Quantum Mechanics In Your Processor: Tunneling And Transistors

July 31, 2015 by Will Sweatman 13 Comments

By the turn of the 19th century, most scientists were convinced that the natural world was composed of atoms. [Einstein’s] 1905 paper on Brownian motion, which links the behavior of tiny particles suspended in a liquid to the movement of atoms put the nail in the coffin of the anti-atom crowd. No one could actually see atoms, however. The typical size of a single atom ranges from 30 to 300 picometers. With the wavelength of visible light coming in at a whopping 400 – 700 nanometers, it is simply not possible to “see” an atom. Not possible with visible light, that is. It was the summer of 1982 when Gerd Binnig and Heinrich Rohrer, two researchers at IBM’s Zurich Research Laboratory, show to the world the first ever visual image of an atomic structure. They would be awarded the Nobel prize in physics for their invention in 1986.

The Scanning Tunneling Microscope

IBM’s Scanning Tunneling Microscope, or STM for short, uses an atomically sharp needle that passes over the surface of an (electrically conductive) object – the distance between the tip and object being just a few hundred picometers, or the diameter of a large atom.

A small voltage is applied between the needle and the object. Electrons ‘move’ from the object to the needle tip. The needle scans the object, much like a CRT screen is scanned. A current from the object to the needed is measured. The tip of the needle is moved up and down so that this current value does not change, thus allowing the needle to perfectly contour the object as it scans. If one makes a visual image of the current values after the scan is complete, individual atoms become recognizable. Some of this might sound familiar, as we’ve seen a handful of people make electron microscopes from scratch. What we’re going to focus on in this article is how these electrons ‘move’ from the object to the needle. Unless you’re well versed in quantum mechanics, the answer might just leave your jaw in the same position as this image will from a home built STM machine.

Continue reading “Quantum Mechanics In Your Processor: Tunneling And Transistors” →

Say It With Me: Input Impedance

July 29, 2015 by Elliot Williams 37 Comments

In the “Say It with Me” series, we’ll take a commonly used concept out of electronics and explain it the best we can. If there’s something that’s been bugging you, or a certain term or concept that keeps cropping up in your projects, let us know. We’ll write about it!

What’s up with input impedance? You hear people talking about it, but why does it matter? And impedance matching? Let’s break it all down.

First of all, impedance is the frequency-dependent sister of resistance, so for intuition we’ll first work through the cases of purely resistive impedance. And that’s almost fine if you’re only ever working at one frequency. We’ll hint at the full-blown impedance = resistance + reactance version at the end, but it’s really its own topic. For now, pretend that your circuits aren’t reactive.

Continue reading “Say It With Me: Input Impedance” →

Retrotechtacular: Fantastic Backyard Inventions Of Yore

July 28, 2015 by Kristina Panos 9 Comments

News corporation [British Pathé] created many newsreels and documentaries throughout their 60-year history. Recently, the company released scores of films from their archives and put them on the internet. Here is a delightful collection of short films they created that highlight strange and wonderful inventions in various fields, including transportation and communication.

One of the standout inventions is the Dynasphere, a mono-wheeled vehicle that probably deserves its own week in the Retrotechtacular spotlight. There are a couple of pedal-powered planes that may have inspired the Gossamer Condor, and a hover scooter that resembles an air hockey striker and doubles as a leaf blower. In another film, a man drives a Vespa to the banks of the Thames and parks it. He pulls a fin down from each side of the scooter, turning it into a seafaring craft. When he snaps his fingers, a cute girl appears from somewhere just outside the frame. She climbs on the back, and they take off across the water.

The average running time of these films is about two minutes. Some of them are much shorter, prompting many questions. Fortunately, most of the video descriptions have links with more information about these marvelous inventions. Almost all of the inventors in these films show a complete disregard for safety, but nearly everyone involved seems to be having the time of their lives.

