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Bigger isn’t always better, as illustrated nicely by this device from YouTuber “Volos Projects.” It’s not only physically quite small, squeezing an Arduino into a 40x25x25mm aluminum enclosure, but uses an interface consisting of a single button (plus a power switch). Data output is handled via a similarly tiny 64×48 pixel OLED display.

Regardless of its minuscule size and binary input method, it can still be utilized for a variety of functions, including as a stopwatch or counter, or even to play Flappy Bird. 

Demonstration and build footage can be seen in the clip below, while a parts list, code, and electrical diagram can be found in the video’s description.

When building projects with a simple goal in mind, it’s not unheard of for us to add more and more switches, buttons, and complexity as the project goes through its initial prototyping stages. Feature creep like this tends to result in a tangled mess rather than a usable project. With enough focus, though, it’s possible to recognize when it’s happening and keep to the original plans. On the other hand, this single-button project with more than one use seems to be the opposite of feature creep. (YouTube, embedded below.)

[Danko]’s project has one goal: be as useful as possible while only using a single button and a tiny screen. Right now the small handheld device can be used as a stopwatch, a counter, and can even play a rudimentary version of flappy bird. It uses an Arduino Pro Mini, a 64×48 OLED screen running on I2C, and has a miniscule 100 mAh 3.7V battery to power everything. The video is worth watching if you’ve never worked with this small of a screen before, too.

Getting three functions out of a device with only one button is a pretty impressive feat, and if you can think of any other ways of getting more usefulness out of something like this be sure to leave it in the comments below. [Danko] is no stranger to simple projects with tiny screens, either. We recently featured his homebrew Arduino calculator that uses an even smaller screen.

In the build shown below, Evan McMahon dares to ask the question, “Have you ever been disappointed by a mood ring?” While that might seem a bit random, the answer is a likely “yes” if you’ve ever worn one with the expectation of any sort of accuracy. Fortunately, he didn’t just pose the question, but also came up with a clever solution, using an array of lights under Arduino control.

For the setup, McMahon uses the camera on his iPhone to take video of his smiling or frowning mug, then analyzes it with the help of Unity running on a computer to translate this into his apparent state of mind.

This info is then sent to an Arduino Uno, which puts the programmable LED lights into dance mode if he’s happy, and makes them shine blue if he’s a bit blue himself!

As first reported by the Des Moines Register, this year 14-year-old Josiah Davenport decided to animate 3,500 Christmas lights on his family’s home with the help of an Arduino Mega. The lighting pattern is synchronized with the Trans-Siberian Orchestra’s “Wizards in Winter,” which passersby can listen to by tuning in to 89.5 FM on their car radios. 

This ambitious installation was started back in July, and took around 100 hours of research, programming, and assembly. How the lights look at night can be seen in the first video below, while the second and third outline how everything was assembled.

Davenport notes that it’s been a fun endeavor, but is happy to see it come together, hoping that it brings a smile to people’s faces this holiday season! You can read more about the project in his local newspaper’s article here.

It’s that time of year again, when many the world over chop down a tree, then insert it into some sort of water dish to keep it green for a month or longer. This normally works out well, but means that someone has to keep it hydrated, climbing under sharp branches to intermittently check the water level.

As originally seen on Reddit, this is a perfect job for Arduino, and with some very simple wiring, maker “Boskovitch” created a clever setup that shows water levels with three blue, yellow, and red LEDs. A depth sensor in inserted into the water, which feeds analog readings to an Arduino Nano that is used for control.

Threw this together last night for my dad. He’s very anal about keeping his tree healthy, and he gets on his stomach and sticks his hand in the base to check the water level a couple of times a day. So I threw this together so he doesn’t have to crawl under the tree anymore. After the semester is over I might add an automatic watering system with a solenoid valve and gravity feed.

Want to recreate this setup for your own Christmas conifer? Check out Boskovitch’s write-up here.

You may have come across the term “PID control,” and while this proportional-integral-derivative control method does a great job of smoothing out oscillations, where does one get started? 

One solution would be Mr Innovative’s demo device, showcased in the video below. In it, a DC gear motor is able to smoothly rotate an arrow overlaid on a protractor by a certain number of degrees.

Input is via a Bluetooth smartphone interface, and an encoder is used for feedback to the commanding Arduino Uno. Everything is fastened together by 3D-printed parts, and if you’d like to try your own PID experiment, code and print files are linked in the video description.

Certain hobbies come in clusters. It isn’t uncommon to see, for example, ham radio operators that are private pilots. Programmers who are musicians. Electronics people who build model trains. This last seems like a great fit since you can do lots of interesting things with simple electronics and small-scale trains. [Jimmy] at the aptly-named DIY and Digital Railroad channel has several videos on integrating railroad setups with Arduino. These range from building a DCC system for about $45 (see below) to a crossing signal.

There are actually quite a few basic Arduino videos on the channel, although most of them are aimed at beginners. However, the DCC — Digital Command and Control — might be new to you if you are a train neophyte. DCC is a standard defined by the National Model Railroad Association.

Model trains pick up electrical power from the rails. DCC allows digital messages to also ride the rail. The signal shifts from positive to negative to indicate marks and spaces. By diode switching the electrical signal, the train or other equipment can get a constant supply of current. However, equipment monitoring the line ahead of the diodes can read the data and interpret it as commands.

To accommodate old equipment, you can stretch the high or low values to make the average voltage either positive (forward) or negative (reverse). This can heat up DC motors, though, so it may shorten the life of the legacy equipment.

