3D Printed Key-Code Is Plastic Digital Logic

April 6, 2017 by James Hobson 31 Comments

3D printers are great for creating static objects, but if you’re clever, it’s possible to print functional devices. If you’re absolutely brilliant you can go far beyond that, which is the case here. This door handle with a key-code lock does it all with 3D printing using mechanism designs that look like alien technology. This is just one application of a much more interesting mechanical digital logic they’re developing (PDF).

Working from the [Hasso-Plattner-Institut], the research team is focusing on metamaterials as mechanisms in and of themselves. The crux of this lock is a series of bistable springs that — if the correct code is entered — will trigger in series to unlock the door. The project builds on the grid of shearing cells seen in the door handle we featured last year. It happens quickly in the video, but the intricate cascade of the handle unlocking is a treat to witness.

It’s a fascinating show of mechanical design. The common elements of digital electronics are all present: set or unset bits, logic gates, propagation issues, the whole works. But there are added challenges in this system, like the need for special cells that can turn the logic chain by 90 degrees and split the signal into more than one part.

This signal splitting is seen in the upper right (bifurcation) and leads into what is in effect an amplifier. The locking bolt must be moved twice the distance of a normal cell, so a dual-cell input is necessary to offset the loss of force from the incoming smaller cells. Cognitively we understand this, but we’re still trying to gain an intuitive sense of the amplifer mechanism.

One thing’s for sure, the overall concept is far cooler than this admittedly awesome door lock mechanism. The paper is worth your time for a deep dive. It mentions their design editor software. You can play with it online but we don’t think it’s been updated to include the new logic cells yet.

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IOT Startup Bricks Customers Garage Door Intentionally

April 5, 2017 by Jack Laidlaw 202 Comments

Internet of Things startup Garadget remotely bricked an unhappy customer’s WiFi garage door for giving a bad Amazon review and being rude to company reps. Garadget device owner [Robert Martin] found out the hard way how quickly the device can turn a door into a wall. After leaving a negative Amazon review, and starting a thread on Garadget’s support forum complaining the device didn’t work with his iPhone, Martin was banned from the forum until December 27, 2019 for his choice of words and was told his comments and bad Amazon review had convinced Garadget staff to ban his device from their servers.

The response was not what you would expect a community-funded startup. “Technically there is no bricking, though,” the rep replied. “No changes are made to the hardware or the firmware of the device, just denied use of company servers.” Tell that to [Robert] who can’t get into his garage.

This caused some discontent amoung other customers wondering if it was just a matter of time before more paying customers are subjected to this outlandish treatment. The Register asked Garadget’s founder [Denis Grisak] about the situation, his response is quoted below.

It was a Bad PR Move, Martin has now had his server connection restored, and the IOT upstart has posted a public statement on the matter.– Garadget

This whole debacle brings us to the conclusion that the IoT boom has a lot of issues ahead that need to be straightened out especially when it comes to ethics and security. It’s bad enough to have to deal with the vagaries of IoT Security and companies who shut down their products because they’re just not making enough money. Now we have to worry about using “cloud” services because the people who own the little fluffy computers could just be jerks.

World Create Day: The Hackaday Event In Your Town

April 5, 2017 by Mike Szczys 4 Comments

It’s official, World Create Day is on April 22nd. Get together with hackers in your area and create something! This is best way to meet all the Hackaday readers in your area, and a great excuse to carve out a few hours of your busy life to have fun working on a project.

These are really easy to organize, but we can’t do it without you. Sign up now to host a meetup in your town!

The Hackaday community around the world will meetup and spend time building together on Saturday, April 22nd. If you’re like us you have a long list of projects you want to do ‘some day’, this is the day. Pack up your current build (or grab gear to start a new one), get together with some old and new friends, and hack on your projects with each other.

It’s traditional to block out a bit of time at the end for lightning talks to show off the builds each of you has been working on. Don’t forget to take pictures and post the story of your World Create Day meetup. We enjoyed getting a great look at many of last year’s meetups this way and want to expand the builds we feature on the front page this year.

Meetup Organizers Wanted

Fill out this form to let us know you want to host a meetup.

This is the second year of World Create Day. Last year we saw meetups in 64 cities. Many of those will happen again this year, but we also need you to organize an event in your area. We’ll help you get things set up and put your event up on the big map so others in your area will plan to join in. Do it now, if we get your shipping info early we’ll send you stickers and other swag to hand out at your gathering.

Build Something that Matters

The core of World Create Day is to stop making excuses and just build something. Since you’re already getting together with other people consider forming a team to enter the 2017 Hackaday Prize. Currently we’re in the idea phase: Design Your Concept means tackling a problem and planning a build to solve it. When you get a bunch of creative people together in one place, great ideas begin to flow. Seize the moment by turning that creativity into an entry for the Hackaday Prize and see where it takes you!

Learn Neural Network And Evolution Theory Fast

April 5, 2017 by Jack Laidlaw 32 Comments

[carykh] has a really interesting video series which can give a beginner or a pro a great insight into how neural networks operate and at the same time how evolution works. You may remember his work creating a Bach audio producing neural network, and this series again shows his talent at explaining the complex topic so anyone may understand.

