Author: Dan Maloney

Colorful, Touch-Sensitive Light Table is Ready for Gaming

December 26, 2016 by No comments

It’s an ambitious build for sure — you don’t start with $500 worth of wood if you don’t intend for the finished product to dazzle. And this 240-pixel touch-sensitive light box coffee table does indeed dazzle.

Sometimes when we see such builds as these, fit and finish take a back seat to function. [dasdingo89] bucks that trend with a nicely detailed build, starting with the choice of zebrawood for the table frame. The bold grain and the frosted glass top make for a handsome table, but what lurks beneath the glass is pretty special too. The 240 WS2812 modules live on custom PCBs, each thoughtfully provided with connectors for easy service. There’s also an IR transmitter-receiver pair on each board to detect when something is placed over the pixel. The pixel boards are connected to custom-built shift register boards for the touch sensors, and an Arduino with Bluetooth runs the whole thing. Right now the table just flashes and responds to hand gestures, but you can easily see this forming the basis of a beautiful Tetris or Pong table.

This build reminds us a little of this pressure-sensitive light floor we featured recently, which also has some gaming possibilities. Maybe [dasdingo89] and  [creed_bratton_] should compare notes and see who can come up with the best games for their platform.

[via r/DIY and a tip from emptycanister]

IoT-ifying an Old LED Signboard

December 26, 2016 by 6 Comments

Scrolling LED signs were pretty keen back in the day, and now they’re pretty easy to come by on the cheap. Getting a signboard configured for IoT duty can be tricky, but as [kripthor] shows us, it’s not that bad as long as security isn’t your top concern and you can tweak a serial interface.

dec-16-2016-10-57-pm-edited[kripthor] chanced upon an Amplus AM03127 signboard that hails from the days when tri-color LEDs were the big thing. The unit came with a defunct remote thanks to leaking batteries, but a built-in serial interface offered a way to connect. Unfortunately, the RS-232 standard on the signboard wants both positive and negative voltages with respect to ground to represent the 1s and 0s, and that wouldn’t work with the ESP8266 [kripthor] was targeting. The ubiquitous MAX-232 transceiver was enlisted to convert logic levels to RS-232 signals and a small buck converter was added to power the ESP. A little scripting and the signboard is online and ready for use and abuse by the interwebz — [kripthor] says he’ll regret this, but we’re pleased with the way the first remote access turned out. Feel free to check out the live video feed and see what the current message is.

Personally, we don’t have much use for a signboard, but getting RS-232 devices working in the Arduino ecosystem is definitely a trick we’ll keep in mind. If asynchronous serial protocols aren’t your strong suit, you might want to check out this guide to what can go wrong by our own [Elliot Williams].

Modified Servo Adds Focus Control to Telescope

December 26, 2016 by 8 Comments

Scanning the heavens with a telescope is a great way to spend long, clear winter nights, but using a manual telescope can get to be a drag. A motorized mount with altitude and azimuth control is basic equipment for the serious observer, but adding a servo to control the focus of your telescope is one step beyond your average off-the-shelf instrument.

Having already motorized the two axes of the equatorial mount of his modest telescope as a senior project, [Eric Seifert] decided to motorize the focus rack as well. His first inclination was to use a stepper motor like he did on the other two axes, but with a spare high-torque servo at hand, he hacked a quick proof-of-concept. The servo was modified for continuous rotation in the usual way, but with the added twist of replacing the internal potentiometer with an external linear pot. Attached to the focus tube, the linear pot allows [Eric] to control the position and speed of the modified servo. Sounds like controlling the focus will be important to [Eric]’s planned web interface for his scope; we’ll be looking for details on that project soon.

We like the simplicity of this solution, and it’s a trick worth keeping in mind for other projects.  But if fancy steppers and servos aren’t your thing, fear not — astrophotography is as easy as slapping a couple of boards together with a hinge.

Continue reading “Modified Servo Adds Focus Control to Telescope” →

Raspberry Pi and Alexa Make Teddy Ruxpin Smarter than the Average Bear

December 24, 2016 by 8 Comments

Behold the unholy union of Amazon’s Alexa and that feature-limited animatronic bear from the 80s, Teddy Ruxpin. Alexa Ruxpin?

As if stuffing Alexa inside a talking fish weren’t bad enough, now Amazon’s virtual assistant can talk to you through the creepy retro plush thanks to [Tinkernut]’s trip down memory lane. Having located a Teddy Ruxpin on eBay for far less than the original $70 that priced it out from under his childhood Christmas tree, [Tinkernut] quickly learned that major surgery would be necessary to revive the Ruxpin. The first video below shows the original servos being gutted and modern micro servos grafted in, allowing control of the mouth, eyes, and nose via an Arduino.

