Six-legged robots are nothing new, but if you’d like inspiration for your own, it would be hard to beat this 22 servo-driven, 3D-printed hexapod from Dejan at How To Mechatronics. 

The ant-inspired device features three metal geared servos per leg, as well as a pair to move the heat, another for the tail, and a micro servo to activate the mandibles.

To control this large number of servos, Dejan turned to the Arduino Mega, along with a custom Android app and Bluetooth link for the user interface. While most movements are activated by the user, it does have a single ultrasonic sensor buried in its head as “eyes.” This allows it to lean backwards when approached by an unknown object or hand, then strike with its mandibles if the aggressor continues its advance. 

As the name suggests, the hexapod has six legs but in addition to that, it also has a tail or abdomen, a head, antennas, mandibles and even functional eyes. All of this, makes the hexapod look like an ant, so therefore we can also call it an Arduino Ant Robot.

For controlling the robot I made a custom-built Android application. The app has four buttons through which we can command the robot to move forward or backwards, as well as turn left or right. Along with these main functions, the robot can also move its head and tail, as well as it can bite, grab and drop things and even attack.

You can see it in action and being assembled in the video below, and build files are available here.

LED strips reacting to sound is nothing new; however, Paul Shulman’s setup does things a bit differently. Instead of responding to the tune’s overall volume, one musical frequency is analyzed and averaged; if the intensity changes sufficiently on that particular frequency, the corresponding lighting effect is also changed. This avoids the problem of analyzing a music source that doesn’t necessarily change with the final output volume.

A SparkFun Spectrum Shield is used for frequency separation. An Arduino handles signal analysis, which sends a change effect command to the lighting controller when needed. There’s also a wireless remote available to adjust the lighting manually. 

This system was designed with the goal of having color-chasing LED effects that automatically sync with a hard music line. The color-chasing effects observed in the video are actually not synchronized to the music, but the changing of effects is. The system works well across many genres of music. This system is unique in that music volume does not matter. Many commercial implementations control lighting effects based off of overall volume intensity. This is problematic, as many people do not control final music volume with the source of the music (i.e. leaving your PC volume constant and controlling speaker volume instead.

An additional feature of this system is that it contains a wireless remote and the ability to control the lights independent of the music. This allows for rapid light patterns at parties, and soothing ambient lighting at all other times.

Code for the project is available in Shulman’s write-up, and the results can be seen in the demo video below. 

What do you do when you need to attach 400-500 screws for an upcoming project? If you’re “Progress Thailand” you simply create one yourself using a 9g micro servo modded for continuous rotation, an Arduino Nano, and some 3D printing!

The build uses a small thumb joystick for proportional control, and can accommodate a small hand driver in addition to a bit by itself. Impressively, a functional prototype of the tool was produced in a single day, with the final(?) version appearing a couple of days later. 

Hand and power tools are cheap, reliable, and easily accessible. But their production is still done in large centralized factories. 3D printing technology and cheap, open source electronics continue to improve bringing the decentralization of manufacturing one step closer.

We are experimenting with different designs to see how close current 3D printing technology can bring us to production-quality tools you can buy in the store. We’re also experimenting to see what modifications we can make to store-bought tools to enhance and customize their use.

While they note that the project isn’t meant to replace commercial screwdrivers at this point, it looks like a fun project with all the needed files available here to modify and improve things to your specifications!

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.

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.

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.