Ethanol-Powered Arduinos

April 19, 2017 by Elliot Williams 36 Comments

Following the time-honored YouTube tradition of ordering cheap stuff online and playing with it while the camera runs, [Monta Elkins] bought a Stirling engine that drives a DC motor used as a generator. How much electrical juice can this thing provide, running on just denatured alcohol? (Will it blend?)

The answer is probably not really a spoiler: it generates enough to run “Blink.ino” on a stock Arduino, at least when powered directly through the 5 V rail. [Monta] recorded an open-circuit voltage of around 5 V, and a short-circuit current of around 100 mA at a measured few hundred millivolts. While he didn’t log enough of the points in-between to make a real power curve, we’re guessing the generator might be a better match for 3.3 V electronics. The real question is whether or not it can handle the peaky demands of an ESP8266. Serious questions, indeed!

The video is a tad long, but it’s more than made up for by the sight of an open flame vibro-botting itself across his desk while [Monta] is trying to cool the cold side down with a melting ice cube. Which got us thinking, naturally. If you just had two of the Stirling engines… Continue reading “Ethanol-Powered Arduinos” →

Pi Time – A Fabric RGB Arduino Clock

April 16, 2017 by Pedro Umbelino 4 Comments

Pi Time is a psychedelic clock made out of fabric and Neopixels, controlled by an Arduino UNO. The clock started out as a quilted Pi symbol. [Chris and Jessica] wanted to make something more around the Pi and added some RGB lights. At the same time, they wanted to make something useful, that’s when they decided to make a clock using Neopixels.

Neopixels, or WS2812Bs, are addressable RGB LEDs , which can be controlled individually by a microcontroller, in this case, an Arduino. The fabric was quilted with a spiral of numbers (3.1415926535…) and the actual reading of the time is not how you are used to. To read the clock you have to recall the visible color spectrum or the rainbow colors, from red to violet. The rainbow starts at the beginning of the symbol Pi in the center, so the hours will be either red, yellow, or orange, depending on how many digits are needed to tell the time. For example, when it is 5:09, the 5 is red, and the 9 is yellow. When it’s 5:10, the 5 is orange, the first minute (1) is teal, and the second (0) is violet. The pi symbol flashes every other second.

There are simpler and more complicated ways to perform the simple task of figuring out what time it is…

We are not sure if the digits are lighted up according to their first appearance in the Pi sequence or are just random as the video only shows the trippy LEDs, but the effect is pretty nice:

Continue reading “Pi Time – A Fabric RGB Arduino Clock” →

Hacker U.

April 16, 2017 by Al Williams 7 Comments

If you go to the University of South Florida, you can take the “Makecourse.” The 15-week program promises to teach CAD software, 3D printing, Arduino-based control systems, and C++. Don’t go to the University of South Florida? No worries. Professor [Rudy Schlaf] and [Eric Tridas] have made the entire course available online. You can see several videos below, but there are many more. The student project videos are great, too, like [Catlin Ryan’s] phase of the moon project (see below) or [Dustin Germain’s] rover (seen above).

In addition to a lesson plan and projects, there’s a complete set of videos (you can see a few below). If you are a regular Hackaday reader, you probably won’t care much about the basic Arduino stuff and the basic electronics–although a good review never hurts anyone. However, the more advanced topics about interrupts, SDCards, pin change interrupts might be just the thing. If you ever wanted to learn Autodesk Inventor, there are videos for that, too.

Continue reading “Hacker U.” →

Keep An Eye On The Sky With RDuinoScope

April 11, 2017 by Will Sweatman 7 Comments

We’ve all enjoyed looking up at a clear night sky and marveled at the majesty of the stars. Some of us have even pointed telescopes at particular celestial objects to get a closer view. Anyone who’s ever looked at anything beyond Jupiter knows the hassle involved. It is most unfortunate that the planet we reside on happens to rotate about a fixed axis, which makes it somewhat difficult to keep a celestial object in the view of your scope.

It doesn’t take much to strap a few steppers and some silicon brains to a scope to counter the rotation of earth, and such systems have been available for decades. They are unfortunately quite expensive. So [Dessislav Gouzgounov] took matters into his own hands and developed the rDuinoScope – an open source telescope control system.

Based on the Arduino Due, the systems stores a database of 250 stellar objects. Combined with an RTC and GPS, the rDunioScope can locate and lock on to your favorite nebula and track it, allowing you to view it in peace. Be sure to grab the code and let us know when you have your own rDuinoScope set up!

Wireless Nunchuck R/C Remote!

April 10, 2017 by James Hobson 5 Comments

[Dan], admirably rose to the occasion when his son wanted a new toy. Being a dedicated father — and instead of buying something new — he took the opportunity to abscond to his workbench to convert a Wiimote Nunchuck into a fully wireless controller for his son’s old r/c car — itself, gutted and rebuilt some years earlier.

Unpacking the nunchuck and corralling the I2C wires was simply done. From there, he combined a bit of code, an Arduino pro mini, and two 1K Ohm resistors to make use of an Aurel RTX-MID transceiver that had been lying around. Waste not, want not.

A TI Stellaris Launchpad is the smarts of the car itself, in concordance with a TB6612FNG motor controller. The two Solarbotics GM9 motors with some 3D printed gears give the car some much needed gusto.

Continue reading “Wireless Nunchuck R/C Remote!” →

Everyone Loves Faster ESP8266 TFT Libs

April 8, 2017 by Elliot Williams 24 Comments

Reader [Jasper] writes in with glowing praise for the TFT_eSPI library for the ESP8266 and the various cheap 480×320 TFT displays (ILI9341, ILI9163, ST7735, S6D02A1, etc.) that support SPI mode. It’s a drop-in replacement for the Adafruit GFX and driver libraries, so you don’t need to rework your code to take advantage of it. If you’re looking to drive an LCD screen with an ESP8266 and Arduino, check this out for sure.

As a testbed, [Jasper] ported his Tick Tock Timer project over to the new library. He got a sevenfold increase in draw speed, going from 500 ms to 76 ms. That’s the difference between a refresh that’s visibly slow, and one that looks like it happens instantly. Sweet.

Improving software infrastructure isn’t one of the sexiest or most visible hacks, but it can touch the lives of many hackers. How many projects have we featured with an ESP8266 and a screen? Thanks, [Bodmer] for the good work, and [Jasper] for bringing it to our attention.

Star Trek Desktop Viewer In The Palm Of Your Hand!

April 7, 2017 by James Hobson 8 Comments

There’s building small computers — like the Raspberry Pi — and then there’s building small computers — like this Desktop Viewer from Star Trek.

[Monta Elkins] is using a Beetle for this project; it’s an Arduino clone, hosting the ATMega32U4 microcontroller, with a unique feature that allows you to twist connecting wires to secure them to the board. Instead, [Elkins] went with the logical choice of soldering them. For a display, he used a SPI serial OLED 128 x 64 monochrome screen which he has cycling through a number of iconic Star Trek TOS symbols and animations. The images were converted into PROGMEM — which gets loaded into flash memory — before finally being uploaded to the Beetle.

Following some fine 3D print work in ABS plastic which rendered the Desktop Viewer’s case, [Elkins] used acetone to solvent-weld the pieces together and applied a quick coat of paint to finish it off. This little replica would make a great desktop gadget as it requires a micro-USB to power the device.

Continue reading “Star Trek Desktop Viewer In The Palm Of Your Hand!” →