Tag Archives: Makers

Watch a robot solve a Rubik’s Cube in one second

This Arduino-driven robot will unfix a Rubik’s Cube before you could even finish reading this sentence.  

Last November, 14-year-old Lucas Etter set a new world record for the fastest time to solve a Rubik’s Cube, becoming the first person to ever break the five-second barrier for unravel the iconic 3 x 3 x 3 puzzle. As impressive as that may be, nothing may compare to this duo’s latest project. That’s because software engineers Jay Flatland and Paul Rose have devised an automated mechanism that can crack it in just over a second.


With an Atmel chip at its heart, the system is comprised of stepper motors, some 3D-printed parts and four webcams all connected to a Linux-based computer. The software engineers used the Kociemba algorithm to solve the puzzle, and have modified the Rubik’s Cube by drilling four holes into the middle of each of its six sides so the robot could manipulate it. Since the robot needs the cameras in order to function, the webcams are covered with a piece of paper until the cube is properly scrambled.

The team is now in the process of applying for the Guinness World Record. Pending all goes to plan, the robot will crush the current record holder’s time of 3.253 seconds.

This tennis racquet grunts like Sharapova (and others) when you swing it

A racquet that makes quite the racket.

Conventional wisdom says that tennis players grunt because it helps them apply the maximal force when they strike the ball. However, don’t be fooled, these noises are totally unnecessary and downright annoying. In fact, there are top names in the game like Maria Sharapova whose screams routinely top 100 decibels. This has led many, including the legendary Martina Navratilova, to call into question whether or not the behavior is actually a form of cheating.


Cognizant of this, Maker Seiya Kobayashi has come up with a hilarious solution for this problem: a racquet that does the grunting for you. You simply select one of four notable noisemakers — Serena Williams, Maria Sharapova, Novak Djokovic and Rafael Nadal — and the aptly named Grunting Racket will take care of the rest.


This allows you to focus on your footwork and hitting the ball, while the combination of an Arduino Pro Mini (ATmega328), an accelerometer and speaker emits the obnoxious sounds. Additional components include a LiPo battery, an Adafruit Audio FX Sound Board and a button on the grip that lets you choose the player. These electronics are all housed inside the racquet’s handle. Kobayashi employed both Arduino and Processing sketches along the way to prototype his idea.

How it works is fairly simple: When a value from the accelerometer exceeds a particular threshold, the sound board will play one of the four tones. You can see (and hear) it action below!

[s/o to fellow tennis players Artie Beavis and David Scheltema]

ATtiny85 helps breathe new life into a broken scale

Rather than toss out a broken bathroom scale, this father-son duo decided to refurbish it with an all-new electrical system.

What do you do when your scale breaks? If you’re like most people, you either buy a new one, or don’t weigh yourself hoping that you didn’t actually gain any weight over the holidays. If, however, you are Oxford doctoral student Ilias Giechaskiel, you simply design a new electrical system for it, then build it with the help of your dad.


As the Maker puts it, “The obvious solution…was to get rid of the internal components, reuse the case and the sensors, and build everything from scratch.”

One of the more interesting techniques employed in this project is the use of a Wheatstone bridge in conjunction with a load cell to measure weight. As the voltage change in this type of setup is quite small, a separate chip was needed to amplify the signal before it was passed to an ATtiny85’s analog input. Another neat design choice was the use of the ATtiny85 with its limited input/output (IO) capability (5 IO pins plus a reset pin).


Giechaskiel explains his selection of MCU,“I like its small form-factor, and did not want to have unused pins.” However, he does admit that more I/O would have been useful to implement more functionality in the scale.

If that wasn’t enough, he programmed the ATtiny with an Arduino, as outlined in these instructions, and his new display is a nice bright red. This would seem to be an improvement over the boring gray, though if you’re not happy with the reading, it might be harder to conceal!


There are several neat concepts in this build, so be sure to check out his code, library, and schematics on GitHub. if you think you might be able to use some of these ideas!



This five-axis robotic arm will lend you a helping hand

One Maker decided to build his own 5-DOF robotic arm using ServoCity parts, a Pololu Mini Maestro controller and an Arduino Uno. 