With the bear once again in control of its faculties, [Tinkernut] embarked on giving it something to talk about. A Raspberry Pi running AlexaPi joined the bear’s recently vacated thorax with the audio output split between the bear’s speaker and the analog input on the Arduino. The result is a reasonable animation, although we’d say a little tweaking of the Arduino script might help the syncing. And those eyes and that nose really need to get into the game as well. But not a bad start at all.

This isn’t the first time that Teddy Ruxpin has gone under the knife in the name of hacks, and it likely won’t be the last. And the way toy manufacturers are going, they might just beat us hackers to the punch.

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Dead-Bug Logic Probe in a Magic Marker

December 24, 2016 by 11 Comments

Logic probes are simple but handy tools that can be had for a couple of bucks. They may not be the sexiest pieces of test gear, nor the most versatile, but they have their place, and building your own logic probe is a great way to understand the tool’s strength and weaknesses.

[Jxnblk]’s take on the logic probe is based on a circuit by [Tony van Roon]. The design hearkens back to a simpler time and is based on components that would have been easy to pick up at any Radio Shack once upon a time. The logic section is centered on the venerable 7400 quad 2-input NAND gate in the classic 14-pin DIP format. The gates light separate LEDs for high and low logic levels, and a 555 timer chip in a one-shot configuration acts as a pulse stretcher to catch transients. The DIP packages lend themselves to quick and dirty “dead bug” construction, and the whole thing fits nicely into a discarded marking pen.

dead-bug-logic-probe-in-marker-body

It’s a simple build and a nice form factor for a useful tool, but for an even slimmer package like an old syringe you’ll probably have to go with SMD components. And when you graduate from the simple logic probe, you might want to check out the capabilities of this smart probe.

Cat vs. Human Escalates with Armor-Plated Feeder

December 23, 2016 by 16 Comments

Wars generally increase innovation as the opposing sides try to kill each other in ever more efficient ways. Even the soft war waged daily between felines and their human servants results in innovation, to wit we offer this armor-plated automated cat feeder.

The conflict between [Sprocket H.G. Shopcat] and her human [Quinn Dunki] began with a thoughtfully provided automatic food dispenser. Like human vending machine customers who witness a just-purchased bag of Cheesy Poofs dangling on the end of the dispense auger, [Sprocket] learned that the feeder would dispense a few fishy nuggets when nudged. [Quinn] embarked on an iterative design process to control [Sprocket]’s off-schedule snacking. Fastening the feeder firmly to the floor, and adding obstructions to prevent her from pawing up the dispense chute — nothing seemed to stop the clever feline’s raids. [Quinn] then pulled out all the stops and whipped up a [Sprocket]-safe enclosure for the feeder from 1/8″ plate steel and copper. This seems to have put the cat back on the straight and narrow, and it doesn’t look half bad either.

All kidding aside, [Quinn]’s approach to this problem is pretty instructive. Careful observations informed several cycles of reasonable modifications until it became clear that only the most extreme solution would work. There’ve been tons of cat feeders here before, from the simple to the complex, but we think all would fall prey to the clever [Sprocket] without a little up-armoring.

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Light Pipes and LEDs Team Up for a Modern Take on the Nixie Tube

December 22, 2016 by 34 Comments

There’s no doubting the popularity of Nixie tubes these days. They lend a retro flair to modern builds and pop up in everything from clocks to weather stations. But they’re not without their problems — the high voltage, the limited tube life, and the fact that you can have them in any color you want as long as it’s orange. Seems like it might be time for a modern spin on the Nixie that uses LEDs and light pipes. Meet Nixie Pipes.

Inspired by an incandescent light-pipe alphanumeric display from a 1970s telephone exchange, [John Whittington]’s design captures the depth and look of a Nixie by using laminated acrylic sheets. Each layer is laser etched with dots in the shape of a character or icon, and when lit from below by a WS2812B LED, the dots pick up the light and display the character in any color. [John]’s modular design allows one master and an arbitrary number of slaves, so large displays can simply be plugged together. [John] is selling a limited run of the Nixie Pipes online, but he’s also open-sourced the project so you can build your own modules.

We really like the modularity and flexibility of Nixie Pipes, and the look is pretty nice too. Chances are good that it won’t appeal to the hardcore Nixie aficionado, though, in which case building your own Nixies might be a good project to tackle.

Continue reading “Light Pipes and LEDs Team Up for a Modern Take on the Nixie Tube” →