Hackaday Prize Entry: Safety Glasses Are Also Hands-Free Multimeter

June 4, 2017 by Bryan Cockfield 23 Comments

It seems like the multimeter is never easy to see during a project. Whether it’s troubleshooting a vehicle’s electrical system and awkwardly balancing the meter on some vacuum lines and the intake manifold, or installing a new solar panel and hoping the meter doesn’t fall on the ground while the leads are in both hands, it seems like there’s never a good way to see the meter while actually using it. Some meters have a small magnet and strap that can be used to hang them temporarily, but this will only get you so far.

[Alain Mauer]’s entry into the Hackaday Prize looks to solve this glaring problem. Using a heads-up Bluetooth display mounted to a pair of safety glasses, a multimeter can be connected to the device in order to display its information directly to its user. Based on his original idea which used a normal pair of prescription glasses as its foundation, [Alain]’s goal is to reduce safety hazards that might arise when using a multimeter in an awkward or dangerous manner that might not otherwise be possible.

The device uses an Arduino Pro Micro to connect to the multimeter and drive the display. [Alain] notes that the real challenge is with the optical system, however. Either way though, this would be a welcome addition to any lab, workspace, or electrician’s toolbox. Be sure to check out the video of it in action after the break.

Continue reading “Hackaday Prize Entry: Safety Glasses Are Also Hands-Free Multimeter” →

E-ink Display Driven DIY

April 20, 2017 by Elliot Williams 44 Comments

E-ink displays are awesome. Humans spent centuries reading non-backlit devices, and frankly it’s a lot easier on the eyes. But have you looked into driving one of these critters yourself? It’s a nightmare. So chapeau! to [Julien] for his FPGA-based implementation that not only uses our favorite open-source FPGA toolchain, and serves as an open reference implementation for anyone else who’s interested.

Getting just black and white on an E-ink display is relatively easy — just hit the ink pixels with the same signal over and over until they give up. Greyscale is made by applying much more nuanced voltages because the pixels are somewhat state-dependent. If the desired endpoint is a 50% grey, for instance, you’d hit it with a different pulse train if the pixel were now white versus if it were now black. (Ever notice that your e-book screen periodically does a white-black flash? It’s resetting all the pixels to a known state.) And that’s not even taking into account the hassles with the various crazy voltages that E-ink displays require, which [Julien] wisely handed off to a dedicated chip.

In the end, the device has to make 20-50 passes through the screen for one user-visible refresh. [Julien] found that the usual microcontrollers just weren’t capable of the speed that he wanted, hence the FPGA and custom waveform tables. We’ve seen E-ink hacks before, and [Julien] is standing on the shoulders of giants, most notably those of [Petteri Aimonen] and [Sprite_tm]. [Julien]’s hack has the fastest updates we’ve ever seen.

We still can’t wait for the day that there is a general-purpose E-ink driver chip out there for pennies, because nearly every project we make with a backlit display would look better, and chew through the batteries slower, with E-ink. In the meantime, [Julien]’s FPGA implementation is pretty close, and it’s fully open.

Continue reading “E-ink Display Driven DIY” →

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!” →

An Ugly But Functional Pi Laptop

March 11, 2017 by Dan Maloney 17 Comments

It’s got a face only its mother could love. Or a Hackaday writer, since this ugly e-waste laptop proudly sports a Jolly Wrencher on its back.

All joking aside, this is a great example of doing what you can with what you’ve got. [starhawk] is limited on funds, and a regular laptop is beyond his means. But being light in the wallet is no reason to go without when you can scrounge parts from friends and family. The base of the laptop is a mini USB keyboard, with the top formed mainly by a 7″ HDMI panel. The back of the display is adorned with a Raspberry Pi 3, a USB hub, a little sound dongle, and the aforementioned Jolly Wrencher. The whole thing is powered by a cast-off power supply brick — no exploding batteries to worry about!