Continue reading “Retrotechtacular: Fantastic Backyard Inventions Of Yore” →

Embed With Elliot: There Is No Arduino “Language”

July 28, 2015 by Elliot Williams 157 Comments

This installment of Embed with Elliot begins with a crazy rant. If you want to read the next couple of paragraphs out loud to yourself with something like an American-accented Dave-Jones-of-EEVBlog whine, it probably won’t hurt. Because, for all the good Arduino has done for the Hackaday audience, there’s two aspects that really get our goat.

(Rant-mode on!)

First off is the “sketch” thing. Listen up, Arduino people, you’re not writing “sketches”! It’s code. You’re not sketching, you’re coding, even if you’re an artist. If you continue to call C++ code a “sketch”, we get to refer to our next watercolor sloppings as “writing buggy COBOL”.

And you’re not writing “in Arduino”. You’re writing in C/C++, using a library of functions with a fairly consistent API. There is no “Arduino language” and your “.ino” files are three lines away from being standard C++. And this obfuscation hurts you as an Arduino user and artificially blocks your progress into a “real” programmer.

(End of rant.)

Let’s take that second rant a little bit seriously and dig into the Arduino libraries to see if it’s Arduinos all the way down, or if there’s terra firma just beneath. If you started out with Arduino and you’re looking for the next steps to take to push your programming chops forward, this is a gentle way to break out of the Arduino confines. Or maybe just to peek inside the black box.

Continue reading “Embed With Elliot: There Is No Arduino “Language”” →

Hackaday Prize Worldwide : New Delhi Kicad + Show And Tell

July 28, 2015 by Anool Mahidharia 5 Comments

While Mumbai and Bengaluru have an active and large hacker community, New Delhi, India’s capital, seems to have leapfrogged ahead when it comes to hackerspaces – four at last count. So when the latest one in town, Maker’s Asylum, opened it’s doors last month, we decided to put together a hacker congregation to bring the community together and introduce them to the Hackaday Prize. Having already done Hackaday Prize bring-a-hack events in Mumbai and Bengaluru, we thought of doing something more substantial – a day long KiCad EDA workshop followed in the evening by a Show-n-Tell brag show.

Hackaday’s [Matt Berggren a.k.a. @technolomaniac] has done a couple of “Design a PCB from zero to WiFi with Hackaday!” Eagle EDA workshops recently. He designed a simple breakout board that allowed connecting an ESP-01 module to the USB port via an USB-UART cable with level conversion, pull up resistors and push button switches to make it easy to program. We had a slightly delayed start, so I quickly rushed through the awesome presentation that [Matt] has prepared, running through the “What is a PCB?” section and skipping the rest. We also discussed a couple of candidate designs for the day’s workshop – a pair of ATtiny line following robots, a simple Attiny SmartLED controller, but eventually, everyone got excited when I mentioned “ESP-8266” !

“What is a PCB?”

KiCad workshop

A helping hand

Continue reading “Hackaday Prize Worldwide : New Delhi Kicad + Show And Tell” →

The Best Of Boston Hackers At Artisan’s Asylum

July 27, 2015 by Mike Szczys 3 Comments

We were in Boston last week and Artistan’s Asylum welcomed us in to host a Hackaday Meetup. We usually pack the place when the Hackaday community turns out, but this was exceptional. This hackerspace has a sizeable open area that I’m told fits triple-digits and we were using all of it. In addition to food and beverage (courtesy of our parent company Supplyframe who also make trips like this one a possibility), we had lighting talks for people to show off their projects. One of the hits was a functional hoverboard shown above, but there were dozens of others.

Here is the quick gallery of images (from our Hackaday.io event page) to give you an overview. After the break you’ll find dozens more highlighting the builds which were being shown off.

