Lise Meitner: A Physicist Who Never Lost Her Humanity

December 21, 2015 by Dan Maloney 46 Comments

It is said that the first casualty of war is the truth, and few wars have demonstrated that more than World War II. One scientist, whose insights would make the atomic age possible, would learn a harsh lesson at the outset of the war about how scientific truth can easily be trumped by politics and bigotry.

Lise Meitner was born into a prosperous Jewish family in Vienna in 1878. Her father, a lawyer and chess master, took the unusual step of encouraging his daughter’s education. In a time when women were not allowed to attend institutions of higher learning, Lise was able to pursue her interest in physics with a private education funded by her father. His continued support, both emotional and financial, would prove important throughout Lise’s early career. Continue reading “Lise Meitner: A Physicist Who Never Lost Her Humanity” →

Scratching Vinyl Straddles Physical And Digital Realms

December 21, 2015 by Elliot Williams 10 Comments

The life of a modern DJ is hard. [Gergely] loves his apps, but the MIDI controller that works with the app feels wrong when he’s scratching, and the best physical interfaces for scratching only work with their dedicated machines. [Gergely]’s blog documents his adventures in building an interface to drive his iPad apps from a physical turntable. But be warned, there’s a lot here and your best bet is to start at the beginning of the blog (scroll down) and work your way up. Or just let us guide you through it.

In one of his earliest posts he lays out his ideal solution: a black box that interprets time-code vinyl records and emulates the MIDI output of the sub-par MIDI controller. Sounds easy, right? [Gergely] gets the MIDI side working fairly early on, because it’s comparatively simple to sniff USB traffic and emulate it. So now he’s got control over the MIDI-driven app, and the hard part of interfacing with the real world began.

After experimenting a lot with timecode vinyl, [Gergely] gives up on that and looks for an easier alternative. He also considers using an optical mouse, but that turns out to be a dead-end as well. Finally, [Gergely] settled on using a Tascam TT-M1, which is basically an optical encoder that sits on top of the record, and that makes the microcontroller’s job a lot easier. You can see the result in the video below the break.

And then in a surprise ending worthy of M. Night (“I see dead people”) Shyamalan he pulls timecode vinyl out of the grave, builds up a small hardware translator, and gets his original plan working. But we have the feeling that he’s not done yet: he also made a 3D printed optical-mouse holder.

Continue reading “Scratching Vinyl Straddles Physical And Digital Realms” →

Here’s The Reason The FAA’s Drone Registration System Doesn’t Make Sense

December 21, 2015 by Brian Benchoff 434 Comments

Last week, the US Department of Transportation and FAA released their rules governing drones, model aircraft, unmanned aerial systems, and quadcopters – a rose by any other name will be regulated as such. Now that the online registration system is up and running.

The requirements for registering yourself under the FAA’s UAS registration system are simple: if you fly a model aircraft, drone, control line model, or unmanned aerial system weighing more than 250g (0.55 lb), you are compelled under threat of civil and criminal penalties to register.

This is, by far, one of the simplest rules ever promulgated by the FAA, and looking at the full text shows how complicated this rule could have been. Representatives from the Academy of Model Aircraft, the Air Line Pilots Association, the Consumer Electronics Association weighed in on what types of aircraft should be registered, how they should be registered, and even how registration should be displayed.

Considerable attention was given to the weight limit; bird strikes are an issue in aviation, and unlike drones, bird strikes have actually brought down airliners. The FAA’s own wildlife strike report says, “species with body masses < 1 kilogram (2.2 lbs) are excluded from database,”. The Academy of Model Aircraft pushed to have the minimum weight requiring registration at two pounds, citing their Park Flyer program to define what a ‘toy’ is.

Rules considering the payload carrying ability of an unmanned aerial system were considered, the inherent difference between fixed wing and rotors or quadcopters was considered, and even the ability to drop toy bombs was used in the decision-making process that would eventually put all remotely piloted craft weighing over 250g under the FAA’s jurisdiction. We must at least give the FAA credit for doing what they said they would do: regulate drones in a way that anyone standing in line at a toy store could understand. While the FAA may have crafted one of the simplest rules in the history of the administration, this rule might not actually be legal.

Continue reading “Here’s The Reason The FAA’s Drone Registration System Doesn’t Make Sense” →

Giving The C64 A WiFi Modem

December 21, 2015 by Brian Benchoff 21 Comments

If there’s any indication of the Commodore 64’s longevity, it’s the number of peripherals and add-ons that are still being designed and built. Right now, you can add an SD card to a C64, a technology that was introduced sixteen years after the release of the Commodore 64. Thanks to [Leif Bloomquist], you can also add WiFi to the most cherished of the home computers.

