Retrotechtacular: Core Competencies

As the dashing officer shown above will tell you, early data processing machines and ADP systems employed two types of magnetic cores for memory and other purposes. This 1961 U.S. Army training film is an introduction to the properties of ferrite cores, which are commonly made from nickel alloy and other magnetic materials. As this is only part one of a series, the metallic ribbon type of magnetic core is covered in some other segment we have yet to locate.

The use of magnetic cores for random access memory was built upon transformer theory and provided a rugged and low-power solution until the semiconductor came into vogue. Before that time, the humble ferrite core served many uses and did so very well. The Apollo Guidance Computer had erasable magnetic core memory, and much of its software was stored in core rope memory.

binary 1The film covers a lot of theory and does so clearly and concisely. It begins by explaining what a magnetic core is and why it’s used, and then moves on to describe how the cores are used to store bits and the method by which they can transfer information to other cores. Along the way, it provides background on bi-stable devices and provides explanation of magnetization behavior in terms of magnetizing force and flux density.

Continue reading “Retrotechtacular: Core Competencies”

Mooltipass Installation Process Is Now Dead Simple

In a few weeks the Hackaday community offline password keeper will reach a crowdfunding platform. This is a necessary step as only a high production volume will allow our $80 early bird perk target. We’ll therefore need you to spread the word.

Thanks to the Chromium development team, a few days ago the Mooltipass installation process became as simple as installing our app & extension. As you may remember, our device is enumerated as composite HID proprietary / HID standard keyboard. This makes it completely driverless for all operating systems and enables standalone operation as the Mooltipass can type logins and passwords selected through its user interface. Management communications are therefore done through the Mooltipass HID proprietary interface, which Chrome 38 now natively supports through its chrome.hid API. The simpler our installation process is, the more likely the final users will appreciate the fruit of our hard labor.

As our last post mentioned there’s still plenty of space for future contributors to implement new functionalities. Our future crowdfunding campaign will allow us to find javascript developers for the remaining app & extensions tasks and also implement other browsers support. Want to stay tuned of the Mooltipass launch date? Subscribe to our official Google Group!

 

Ask Hackaday: Who Is Going To Build This Pneumatic Transmission Thing?

fluid_transmission

Disney research is doing what they do best, building really cool stuff for Disney and telling the rest of the world how cool they are. This time, it’s a very low friction fluid transmission device designed for animatronics.

From testing a few toy robotic arms, we can say without a doubt that servos and motors are not the way to go if you’re designing robots and animatronics that need lifelike motion. To fix this, a few researchers at Disney Pittsburgh have turned to pneumatics and hydraulics, where one joint is controlled by two sets of pistons. It’s extremely similar to the pneumatic LEGO, but more precise and much more lifelike.

The system uses a pair of cylinders on each joint of a robot. Disney is using a rolling diaphragm to seal the working fluid in its tubes and cylinders. This is an extremely low-friction device without any shakiness or jitters found with simple o-ring pneumatics and hydraulics.

The system is backdriveable, meaning one robotic arm can control another, and the other way around. Since we’re dealing with hydraulics, the cylinders (and robotic/animatronic devices) don’t need to be the same size; a small device could easily control a larger copy of itself, and vice versa.

The devices are fairly simple, with gears, toothed belts, and bits of plastic between them. The only unique part of these robots is the rolling diaphragm, and we have no idea where to source this. It looks like it would be great for some robotics or an Iron Man-esque mech suit, but being able to source the components will be a challenge.

You can check out the videos of these devices below, and if you have any idea on how to build your own, leave a note in the comments.

Continue reading “Ask Hackaday: Who Is Going To Build This Pneumatic Transmission Thing?”

Thumbnail that say The Hacklet

Hacklet 18 – Tick Tock, It’s Time For Clocks

18

In three words, Hackers love clocks. Not only do we think that digital watches are still a pretty neat idea, we love all manner of timepieces. This episode of The Hacklet focuses on the clock projects we’ve found over on Hackaday.io.

xkcdHardwareWe start with [rawe] and [tabascoeye], who both put the famous XKCD “now” clock into hardware. [tabascoeye] used a stepper motor in his xkcd world clock. [rawe] didn’t have any steppers handy, so he grabbed a cheap wall clock from Ikea for his xkcd.com/now clock in hardware. The now clock needs a 24 hour movement. Ikea only sells 12 hour movements, so [rawe] hacked in a 555 and some logic to divide the clock’s crystal by two. He’s currently using an EEVblog uCurrent to verify his modified clockwork consumes about half a milliwatt.

touchscreenclockNext up is [Craig Bonsignore] and his Touchscreen Alarm Clock. [Craig] got sick of store-bought alarm clocks, so he built his own. Then he modified it, added a few features, and kept building! The current incarnation of the clock has a pretty novel interface: a touchscreen over a bicolor LED matrix. The rest of the clock consists of an Arduino, an Adafruit Wave shield, and a Macetech Chronodot. [Craig] is currently mashing up these open source designs and building a single Arduino shield for his clock.

irisledclock[Warren Janssens] took the minimalist route with The Iris Clock. Iris is a ring of WS2812 RGB LEDs. The LEDs are mounted behind a wall colored piece of wood in such a way that you can only see their glow on the clock frame and the wall beyond it. This helps a with the eye searing effect WS2812s can have when viewed directly – even when dimmed with PWM. The code is mainly C with some AVR assembly thrown in to control the LEDs. [Warren] has given Iris 8 different time modes, from hour/minute/second to percentage of day with sunrise and sunset markers. With so many modes, the only hard part is knowing how to read the time Iris is displaying!