The build uses an available Arduino library, so if you want to get into the protocol you’ll have to work through that code. We had to wonder if there were other places where passing power and data on the same lines might be useful. There are other ways to do that, of course, but this would be a reasonable place to start if you needed that capability.

If you want to use an mBed system instead of an Arduino, there’s a great tutorial for that. Either way, it is just the thing for your next coffee table.

Certain hobbies come in clusters. It isn’t uncommon to see, for example, ham radio operators that are private pilots. Programmers who are musicians. Electronics people who build model trains. This last seems like a great fit since you can do lots of interesting things with simple electronics and small-scale trains. [Jimmy] at the aptly-named DIY and Digital Railroad channel has several videos on integrating railroad setups with Arduino. These range from building a DCC system for about $45 (see below) to a crossing signal.

There are actually quite a few basic Arduino videos on the channel, although most of them are aimed at beginners. However, the DCC — Digital Command and Control — might be new to you if you are a train neophyte. DCC is a standard defined by the National Model Railroad Association.

Model trains pick up electrical power from the rails. DCC allows digital messages to also ride the rail. The signal shifts from positive to negative to indicate marks and spaces. By diode switching the electrical signal, the train or other equipment can get a constant supply of current. However, equipment monitoring the line ahead of the diodes can read the data and interpret it as commands.

To accommodate old equipment, you can stretch the high or low values to make the average voltage either positive (forward) or negative (reverse). This can heat up DC motors, though, so it may shorten the life of the legacy equipment.

The build uses an available Arduino library, so if you want to get into the protocol you’ll have to work through that code. We had to wonder if there were other places where passing power and data on the same lines might be useful. There are other ways to do that, of course, but this would be a reasonable place to start if you needed that capability.

If you want to use an mBed system instead of an Arduino, there’s a great tutorial for that. Either way, it is just the thing for your next coffee table.

While we don’t normally think of typing on a computer as a dangerous job, the U.S. Department of Labor reports that workers spend 25,000 hours away from work due to repetitive strain injuries, such as using a computer. Part of this could be due to the fact that the average computer user applies two to seven times the necessary force needed to activate a keyboard’s keys, slamming them down, then experiencing a sudden stop.

In order to help cushion these small blows, researchers Alec Peery and Dušan Sorma at Ohio University have been exploring a mechanical keyboard concept with a 3D-printed dampener built in. Testing has been undertaken using the popular Cherry MX switches, with typing simulated by dropping a 150 gram cylinder from 125mm, then measured using an Arduino Uno and force sensing resistor.

This paper is a demonstration of how 3D printing can be used to create a composite (plastic and rubber) keyboard switch that is ergonomically superior to a traditional injection moulded plastic switch. The prototype switch developed in this project aims to reduce impact forces from keyboard use exerted on user’s fingers by “cushioning” the act of bottoming out the switch during a key press. This concept is significant to industry because it aims to reduce overuse injuries caused from work on computer, a portion of the $20 Billion a year owed in worker compensation in the United States. A commercial Cherry MX keyboard switch has been modified through CAD modelling and 3D printing to incorporate damping regions in the lower half of the switch housing. The switch housings were simultaneously 3D printed with plastic and rubber and their force damping properties were tested with an Arduino UNO microcontroller and force sensing resistor resting on the key tops.

The full research paper is available here.

Aseen here, Bit by Jonghong Park at the University of the Arts Bremen is a beautiful visualization of how everything is linked together using the Markov chain principle. This installation uses an Arduino Mega for control, rotating arms that hold a pair of microswitches around coaxial gear-shaped cylinders.

In the sequence, one arm turns, then lobes on these “gears” that represent a two-bit number push the microswiches. This number is used to choose the following stepper to be turned in the sequence. The next selected arm then rotates in the same manner. This predictable cycle continues on and on clicking in a way that’s related, but not without careful observation.

The installation ‘bit’ represents a natural random process based on the principle of a Markov chain. Each machine consists of “information” engraved on the read head and an “event” caused by the operation of the motor. Machines are linked together based on a Markov chain algorithm to influence events, and eventually we can predict which of the four machines will move in the next turn. The movements of these four machines are shown as a random process, but in fact they are sequence of events. Like an invisible chain, all things and events in our world are connected.

Each of the four machines has its own state, which have been named ( 0,0 / 0,1 / 1,0 / 1,1 ), respectively. Each machine is equipped with a wooden read head with binary information on the surface and a microswitch to read the current state of the read head. The microswitch is connected to the stepper motors located in the center of the machine. A machine whose state is called moves the stepper motors by 1/240 of a degree. The microswitch turns on / off (1/0) along the surface of the read head each time the motor moves and calls the next machine corresponding to the state (2-Bit) of the current position of the read head. At this time, the machine corresponding to the measured state goes through the same process and calls another machine or itself.

These four machines symbolize another system separate from ours. We observe machines separate from the world as if we were watching computer simulations. The binary digits recorded in the read head are the smallest units of unspecified information possible, called bits. The bit, as the smallest particle that can make up the world and not simply as a digital recording unit, symbolizes the basis of this world. The things that we call noise, the information that we think of as meaningless, the information from which we cannot find the pattern, and the information that we cannot decode are called “chance”. When this information can be observed from outside our own world, we have proven through the Markov chain that all events are linked together.

The interplay concept is certainly interesting, and it’s pleasing to watch in the video below from a purely aesthetics point of view as well.



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