He starts with 1000 “creatures”. Each has an internal clock which acts a bit like a heart beat however does not change speed throughout the creature’s life. Creatures also have nodes which cause friction with the ground but don’t collide with each other. Connecting the nodes are muscles which can stretch or contract and have different strengths.

At the beginning of the simulation the creatures are randomly generated along with their random traits. Some have longer/shorter muscles, while node and muscle positions are also randomly selected. Once this is set up they have one job: move from left to right as far as possible in 15 seconds.

Each creature has a chance to perform and 500 are then selected to evolve based on how far they managed to travel to the right of the starting position. The better the creature performs the higher the probability it will survive, although some of the high performing creatures randomly die and some lower performers randomly survive. The 500 surviving creatures reproduce asexually creating another 500 to replace the population that were killed off.

The simulation is run again and again until one or two types of species start to dominate. When this happens evolution slows down as the gene pool begins to get very similar. Occasionally a breakthrough will occur either creating a new species or improving the current best species leading to a bit of a competition for the top spot.

We think the series of four short YouTube videos (all around 5 mins each) that kick off the series demonstrate neural networks in a very visual way and make it really easy to understand. Whether you don’t know much about neural networks or you do and want to see something really cool, these are worthy of your time.

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How To Trick Your Electrical Meter By Saving Power

April 4, 2017 by Michael Uttmark 95 Comments

A group of Dutch scientists have been testing out some of today’s “smart” electrical meters to check their accuracy, among other things. Not ones to disappoint, the scientists have found consistently false readings that in some cases are 582% higher than actual energy consumption.

With experiments lasting for six months, the researchers tried to focus on meters representative of those commonly used in the Netherlands and manufactured between 2004 and 2014. Moreover, the researchers tried to reproduce standard household energy consumption patters rather than focusing on stress tests.

Their results? Well, “results varied wildly, with some meters reporting errors way above their disclosed range, going from -32% to +582%. Tests with uncommon results were repeated several times and the results were within a few percents of the original.” Moreover, “The greatest inaccuracies were seen when researchers combined dimmers with energy saving light bulbs and LED bulbs.” Not constrained to energy saving light bulbs, the inaccuracies are, ironically, tied to devices with integrated energy saving features. (Certainly makes us want to keep a close eye on our electric meters.)

“The reason for faulty readings appears to be the current sensor, and the associated circuitry,” said researchers. “The experimental results […] show that static energy meters can be pushed into faulty reading (positive and negative) if sufficiently fast pulsed currents are drawn by the consumer”

It is worth noting that there is contradictory research published by “the European voice of the providers of smart energy solutions” that maintains that “there is no reason to question smart metering technology”. Still, we wouldn’t blame you if you wanted a second opinion.

Thanks [acs] for sending this in!

The Shocking Truth About Transformerless Power Supplies

April 4, 2017 by Elliot Williams 114 Comments

Transformerless power supplies are showing up a lot here on Hackaday, especially in inexpensive products where the cost of a transformer would add significantly to the BOM. But transformerless power supplies are a double-edged sword. That title? Not clickbait. Poking around in a transformerless-powered device can turn your oscilloscope into a smoking pile or get you electrocuted if you don’t understand them and take proper safety precautions.

But this isn’t a scare piece. Transformerless designs are great in their proper place, and you’re probably going to encounter one someday because they’re in everything from LED lightbulbs to IoT WiFi switches. We’re going to look at how they work, and how to design and work on them safely, because you never know when you might want to hack on one.

Here’s the punchline: transformerless power supplies are safely useable only in situations where the entire device can be enclosed and nobody can accidentally come in contact with any part of it. That means no physical electrical connections in or out — RF and IR are fair game. And when you work with one, you have to know that any part of the circuit can be at mains voltage. Now read on to see why!

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How Many Parts In A Triumph Herald Heater?

April 4, 2017 by Jenny List 67 Comments

This Herald is in much better condition than my 12/50 was. Philafrenzy [CC BY-SA 4.0]

What was your first car? Mine was a 1965 Triumph Herald 12/50 in conifer green, and to be frank, it was a bit of a dog.

The Triumph Herald is a small saloon car manufactured between about 1959 and 1971. If you are British your grandparents probably had one, though if you are not a Brit you may have never heard of it. Americans may be familiar with the Triumph Spitfire sports car, a derivative on a shortened version of the same platform. It was an odd car even by the standards of British cars of the 1950s and 1960s. Standard Triumph, the manufacturer, had a problem with their pressing plant being owned by a rival, so had to design a car that used pressings of a smaller size that they could do in-house. Thus the Herald was one of the last British mass-produced cars to have a separate chassis, at a time when all other manufacturers had produced moncoques for years.

My 12/50 was the sporty model, it had the high-lift cam from the Spitfire and a full-length Britax sunroof. It was this sunroof that was its downfall, when I had it around a quarter century of rainwater had leaked in and rotted its rear bodywork. This combined with the engine being spectacularly tired and the Solex carburetor having a penchant for flooding the engine with petrol made it more of a pretty thing to look at than a useful piece of transport. But I loved it, tended it, and when it finally died irreparably I broke it for parts. Since then I’ve had four other Heralds of various different varieties, and the current one, a 1960 Herald 948, I’ve owned since the early 1990s. A piece of advice: never buy version 0 of a car.

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