Other Pi-based laptops we’ve covered may be sleeker, but we’ve got to admit that [starhawk]’s keyboard is probably the better choice for working on the next great American novel. And a Linux laptop for next to nothing? That’s a win in our book.

Old Thermometer Gets New Eyes

February 24, 2017 by Bryan Cockfield 14 Comments

As much as we’d like to have the right tools for the right job all of the time, sometimes our parts drawers have other things in mind. After all, what’s better than buying a new tool than building one yourself from things you had lying around? That’s at least what [Saulius] must have been thinking when he needed a thermometer with a digital output, but only had a dumb, but feature-rich, thermometer on hand.

Luckily, [Saulius] had a webcam lying around as well as an old thermometer, and since the thermometer had a LCD display it was relatively straightforward to get the camera to recognize the digits in the thermometer’s display. This isn’t any old thermometer, either. It’s a four-channel thermometer with good resolution and a number of other useful features (with an obvious lack of communications abilities), so it’s not something that he could just overlook.

Once the camera was mounted to an arm and pointed at the thermometer’s screen, an algorithm running on a computer detects polygons and reports its information into a CSV file. This process is made simpler by the fact that LCD screens like this are very predictable. From there, the data is imported into LibreOffice and various charts and graphs can be made.

Although perhaps not the most elegant of hacks, sometimes you have to work with the supplies that are on hand at the time. Sometimes the tools you need are too expensive, politically dangerous, or too impractical to obtain. To that end [Saulius]’s hack is a great example of what hacks are possible with the right mindset.

Smoothly Modernized Nixie Display

January 14, 2017 by James Hobson 37 Comments

The renaissance of Nixie tube popularity amid the nostalgia surrounding older tech has made them almost prohibitively expensive for individual projects. Seeing an opportunity to modernize the beloved devices, [Connor Nishijima] has unleashed this new, LED edge-lit display that he has dubbed Lixie.

We featured his prototype a few years ago. That design used dots to make up each character but this upgrade smooths that out with sleek lines and a look one would almost expect from a professional device — or at the very least something you’d see in a cyberpunk near-future. The color-changing Neopixel LEDs — moderated by a cleverly designed filter — allow for customization to your heart’s content, and the laser-cut acrylic panes allow for larger displays to be produced with relative ease.

The image above (and the video below) show two revisions of the most recent Lixie prototypes. There is a huge improvement on the right, as the digits are now outlines instead of single strokes and engraved instead of cut completely through the acrylic. The difference if phenomenal, and in our opinion move the “back to the drawing board” effect to “ready for primetime”. [Connor] and his team are working on just that, with a Tindie preorder in place for the first production-ready digits to roll off their line.

Continue reading “Smoothly Modernized Nixie Display” →

Massive Pixel Display Holiday Decoration

December 20, 2016 by James Hobson 15 Comments

Decorating for the holidays is serious business! Finding themselves surrounded by neighbours who go big, redditor [wolfdoom] decided that this was the year to make a strong showing, and decided to build an oversized pixel LED display.

Demonstrating resourcefulness in their craft, [wolfdoom] found an old fluorescent light grid pattern to prevent bleed from one pixel to the next. Reusing this grid saves many hours of precision-cutting MDF — to be substituted with many hours of cutting the plastic with decidedly more room for error. Attaching the resulting grid to a sheet of plywood, and 576(!) drilled holes later, the LEDs were installed and laboriously wired together.

A Plastic light diffusing sheet to sell the pizel effect and a little help from their local maker space with the power circuit was enough to keep this project scrolling to completion — after the requisite period of basement-dwelling fabrication.

Despite some minor demotion attributed to a clumsy daughter, the massive 4×4 display remained a suitably festive decoration. For now the control system remains in [wolfdoom]’s basement, but with plans to incorporate it into the display’s frame down the road.

One of the more interesting LED matrix builds we saw this year is the one that uses 1575 beer bottles. For a more interactive holiday decorations, Halloween usually takes the cake — like this animated door knocker.

[via /r/DIY]