[Leif]’s WiFi modem for the C64 is made of two major components. The first is a Microview OLED display that allows the user to add SSIDs, passwords, and configure the network over USB. The second large module is the a Roving Networks ‘WiFly’ adapter. It’s a WiFi adapter that uses the familiar Xbee pinout, making this not just a WiFi adapter for the C64, but an adapter for just about every wireless networking protocol out there.

[Leif] introduced this WiFi modem for the C64 at the World of Commodore earlier this month in Toronto. There, it garnered a lot of attention from the Commodore aficionados and one was able to do a video review of the hardware. You can check out [Alterus] loading up a BBS over Wifi in the video below.

Continue reading “Giving The C64 A WiFi Modem” →

Reverse Engineering The ARM ALU

December 21, 2015 by Al Williams 21 Comments

[Dave] wanted to learn more about the ARM architecture, so he started with an image of the ARMV1 die. If you’ve had some experience looking at CPU die, you can make some pretty good guesses at what parts of the chip have certain functions. [Dave], however, went further. He reverse engineered the entire ALU–about 2,200 transistors worth.

Continue reading “Reverse Engineering The ARM ALU” →

RGB LED Ceiling Display

December 20, 2015 by Anool Mahidharia 8 Comments

Disco Floor’s are passé. [dennis1a4] turned them upside down and built an awesome RGB LED ceiling display using some simple hardware and a lot of elbow grease. His main room ceiling was exactly 32 ft x 20 ft and using 2 sq. ft tiles, he figured he could make a nice grid using 160 WS2812B RGB LEDs. A Teensy mounted in the ceiling does all the heavy lifting, with two serial Bluetooth modules connected to it. These get connected to two Bluetooth enabled NES game controllers. Each of the NES controller is stuffed with an Arduino Pro Mini, a Bluetooth module, Li-Ion battery and a USB charge controller.

Bluetooth is in non-secure mode, allowing him to connect to the Teensy, and control the LEDs, from other devices besides the NES controllers. The Teensy is mounted at the centre of the ceiling to ensure a good Bluetooth link. Programming required a lot of thought and time but he did manage to include animations as well as popular games such as Snake and Tetris.

The hard part was wiring up all of the 160 LED pixels. Instead of mounting the 5050 SMD LED’s on PCBs, [dennis1a4] wired them all up “dead bug” style. Each pixel has one LED, a 100nF decoupling capacitor, and 91 ohm resistors in series with the Data In and Data Out pins – these apparently help prevent ‘ringing’ on the data bus. Check the video for his radical soldering method. Each SMD LED was clamped in a machine shop vice, and the other three parts with their leads preformed were soldered directly to the LED pins.

The other tedious task was planning and laying out the wiring harness. Sets of 10 LEDs were first wired up on the shop bench. He then tacked them up to the ceiling and soldered them to the 14 gauge main harness. The final part was to put up the suspended ceiling and close the 2 sq. ft. grids with opaque plastic.

[dennis1a4] did some trials to figure out the right distance between each LED and the panel to make sure they were illuminated fully without a lot of light bleeding in to adjacent panels. This allowed him to get away without using baffles between the tiles.

Check out the video to see a cool time-lapse of the whole build.

Continue reading “RGB LED Ceiling Display” →

Madeline Gannon The Robot Tamer!

December 20, 2015 by James Hobson 40 Comments

Let’s be honest. Who doesn’t want an industrial six-axis robot arm in their garage to do their bidding? Introducing [Madeline Gannon], the Robot Tamer!

The only tricky part is… if you received an industrial six-axis robot arm, would you be able to control it to do your bidding (easily)? Having taken robotics courses myself in college, and worked with ABB robots like this one, I can tell you, it’s not exactly plug-and-play. Yeah, there’s the teach pendant and you can pretty quickly teach the robot to do a repetitive task well, but unless you’re setting up your own mini manufacturing line — what’s the point? You’re going to want to inject some CNC code or something and have it carve you a sculpture! Or pour you a mixed drink I guess…

Maybe [Madeline] has the answer. Working as an artist in residence at Pier 9, she’s created wearable markers and a motion capture system that allows a giant ABB robot to see, and respond to your movements in a shared space.

Continue reading “Madeline Gannon The Robot Tamer!” →