Calcuino Is An Arduino Calculator

June 28, 2020 by Al Williams 4 Comments

All by itself, a calculator based on an Arduino isn’t necessarily very novel. However, [Danko Bertović] of Volos Projects has a nice board that, of course, looks like a calculator. There are 16 keys and an LED display. But it seems to us the real value would be using this as a base for other projects.

As an inexpensive development board, it’s handy to have a simple processor with a keyboard and a display. There’s some extra I/O pins and the first example in the video below shows using the setup as a simple organ, for example. We’d love to see an option to replace the LED with an LCD and maybe even some different CPU options, as well.

The board is essentially an Arduino with a standard USB to serial chip and a MAX7219 display driver. Of course, you could breadboard up all of these things, but it wouldn’t be as neat looking. One unusual thing about the keyboard is that it is not multiplexed. Each button has a label that indicates what Arduino pin it connects with. So key 6 connects to pin 6 and pin A2 connects to the key marked =/A2.

With the availability of inexpensive PC boards, we’re seeing many nice designs out there that would be easy to repurpose for other things. For example, we thought this board would easily run the Kim Uno, with some modifications to the I/O routines. Might even be able to work out a clone of an even older computer to fit on the board.

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DIY TV-B-Gone Is A-OK

June 25, 2020 by Kristina Panos 49 Comments

Where won’t they put a TV these days? We’ve even seen one creeping behind semi-transparent mirror film in the ladies’ room of a sports bar, though that one didn’t last long. Up until that moment, we had never wished so hard for a TV-B-Gone, especially one as small and powerful as this DIY version by [Shane].

The best thing about [Shane]’s DIY TV-B-Gone is the strength of signal, though the size is nothing to sneeze at. That’s a 10-watt array or IR LEDs out of a security camera, and you can see how much brighter it is than a single IR LED in the video after the break.

Packed inside this minty enclosure is an Arduino Nano, which holds all the TV power-off codes known to hackers and fires them off in quick succession. [Shane] salvaged a MOSFET from an electronic speed controller to drive that LED array, and there’s a voltage booster board to raise the 3.7V lithium battery to 5V. [Shane] hasn’t really had the chance to test this out in public what with the global pandemic and all, but was able to verify a working distance of 40 feet inside the house.

Don’t care for such a raw look? Hide your zapper inside a toy, like this sonic screwdriver version.

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Tracked Robot Makes Sand Drawings

June 24, 2020 by Al Williams 6 Comments

[Ivan] seems to enjoy making 3D printed vehicles with tracks. His latest one uses 50 servo motors to draw patterns in the sand at the beach. You can see it work in the video below. Well, more accurately you can see it not work and then work as the first iteration didn’t go exactly as planned.

An Arduino Mega 2560 provides the brains and the whole unit weighs in at almost 31 pounds, including the batteries. We didn’t see Ivan’s design files, although it wouldn’t be hard to do your own take on the robot.

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Score Big Against Boredom With Tabletop Bowling

June 21, 2020 by Kristina Panos 18 Comments

Bowling has been around since ancient Egypt and continues to entertain people of all ages, especially once they roll out the fog machine and hit the blacklights. But why pay all that money to don used shoes and drink watered-down beer? Just build a tabletop bowling alley in your spare time and you can bowl barefoot if you want.

Those glowing pins aren’t just for looks — the LEDs underneath them are part of the scoring system. Whenever a pin is knocked out of its countersunk hole, the LED underneath is exposed and shines its light on a corresponding light-dependent resistor positioned overhead. An Arduino Uno keeps track of of the frame, ball number, and score, and displays it on an LCD.

The lane is nearly six feet long, so this is more like medium-format bowling or maybe even skee-bowling. There are probably a number of things one could use for balls, but [lainealison] is using large ball bearings. Roll past the break to see it in action, but don’t go over the line!

Can’t keep your balls out of the gutter? Build a magic ball and make all wishful leaning more meaningful as you steer it down the lane with your body.

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Message In A Bottle: Bicycle Trailer On A Mission

June 19, 2020 by Sven Gregori 18 Comments

Graffiti is a controversial subject, and whether you see it as art or vandalism usually depends where and how you come across it. From the scribbled tag on a house wall, to highly sophisticated murals, they tend to have one thing in common though: making a statement — whether that’s political, showing appreciation, or a simple “I was here”. [Sagarrabanana] had his own statement to make, but chose a less permanent way to express himself with his type of graffiti.

Unhappy about the lack of dedicated cycle lanes in his area, he built an automatic, Arduino-controlled water dispensing bicycle trailer, writing his message on every street he rides on. The build is documented in a video, and shown in action in another one — which are both in Spanish (and also embedded after the break), but pictures are worth their thousand words in any language.

Inspired by persistence of vision (POV), where moving LEDs sync up their blinking to give the illusion of a static image, [Sagarrabanana] transformed the concept to water on a road using an array of solenoids attached to a water tank. Each solenoid is controlled by a relay, and a predefined font determines when to switch each relay — the same way pixels on a display would be set on or off, except small amounts of water are squirted out as the bicycle is moving along. The message itself is received via serial Bluetooth module, and can be easily modified for example from a phone. To adjust the water dispensing to the cycling speed, the whole system is synced to a magnetic switch mounted to one of the trailer’s wheels, so you could theoretically take it also with you on a run.

Time will tell if [Sagarrabanana]’s mission has the success he hopes for, but there’s no doubt the trailer will attract attention anywhere he goes. Well, we wish him all the best to get the message through without requiring a too drastic alternative as writing medium. Although, we’ve seen a graffiti robot that uses chalk spray in the past, so there’s certainly room for a not-too-permanent upgrade if needed.

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Capture The Flag, Along With The Game Data

June 18, 2020 by Kristina Panos 7 Comments

With events of all sizes on hold and live sports mostly up in the air, it’s a great time to think of new ways to entertain ourselves within our local circles. Bonus points if the activity involves running around outside, and/or secretly doubles as a team-building exercise, like [KarelBousson]’s modernized version of Capture the Flag.

Much like the original, the point of this game is to capture the case and keep it for as long as possible before the other team steals it away. Here, the approach is much more scientific: the box knows exactly who has it and for how long, and the teams get points based on the time the case spends in any player’s possession.

Each player carries an RFID tag to distinguish them from each other. Inside the case is an Arduino Mega with a LoRa shield and a GPS unit. Whenever the game is afoot, the case communicates its position to an external Raspi running the game server.

If you haven’t met LoRa yet, check out this seven-part introductory tutorial.

Arduino Magnetic Board Is Anything But Boring

June 17, 2020 by Kristina Panos 3 Comments

Magnets (especially those ball magnets!) are endlessly fascinating, aren’t they? It’s almost dangerous to combine them with LEDs, because how are you supposed to get anything done with something like [andrei.erdei]’s Arduino Magnetic Board beckoning from beyond your keyboard?

This tons-of-fun board uses ball magnets to light up RGB LEDs as they roll around on the sexy Plexiglas field. Underneath the LED matrix is an orchestra of 36 reed switches — those little glass gas-filled grains of rice with axial leads that snap together or fly apart in the presence of magnetic fields. The LEDs are controlled with an Arduino Pro Mini, and so is the 8Ω speaker for sound effects.

[andrei.erdei] has already developed a few applications for this delightful desk toy, and they’re all on GitHub. There’s a chase game that involves tilting the board to catch the next red dot with the magnet, a light painting game, and a sequencer that mimics the ToneMatrix. Roll past the break to check out the series of short demo videos.

Want to play with reed switches but can’t source any at the moment? You could just make them yourself.

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