, and repurposed it into a great one-stop solution for whenever the urge to play with pixies strikes.

[Fabse89] started by stripping the box out to the bare walls and modeling the inside in Fusion360. Then they built and cut an acrylic insert that holds two power supplies and a soldering station. There are fixed 5 V and 12 V outputs on one power supply, plus a variable supply that maxes out at 48 V.

When it came to tool storage options, [Fabse89] got lucky with a small, seldom-used set of plastic drawers that fits perfectly next to the power station. These hold all the small tools like flush cutters, pliers, and a de-soldering pump. The top section of the case folds back and is the perfect place for component storage boxes. We think this is a tidy solution and especially like that you don’t have to dismantle it to use it — can be used with everything in place and packed up quickly. We also like that the front lid pulls down into a makeshift table, so this really could go anywhere with mains power.

Acrylic not rugged enough for your tastes? Here’s a DIY supply that doubles as a melee weapon.