Bike-Driven Scarf Knitter Is An Accessory To Warmth

June 11, 2018 by 25 Comments

Despite all our technological achievements, humans still spend a lot of time waiting around for trains. Add a stiff winter breeze to the injury of commuting, and you’ve got a classic recipe for misery. [George Barratt-Jones] decided to inject some warmth into this scene by inviting people to knit a free scarf for themselves by riding a bike.

All a person has to do is ride the Cyclo-Knitter for five minutes and marvel at their handiwork. By the time the scarf is finished, they’ve cycled past being cold, and they have something to hold in the warmth. Cyclo-Knitter is essentially an Addi Express knitting machine being belt-driven by a stationary bike. Power is transferred from the bike through large, handmade wooden gears using old bike tire inner tubes as belts. [George] built a wooden tower to hold the machine and give the growing scarf a protected space to dangle.

We love the utility of this project as much as the joy it inspires in everyone who tries it. Check out their scarves and their reactions after the break. We haven’t seen people this happy to see something they weren’t expecting since that billboard that kills Zika mosquitoes.

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Hacking When It Counts: The Magnetron Goes To War

June 11, 2018 by 36 Comments

In 1940, England was in a dangerous predicament. The Nazi war machine had been sweeping across Europe for almost two years, claiming countries in a crescent from Norway to France and cutting off the island from the Continent. The Battle of Britain was raging in the skies above the English Channel and southern coast of the country, while the Blitz ravaged London with a nightly rain of bombs and terror. The entire country was mobilized, prepared for Hitler’s inevitable invasion force to sweep across the Channel and claim another victim.

We’ve seen before that no idea that could possibly help turn the tide was considered too risky or too wild to take a chance on. Indeed, many of the ideas that sprang from the fertile and desperate minds of British inventors went on to influence the course of the war in ways they could never have been predicted. But there was one invention that not only influenced the war but has a solid claim on being its key invention, one without which the outcome of the war almost certainly would have been far worse, and one that would become a critical technology of the post-war era that would lead directly to innovations in communications, material science, and beyond. And the risks taken to develop this idea, the cavity magnetron, and field usable systems based on it are breathtaking in their scope and audacity. Here’s how the magnetron went to war.

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James Bruton's openDog inverse kinematics

[James Bruton] Is Making A Dog: OpenDog Project

June 11, 2018 by 32 Comments

There was a time when a two-legged walking robot was the thing to make. But after seeing years of Boston Dynamic’s amazing four-legged one’s, more DIYers are switching to quadrupeds. Now we can add master DIY robot builder [James Bruton] to the list with his openDog project. What’s exciting here is that with [James’] extensive robot-building background, this is more like starting the challenge from the middle rather than the beginning and we should see exciting results sooner rather than later.

James' motor and ball screws
James’ motor and ball screws

Thus far [James] has gone through the planning stage, having iterated through a few versions using Fusion 360, and he’s now purchased the parts. It’s going to be about the same size as Boston Robotic’s SpotMini and uses three motors for each leg. He considered going with planetary gearboxes on the motors but experienced a certain amount of play, or backlash, with them in his BB-9E project so this time he’s going with ball screws as he did with his exoskeleton. (Did we mention his extensive background?)

Each leg is actually made up of an upper and lower leg, which means his processing is going to have to include some inverse kinematics. That’s where the code decides where it wants the foot to go and then has to compute backwards from there how to angle the legs to achieve that. Again drawing from experience when he’s done it the hard way in the past, this time he’s designed the leg geometry to make those calculations easy. Having written up some code to do the calculations, he’s compared the computed angles with the measurements he gets from positioning the legs in Fusion 360 and found that his code is right on. We’re excited by what we’ve seen so far and bet it’ll be standing and walking in no time. Check out his progress in the video below.

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FPGA Persistently Rick Rolls You

June 11, 2018 by 13 Comments

When [Im-pro] wants a display, he wants it to spin.  So he built a persistence of vision (POV) display capable of showing a 12-bit color image of 131 x 131 pixels at 16 frames per second. You can see a video about the project below, but don’t worry, you can view it on your normal monitor.

The project starts with a Java-based screen capture on a PC. Data goes to the display wirelessly to an ESP8266. However, the actual display drive is done by an FPGA that drives the motor, reads a hall effect index sensor, and lights the LEDs.

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Custom Buttons For Your Game Controller

June 10, 2018 by 9 Comments

Console gamers have relatively few options when it comes to hardware hacking, unless they wish to partake of some extreme modifications that threaten the very integrity of their machines. So without reaching for a Dremel, how can you insert a little individuality into the same standard components all your friends have?

It seems one answer is to customise your controller with some different buttons. There are commercial outfits that will supply your needs in this direction, but they aren’t always cheap, and plenty of older machines have no products available. This isn’t  a problem for [RockerGaming] though, who shows us how to cast your own set of custom buttons using a silicone mold taken from the originals.