stargate[David Hopkins] also built a ring clock. His Stargate LED Clock not only tells time, but is a great replica of the Stargate from the TV series. [David] used four Adafruit WS2812 Neopixel segments to build a full 60 RGB LED ring. The Stargate runs on an Arduino nano with a real-time clock chip to keep accurate time. A photoresistor allows the Stargate to automatically dim at night. With some slick programming [David] added everything from a visual hourly “chime” to a smooth fade from LED to LED.

bendulum[dehne1] gives us something completely different with The Bendulum Clock. A bendulum is [dehne1’s] own creation consisting of an inverted pendulum built without a pivot. The inverted pendulum swings by bending along its length. In [dehne1’s] design, the bendulum is made out of a spring steel strip rescued from a car windshield wiper. The Bendulum doesn’t have a mechanical escapement, but an electromagnet sensed and driven by an Arduino. The amazing part of this project is that  [dehne1] isn’t using a real-time clock chip. The standard 8MHz Arduino resonator is calibrated over various temperatures, then used to calibrate the bendulum itself. The result is a clock that can be accurate within 1 minute each day. [dehne1] mounted his clock inside a custom wood case. We think it looks great, and want one for Hackaday HQ!

We’ve used enough clock ticks for this episode of The Hacklet. As always, see you next week. Same hack time, same hack channel, bringing you the best of Hackaday.io!

Still want more? Check out our Timepiece List!

Fail Of The Week: Transparent Circuit Design Is Clearly A Challenge

[Frank Zhao] wanted to try his hand at making a transparent circuit board. His plan was to etch the paths with a laser cutter and fill in the troughs with conductive ink. The grooves are ~0.1mm deep x ~0.8mm wide.

He used nickel ink, which is slightly cheaper than silver ink. The ink was among the least of his problems, though. At a measured resistance of several hundred ohms per inch, it was already a deal breaker since his circuit can’t function with a voltage drop above 0.3V. To make matters worse, the valleys are rough due to the motion of the laser cutter and don’t play well with the push-to-dispense nature of the pen’s tip. This caused some overflow that he couldn’t deal with elegantly since the ink also happens to melt acrylic.

[Frank] is going to have another go at it with copper foil and wider tracks. Do you think he would have fared better with silver ink and a different delivery method, like a transfer pipette? How about deeper grooves?


2013-09-05-Hackaday-Fail-tips-tileFail of the Week is a Hackaday column which runs every Thursday. Help keep the fun rolling by writing about your past failures and sending us a link to the story — or sending in links to fail write ups you find in your Internet travels.

Retrotechtacular: The Future’s So Bright, We’re Gonna Need Photochromic Windowpanes

This is a day in the life of the Shaw family in the summer of 1999 as the Philco-Ford Corporation imagined it from the space-age optimism of 1967. It begins with Karen Shaw and her son, James. They’re at the beach, building a sand castle model of their modular, hexagonal house and discussing life. Ominous music plays as they return in flowing caftans to their car, a Ford Seatte-ite XXI with its doors carelessly left open. You might recognize Karen as Marj Dusay, who would later beam aboard the USS Enterprise and remove Spock’s brain.

The father, Mike Shaw, is an astrophysicist working to colonize Mars and to breed giant, hardy peaches in his spare time. He’s played by iconic American game show host Wink Martindale. Oddly enough, Wink’s first gig was hosting a Memphis-based children’s show called Mars Patrol. He went on to fame with classics such as Tic Tac Dough, Card Sharks, Password Plus, and Trivial Pursuit.

Mike calls up some pictures of the parent trees he’s using on a screen that’s connected to the family computer. While many of today’s families have such a device, this beast is almost sentient. We learn throughout the film that it micromanages the family within an inch of their lives by keeping tabs on their physiology, activities, financial matters, and in James’ case, education.

Continue reading “Retrotechtacular: The Future’s So Bright, We’re Gonna Need Photochromic Windowpanes”

Hackaday Links Column Banner

Hackaday Links: October 5th, 2014

Good news from CadSoft this week. They didn’t miss all the complaints about their decision to use a Node Lock License for EAGLE 7. This had meant that users of the popular PCB design software would be limit on how many machines they could use the software with a license. They have removed License Management from the package (and all the citizens rejoiced).

We’re tripping over the growing pile of hardware that boast the “next-big-thing” in getting devices onto a network. That’s not a complaint at all. This time around it’s a cell chip, the U-blox SARA-U260, which can connect to 3G on the AT&T network and is just 16x26mm. They call it world’s smallest but we have no idea if that’s true or not. Anyone have a source and/or pricing for these? [Thanks Austin]

This guy loves his Nixie tube. How much? To the extent that he built up a hardware and software interface that behaves much like a pet. It’s voice activated, and the infectious delight of [Glasslinger’s] video demo is in itself worth watching. [Thanks Morris]

Making this Magnetic Stripe Reader work as a USB device is really nothing more than adding a serial-to-USB converter. The journey to find the way to add the converter makes for a fun read though.

We know from watching Breaking Bad that you can kill power to a building by shorting the power lines outside with a huge bouquet of mylar balloons. This installation is a twist on the idea. Connecting one mylar balloon to a Van de Graaff generator and floating it next to another results in an oscillating repel-discharge-repel cycle. [Thanks filnt via NPR]