Working Hoverboard

We brought the Hackaday Omnibus with us

Gentleman in white makes clothes with hundred+ yo machines

Spaceships made of duct tape

[Jimmy Rogers] and [Sophi Kravitz] having a good time

Lightning talks

Continue reading “The Best Of Boston Hackers At Artisan’s Asylum” →

Hacklet 57 – CNC Hacks

July 24, 2015 by Adam Fabio 13 Comments

Everyone’s first microcontroller project is making an LED blink. It’s become the de-facto “Hello World” of hardware hacking. There’s something about seeing wires you connected and the code you wrote come together to make something happen in the real world. More than just pixels on a screen, the LED is tangible. It’s only a short jump from blinking LEDs to making things move. Making things move is like a those gateway drug – it leads to bigger things like robots, electric cars, and CNC machines. Computer Numerical Control (CNC) is the art of using a computer to control movement. The term is usually applied to machine tools, which cut, engrave, or perform other operations on wood, plastic, metal and other materials. In short, tools to make more things. It’s no surprise that hackers love CNCs. This week’s Hacklet is all about some of the best CNC projects on Hackaday.io!

We start with [Charliex] and Grizzly G0704 CNC Conversion. [Charliex] wanted a stout machine capable of milling metal. He started with a Grizzly G0704, which is small compared to a standard knee mill, but still plenty capable of milling steel. [Charliex] added a Flashcut CNC conversion kit to his mill. While they call them “conversion kits” there is still quite a bit of DIY ingenuity required to get a system like this going. [Charliex] found his spindle runout was way out of spec, even for a Chinese mill. New bearings and a belt conversion kit made things much smoother and quieter as well. The modded G0704 is now spending its days cutting parts in [Charliex’s] garage.

Next up is [brashtim] with Makesmith CNC. Makesmith was [brashtim’s] entry in the 2014 Hackaday prize. While it didn’t win the prize, Makesmith did go on to have a very successful Kickstarter, with all the machines shipping in December of 2014. The machine itself is unorthodox. It uses closed loop control like large CNC machines, rather than open loop stepper motors often found in desktop units. The drive motors are hobby type servos. We’re not talking standard servos either – [brashtim] picked microservos. By using servos, common hardware store parts, and laser cut acrylic, [brashtim] kept costs down. The machine performs quite well though, easily milling through wood, plastic, foam, and printed circuit boards.

Next we have [Kenji Larsen] with Reactron material processor: Wireless CNC mill. [Kenji] started with a Shapeoko 2, and gave it the Reactron treatment. The stock controller was replaced with a Protoneer shield, which is connected to the Reactron network via a HopeRF radio module. The knockoff rotary tool included with the kit was replaced with a DeWalt DW660 for heavy-duty jobs, or a quieter Black and Decker RTX-6. A tool mounted endoscope keeps an eye on the work. [Kenji] mounted the entire mill in a custom enclosure of foam and Roxul insulation. The enclosure deadens the sound, but it also keeps heat in. [Kenji] plans to add a heat exchanger to keep things cool while maintaining relative quiet in his shop.

Finally we have a [hebel23] with DIY Multiplex Plywood CNC Router. [hebel23] wanted to build a big machine within a budget – specifically a working area of 400 x 600 x 100 mm and a budget of 800 Euro. As the name implies, [hebel23] used birch plywood as the frame of his machine. He chose high quality plywood rather than the cheap stuff found in the big box stores. This gives the machine a stable frame. The moving components of the machine are also nice – ball screws, linear bearings, and good stepper controllers. The stepper motors themselves are NEMA-23 units, which should give the CNC plenty of power to cut through wood, plastic, and even light cuts on metal. [hebel23] spent a lot of time on the little details of his CNC, like adding an emergency stop switch, and a wire-chain to keep his gantry control wires from ending up tangled up in the work piece. The end result is a CNC which would look great in anyone’s workshop.

If you want more CNC goodness, check out our brand new CNC project list! Did I miss your project? Don’t be shy, just drop me a message on Hackaday.io. That’s it for this week’s Hacklet, As always, see you next week. Same hack time, same hack channel, bringing you the best of Hackaday.io!