If you’re wondering when you’ll get the time to work on all of your crazy projects, you might look forward to retirement. This is great if you’re close, though possibly discouraging for younger workers. Either way, 62-year-old “CyberMerin” decided to make his own robotic arm from scratch. As he puts it, “I promised myself was that when I did retire I was going to complete all those projects I had running around inside my head … That’s about 50 years or so of projects.”


He also notes that microprocessors didn’t exist years ago, and a machine shop was needed to make mechanical parts. It’s a great time to be alive for those that love to build stuff!

This particular project, a five-axis robotic arm is quite ambitious, works well and is extremely well-documented, even including pictures of 3D CAD models. Though complicated, the Arduino wiring is relatively simple since it communicates serially with a Mini Maestro USB servo controller. This allows the Maestro to do the “heavy lifting” for each servo. (Be sure to check out his article for a huge amount of background on building something like this.)


Human interface is handled by a nice graphic slider setup running in Processing 3. As shown in the video below it responds quickly to commands. (Check out around 3:00 when it stacks a green block on the other two.)

For an entirely different take on a robotic arm, here’s one that employs only three servos, a coffee tin for a base, and a gaming controller. Even with these limitations, it still manages to be able to manipulate objects.

These string racing robots are awesome

One Maker decided to build tiny autonomous robots that could go back and forth along some string like a cable car. 

According to Adafruit forums user HarpDude, “Back in the 1980s, my college-aged brother designed a simple motor+battery car that raced along a string between the birch tree and the street-side power pole. For years now, we’ve been improving on the design.” Although this seems like a fun experiment by itself, one major weakness of the design was that it crashed at the end of its run, needing a human to catch it.


Now 30 or so years later, encouraged by his son the ‘Dude decided to get back into electronic design. Proving that no Maker project is never really finished, he decided to start making these racers again. This time though, his goal was to make them autonomous, able to avoid crashing at the end of the string.

HarpDude’s background is in transistor-based logic, but after discovering the Arduino for himself, it seemed like a this type of system would work well in his device. Adafruit’s Trinket, with an ATtiny85 at its core, fit the bill perfectly for his little device, and at around seven bucks, wouldn’t be a tragedy if one did end up crashing.


Currently, his string racer can be used in two modes, “Boomerang,” which travels to the end of the line and comes back, and “Pong,” which goes back and forth continuously. Besides racing, perhaps something like this used with a tiny camera to take neat video footage, or with a slower motor in time-lapse mode.

Maker builds a Pro Trinket-powered GPS watch

Hey, watch-a got there?! 

Sure, you could always go buy a GPS watch like the TomTom Spark or Garmin Forerunner. Or, you could be like Shawn Cruise and build your own nifty, somewhat Steampunkish wearable device.


The Arduino GPS Watch, which is made up of two leather cuffs, consists of a 128×32 OLED display, a 3V Pro Trinket (ATmega328) with a battery pack, and an Adafruit Ultimate GPS breakout board. There are two tactile buttons and an RGB LED on the outside, as well as a temperature sensor, three 220 Ohm resistors and a 4.7K Ohm resistor mounted to a perfboard. The wires and battery are all hidden between the two straps.


Admittedly, the watch came out a bit thicker and bulkier than Cruise had originally intended, but is pretty sweet nevertheless! It boasts a wide range of features, including the ability to show time, read temperature, reveal GPS coordinates, and even packs a flashlight that can illuminate a dark space.

Beyond that, wearers can use the device to find and mark a coordinate, and then return to it as they move around. The OLED screen shares direction and speed, too. You can watch the video below as Cruise takes you through some more of the watch’s other core elements.

This giant LED thermometer scarf shows the temp outside

With this scarf, you’ll never have to wonder how cold it is when you step outside.

Winter is well underway in some parts of the country, and if you have to head out into the frigid air, you’ll probably want a comfy scarf around your neck. But what about an accessory that not only keeps you warm, but looks and functions as a giant thermometer as well? That’s exactly what Instructables user “caitlinsdad” has created using an Adafruit FLORA (ATmega32U4), humidity and temperature sensor modules to detect the weather conditions, a NeoPixel ring for the bulb, and an LED strip to reveal the temp in both Fahrenheit and Celsius.