Stewart Platform Reinvents The Wheel So You Don’t Have To

StewartPlatform

[Dan Royer] has noticed that most university projects involving a Stewart platform spend more time building a platform than on the project itself. He hopes to build a standard platform universities can use as the basis for other projects.

Stewart platforms are six degree of freedom platforms often seen hefting flight simulators or telescopes. The layout of the actuators allows movements in X,Y,and Z as well as pitch, roll and yaw. While large platforms often use hydraulic systems to accelerate heavy loads quickly. [Dan] is looking at a smaller scale system. His platform is built of laser cut wood and uses six steppers to control motion.

One of the harder parts in designing a platform such as this is creating a mechanical system that is strong, precise, and smooth. With so many linkages, it’s easy to see how binding joints could bring the entire thing to a grinding halt. [Dan] is currently using RC helicopter ball joints, but he’s on the lookout for something even smoother.

Continue reading “Stewart Platform Reinvents The Wheel So You Don’t Have To”

A Touch Screen Geiger Counter Without A Geiger Tube

geiger

We’re assuming [Toumal] was desperately bored one day, because in the depths of the Internet he found some really cool components to build a solid state Geiger counter.

The Arduino and touchscreen are rather standard fare [Toumal] picked up on eBay for about $30. What really sets this project apart from all the other geiger counter builds we’ve seen is the solid state geiger counter [Toumal] used. This device uses a specially-made photodiode made by First Sensor to detect gamma emissions from 5 to 1000 keV.

[Toumal] put all the software for his Arduino touch screen radiation detector up on github. To be honest, we’re really impressed with the rad sensor [Toumal] used for this project, so if you ever decide to pick one of those up, he’s got your back with an Arduino library for it.

Using Google Authenticator With An Arduino

Google Authenticator is an app that generates one time passwords (OTPs). These passwords are often used as a second factor of authentication, along with your normal password. OTPs work by having a shared secret and a synchronized clock on two devices. When you generate the password, a hash based on the secret and timestamp is created. This proves that you have access to the secret, and can only be used once.

To secure his Lego mini-figures, [Luca] built an authentication system using Google Authenticator and Arduino. A web app is used to generate a secret that can be configured into the Arduino using an array, and into Google Authenticator using a QR code. The Arduino is using a library that implements Time-based One Time Password authentication (TOTP).

There are some challenges, including keeping a good clock source on the Arduino, but this look like an interesting way to do authentication. After the break, watch a quick video overview of the project (for English captions, hit the CC button).

Continue reading “Using Google Authenticator With An Arduino”

Adding A Display To A USB Digital Scale

arduino_scale

[Oleg] found himself in possession of a Stamps.com Model 510 5lb digital scale.  It’s a great scale, but only works as a USB HID device. In other words, it’s a digital scale without a digital display. He decided he wanted it to be more standalone, so he added a Toshiba HD44780 (compatible) display. An Arduino UNO and USB Host shield were used to make it happen. His sketch simply polls the scale and outputs the weight on the display.

In this case, he used the USB Host Shield from Circuits at Home, but a brief look shows they use the same MAX3421 controller chip as Sparkfun and other versions of the board. You might also be able to pull off the same functionality with an AVR running V-USB, though admittedly it wouldn’t be so easy.

We haven’t found a great way to add USB host mode to projects other than shields like the one [Oleg] used. If you know of a better way, share your ideas in the comments.

Of course, if this isn’t hardcore enough for you, forget using a consumer scale – make your own from scratch!

The Arduino YUN. YUN Means Cloud.

For the longest time, the creators of the Arduino have been looking at how to bring the Arduino platform into the cloud. Ethernet and WiFi shields technically work, but if you’re processing data scraped from a web page, a lowly microcontroller really isn’t the best option. Enter the Arduino YUN. At its core, it’s a regular old Arduino Leonardo. Underneath that metal plate on the board? That’s an SoC running Linux.

Basically, the Linux side of the Yun is pretty similar to a WiFi router running OpenWRT. There’s a USB port for plugging in peripherals, native WiFi support (802.11n, even!), an Ethernet connector, and enough RAM to do all the interesting stuff a small computer connected to the Internet can do.

To make all this web programming easier for Arduino neophytes, the YUN also includes a ‘bridge’ library that automates HTTP transactions between the Linux and microcontroller sides of the YUN. There’s also support for Temboo, an SDK for dozens of APIs that interact with Facebook, Dropbox, FedEx, and hundreds of other web services.

Below you can check out [Massimo] and [David] showing off their wares and going over how the YUN connects to the Internet and interacts with the microcontroller over the ‘bridge’. It’s an interesting device, and something we’ll surely check out at the World Maker Faire.

Continue reading “The Arduino YUN. YUN Means Cloud.”

NES: Nixie Entertainment System

nixieNES

[Bradley W. Lewis] is no stranger to Nixie clock builds, and he felt his latest commission was missing something. Instead of merely mounting the Nixie clock into a case resembling an NES console, he goes full tilt and makes it into an NES console emulator. After some work on the milling machine, a wooden box has room to squeeze in a few new components. [Bradley] originally planned to mount only an Arduino with an ArduNIX shield to handle the Nixie clock, but the emulator demands some space saving. Flipping the Arduino on its side freed up plenty of room and the shield still easily connects to the adjacent Nixie tube board.

A Raspberry Pi serves as the console emulator and was mounted close to the side of the case to allow access to its HDMI port. The other ports from both the Arduino and RasPi stick out of the back, including an extension to the Pi’s RCA video out and buttons to set both the hour and minutes of the clock. The two surplus NES buttons on the front of the case control power to the RasPi and provide a reset function for the Nixie clock.

If that isn’t enough Nixie to satisfy you, check out the WiFi Nixie counter.

Game Of Light

gameoflight

Hyperrealistic graphics may be the standard for gaming, but Game of Light (Warning: Loud video volume) is a welcomed detour into vivid, low-res delight. Built for a course at the University of Oslo by [Abdimaalik], [Martin], [Andre], [Eivind], and [Stian], Game of Light has a handful game options, some of which allow up to four players. The build uses eight DE-DP14211 LED dot matrix boards, each with 32×16 bi-color LEDs and a built-in HT1632C display controller to handle the multiplexing. They are mounted together to form the 64×64 resolution display.

The box was custom-made out of what we suspect is acrylic, and uses some 3D printed pieces to offset the top from the bottom and to hold components in place. SNES controllers send data to the Arduino, which also runs the games and feeds the display controllers. Buried in the mix are two fans to keep the components cool. Everything is open source, so race to Github for source code and the games.

For another LED matrix project with a lot of gaming potential, check out [Brad’s] PS2 mouse interface that lets him interactively draw in real-time.

Continue reading “Game Of Light”