The video is a step-by-step walkthrough of the molding process that could just as easily be applied to any other small plastic parts and is not unique to console buttons. The subjects come from a Sega Saturn controller, in the video a beige model, which raises a passing interest among European Hackaday scribes who remember the Saturn as a black console.

We see the preparation of the original buttons and mold. An acrylic golf ball trophy display case is pressed into service. (Who knew those were even a thing!) A dye is added to the two-part silicone to provide a visual mixing aid, and once the cast mold is separated from the buttons the final resin is poured into it. The cloned buttons are tidied up underneath with a Dremel, and the controller is reassembled.

A set of custom buttons will not improve your gaming, but underlying this is the fact that resin casting is a useful skill. It’s somewhere we’ve been before in depth, so it’s worth reading our guide from back in 2016.

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High Voltage Switching With MOSFETs

June 10, 2018 by 9 Comments

Using a MOSFET as a switch is generally pretty simple. Make the gate voltage sufficient with respect to the source and current flows through the channel. However, if you are switching higher voltages, you may need some additional circuitry to protect the device’s gate and possibly the microcontroller driving the whole thing, too. [Lewis] discusses high voltage switching in the latest in his series of videos dealing with MOSFETs. You can see the video below.

You’ll see in the video a breadboard setup driving a 50 V load and also a higher-voltage H-bridge. There are three major topics covered: Using an optoisolator, using a gate bleeder resistor, and using a zener diode to limit gate voltage.

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Hackaday Links: Benchoff Rants On Flying Cars

June 10, 2018 by 52 Comments

It’s time for Computex, and that means [Linus] has dropped something. I don’t know what, but he’s dropped something. It’s a meme or something at this point. What were the highlights? Asus announced Project Precog, a laptop with two screens. Yes, a touchscreen keyboard. It’s the 2018 version of the IBM Transnote or whatever that Microsoft thing was called. Why is it called Project Precog? Because AI or whatever. Unimaginative marketing is terrible. Intel is going to launch a 28-core CPU, and AMD is introducing a 32-core CPU. Awesome, core wars. And here’s RGB RAM because stuffing a case full of cold cathode lighting is sooo early-2000s.

Need a reverse engineering challenge? Here’s something from American Science and Surplus. It’s a 48 x 12 LED matrix, loaded up with driver ICs and power regulators. $20 a piece, so stock up and save.

Finally, the main event. The biggest story in aviation this week is that a media embargo has lifted on the Kitty Hawk Flyer. Kitty Hawk is a startup funded by Larry Page, CEO’d by Sebastian Thrun, and has received $6.5 M in funding. The Flyer, a one-man decacopter, was announced to the world through CNN Money and Casey Neistat. It should be noted that in the entire media landscape, these are the two outlets most ignorant of aviation: CNN needs no explanation, and Neistat flies quadcopters through the Hudson River Corridor at 1000 feet AGL. Additionally, Kitty Hawk is not exhibiting at AirVenture next month, which leads me to believe Kitty Hawk is trying to stay out of the aviation industry or simply doesn’t want knowledgeable people asking them questions. But I digress.

The Kitty Hawk Flyer is being promoted by the company as “a personal flying vehicle… to make flying part of everyday life” and a machine that will give you, “a world free from traffic”. It is being billed by CNN and Neistat as ‘a flying car’. Kitty Hawk is just fine with allowing the media to call it as such. Additionally, Sebastian Thrun is making claims about the Flyer that are disingenuous at best, outright illegal at worst, and should draw the ire of any investors.

In the CNN Money piece, Thrun claims the Flyer is capable of traveling at 100 miles per hour, which would be illegal. The Flier is certified as a Part 103 Ultralight, and under that regulation the Flyer “is not capable of more than 55 knots calibrated airspeed at full power in level flight.” The Flyer may also be overweight. The first version of the Flyer was basically a decacopter with a seat, and weighed in at 220 pounds. Part 103 regulations have a limit of 254 pounds, and it’s entirely possible there are more than 34 pounds of chassis and fiberglass on the latest version. I should also mention the safety training, while not required for a Part 103 ultralight, is insufficient: Casey Neistat’s underwater egress training was done in a Chuck E. Cheese-style ball pit. You can breathe in a ball pit, you can’t breathe underwater.

But legality aside, a Part 103 ‘flying car’ is just about the dumbest idea ever. You can’t use it to commute, and you’re welcome to call your local FSDO to confirm that. You’re not going to fly it in New York City or San Francisco because there are airports in the way. At best, this is a ‘flying ATV’ that you would take out on your farm; a toy for rich people. At worst, it’s the latest example of the Silicon Valley philosophy of ‘ignore laws and break things’.