Raspberry Pi Driven Polargraph Exhibits High Precision Drawing Ability

November 16, 2012 by Mike Szczys 23 Comments

This polar graph draws some amazing shapes on a dry erase board. Part of that is due to the mounting brackets used for the two stepper motors and the stylus. But credit is also due for the code which takes velocity into account in order to plan for the next set of movements.

The Go language is used to translate data into step commands for the two motors. This stream of commands is fed over a serial connection between the RPi board and an Arduino. The Arduino simply pushes the steps to the motor controllers. The inclusion of the RPi provides the horsepower needed to make such smooth designs. This is explained in the second half of [Brandon Green’s] post. The technique uses constant acceleration, speed, and deceleration for most cases which prevents any kind of oscillation in the hanging stylus. But there are also contingencies used when there is not enough room to accelerate or decelerate smoothly.

You can catch a very short clip of the hardware drawing a tight spiral in the video embedded after the break.

Continue reading “Raspberry Pi Driven Polargraph Exhibits High Precision Drawing Ability” →

Adafruit’s Got A New Board, An Official Arduino

November 9, 2012 by Brian Benchoff 21 Comments

There’s a new Arduino in town, this time designed in conjunction with Adafruit. It’s the Arduino Micro, a very neat little board designed for breadboard use.

Ostensibly an upgrade of the long in the tooth Arduino Nano, the new Micro takes all the best features of the new Arduino Leonardo and shrinks them down to a convenient stick of gum-sized package. It’s powered by the ATmega32u4 microcontroller, and with a MicroUSB port is able to emulate keyboards, mice and other USB input devices.

Of course with any microcontroller dev board, comparisons must be drawn between the Arduino Micro and the very popular Teensy USB dev board. Like the Teensy boards (and the new Arduino Leonardo), the Micro is able to function as a USB keyboard or mouse. The Teensys, though, is loaded with LUFA making it able to emulate just about anything from mice, USB audio devices, and MIDI synths.

KegDroid Makes Drinking Beer More Fun

November 8, 2012 by Ryan Fitzpatrick 16 Comments

KegDroid beer arduino

Are you bored with just drinking beer? Are your friends constantly sneaking into your house and stealing your sacred beverages? If so, perhaps you need KegDroid – the Android controlled beer tap created by [Paul Carff].

Looking for a way to add more excitement to drinking his beer, [Paul] spiced up his tap with a little extra technology. He added an Android tablet for touchscreen navigation of the menus, an Arduino to control the flow sensors and solenoid valves, and an NFC reader to act as security for restricted access. Users must be authenticated before they are allowed to pour any alcohol.

Your name and photo are pulled from your Google+ account as you’re logged in, then you simply select your beverage of choice, and if you’d like a one, eight, or twelve ounce pour. Flow sensors automatically shut off when you have the desired quantity.

Seems like you get more foam than beer, but all in all it’s a cool bar top app.

Check out the video after the break.

Continue reading “KegDroid Makes Drinking Beer More Fun” →

Dumpster Diving Nets 100 Arduino-powered Motor Controllers

November 6, 2012 by Brian Benchoff 47 Comments

Never one to pass up the recycle pile at work, [Scott] usually doesn’t find much. A few old hard drives, maybe a ancient laptop every once in a while, but on very rare occasions he finds something actually useful. This latest haul is a gaggle of stepper motor drivers that, with a bit of work, can be reverse engineered and turned into an Arduino.

After prying into one of the plastic-enclosed boards, [Scott] found a LED, a quartet of transistors for powering the motor, and an ATMega168 microcontroller. Interestingly, most of the pins for the 168 were already broken out on the DA15 connector on each controller. The only thing needed was to build a programmer to dump the Arduino bootloader onto these little widgets.

After much trial and error (and building a new programming interface), [Scott] now has 100 Arduinos with a single stepper motor controller built in. He’s already made a toy light cycle rotate on a small stepper (after the break) and blink a LED, but with this many widgets, we’re wondering what crazy contraption [Scott] will come up with.

Continue reading “Dumpster Diving Nets 100 Arduino-powered Motor Controllers” →

Giving The Arduino Deques, Vectors And Streams With The Standard Template Library

October 22, 2012 by Brian Benchoff 20 Comments

The Arduino IDE is extremely similar to C++, but judging from the sketches you can find on the Internet, you’d never know it. Simpler Arduino projects can make do with just toggling IO pins, reading values, and sending serial data between two points. More complex builds fall into the category of real software development, and this is where the standard Arduino IDE falls miserably short.

[Andy] saw this lack of proper libraries for more complicated pieces of software as a terrible situation and decided to do something about it. He ported the SGI Standard Template Library to bring all those fun algorithms and data structures to any AVR chip, including the Arduino.

Going over what’s included in [Andy]’s port reads just like a syllabus for an object-oriented programming class. Stacks, queues, and lists make the cut, as do strings and vectors. Also included is just about everything in the and headers along with a few Arduino-oriented additions like a hardware serial and liquid crystal streams.

With all these objects floating around, [Andy] says it will make an impact on Flash and SRAM usage in an AVR. Still, with all the hullabaloo over faster and larger ARM micros, it’s nice to see the classic 8-bit microcontroller becoming a bit more refined.

The Arduino Due Is Finally Here

October 20, 2012 by Brian Benchoff 81 Comments

After a years-long wait, an ARM powered Arduino is finally due. The Arduino Due will finally be released this coming Monday.

On board the Arduino Due is an Atmel-sourced ARM Cortex M3 microcontroller running at 84 MHz. The Due has an impressive list of features including a USB 2.0 host, compatibility with the Android ADK (lest you still need an IOIO), 12 analog inputs with 12-bit resolution, 2 analog outputs running at 12 bits, a CAN interface, and more input pins than you can shake a stick at.

For a full list of features, you can grab this PDF we picked up when we saw the Due at Maker Faire NYC

This hardware update to the Arduino platform makes a lot of very cool builds very possible for even the beginner hardware hacker. Of course the Due will be used for controlling drones and UAVs, laser cutters and 3D printers, and playing WAV files from the analog outputs. The much improved hardware opens up a lot of other possible builds including making your own guitar pedals – DSP is a wonderful thing – and reading the telemetry from your car in real-time via the CAN bus.

Although it’s not available right now, you will be able to buy an Arduino Due for $49 USD this coming Monday at your favorite electronics retailers.

Halloween Props: Spooky Eyes Light Up The Bushes

October 19, 2012 by Mike Szczys 11 Comments

This is just one example of several pairs of spooky eyes which light up [Vato Supreme’s] bushes this Halloween. The quick and inexpensive build process make it a perfect diy decoration.

Each eye is made up of a ping-pong ball and an LED. But that alone won’t be very spook as the entire ball will glow rather brightly. So he spiced things up a bit by masking off the shape of a pupil and spraying the balls black. The vertical slit seen in white above will glow red like a demon in the night.

The LEDs are driven by an ATtiny85 running the Arduino bootloader. [Vato] found there was plenty of space two write code which fades the eyes in and out using PWM. This happens at random intervals for each of the four pairs he is driving.

We’ve seen a similar project that used oversized LEDs as the eyes. But we really like the idea of using a diffuser like this one. See it in action after the break.

Continue reading “Halloween Props: Spooky Eyes Light Up The Bushes” →