Posts with «featured» label

Build an Arduino Mega fingerprint door lock

If you don’t want to carry keycard or memorize a passcode, this build from Electronoobs might be just the thing. 

The system uses a fingerprint reader to check to see if you have access, and if approved, the device’s Arduino Mega unlocks the theoretical door using a micro servo motor. Three push buttons and a 16×2 LCD screen complete the user interface, and allow more authorized fingers to be added with the main person/finger’s permission.

While you might question the security gained by a hobby servo, the video notes that this could trigger any sort of security device, perhaps via a relay or electromagnetic coil lock. Besides security, the build gives a good introduction to Arduino fingerprint scanning, as well as the use of an SD card for data logging functions.

The Airdrum plays music with Arduino and six sensor PCBs

Playing music well can be difficult for anyone, especially those with certain disabilities. To make this form of self-expression easier for everyone,  Alessandro Verdiesen and Luuk van Kuijk built the Airdrum—an IR sensor-based instrument that is played simply by the wave of a hand.

The Airdrum uses six individual sensor boards to detect when a hand is present. This input is then processed via an Arduino Uno and passed along to a Raspberry Pi to produce individual tones.

People with multiple severe disabilities often encounter the difficulties of playing a music instrument due to their mental and physical deficits.

Health care institutions which facilitate housing, learning opportunities and day care for these people often encounter the difficulties of communicating with their clients. These institutions experienced that making music together is a great way of communicating and therefore many institutions offer music therapy. According to music therapists, the main goal is having fun. It is proven that people learn more when having fun. When playing an instrument, clients can share emotions and practice their motor skills.

We have designed a musical instrument which is easy and fun to play, not just for people with severe disabilities, but for everyone: the Airdrum. The Airdrum is a small device containing panels with motion sensors and colored lights. When somebody moves their hand or head above the panels, they light up and they play sound.

The device, as shown in the demo video, appears to still be a work-in-progress, but has all the functionality needed to play a simple tune with RGB LED feedback.

Hack your coffee machine with voice control

Are you still pushing buttons and adjusting knobs with your fingers to brew your favorite coffee? If so, then this voice-controlled solution could be the next project on your list.

To accomplish this hack, a rather high-end coffee maker was disassembled and modified, adding an Arduino Nano to press buttons, along with a small motor and driver board to adjust its dial. Voice control is provided via Snips software running on a Raspberry Pi, which passes the pertinent commands along for coffee making.

When the devices around you no longer require a lengthy operation manual, but rather, require only a voice command, this unlocks an environment where technology disappears into the background, so that you can regain the freedom to spend quality time with the people you care about. That is in fact our mission at Snips, to make technology disappear.

Case-in-point: this voice-activated coffee machine. You can ask it to make you a double espresso or a flat white, to pour you some hot water or even to turn itself off.

It’s purely a demo project, but at our Snips office in Paris, we’ve grown used to the convenience, and so we wanted to make it as easy as possible for anyone interested to replicate it at home.

Code and modification instructions are available on the Snips team’s blog post, while the brewing results can be seen in the demo video below. 

Show tidal shifts with this Arduino-powered moon clock

If you want to know the tide in your area, you could look it up in the paper, on the Internet, or using an app, but this moon-shaped tide clock provides a unique way to see what’s going on at a glance.

The 3D-printed device uses an Arduino Nano for processing, along with an RTC module to keep accurate time—thus accurate tide predictions. A tiny OLED display provides three info screens, selected via a rocket shaped button taking off of the moon’s surface. 

As the clock is meant for education, the moon design will provide a nice reminder of what actually shifts the tides. Arduino code as well as 3D-print files are available on the project’s write-up.

Arduino Blog 12 Sep 17:42

Sip and puff Morse code entry with Arduino

Those that need a text entry method other than a traditional keyboard and mouse often use a method where a character is selected, then input using a sip or puff of air from the user’s mouth. Naturally this is less than ideal, and one alternative interface shown here is to instead use sip/puff air currents to indicate the dots and dashes of Morse code.

The system—which can be seen in action in the video below—uses a modified film container, along with a pair of infrared emitters and detectors to sense air movement. The device was prototyped on an Arduino Mega, and its creators hope to eventually use a Leonardo for direct computer input. 

A tube connected to a custom made bipolar pressure switch drives an Arduino which translates puffing and sucking into Morse code and then into text.

Puffs make repeating short pulses (dots) and sucks repeating longer pulses (dashes) just like ham radio amateurs do with a dual-lever paddle.

Code for this open source project can be found on GitHub.

A beautifully-designed LEGO pneumatic compressor

LEGO sets have long been able to work with simple pneumatic controls, but what about a full air compressor built out of these components? Would this be possible?

As demonstrated in the video below, this can in fact be accomplished, and in brilliant style no less. The design uses four motors, eight pneumatic pumps, and 10 air tanks to produce a pressure of 35PSI and beyond.

Controls consist of an Arduino board, along with a pair of resistors to set two separate tank pressures. User feedback is provided by two external displays, and the setup even features a lighting system to allow “workers” to perform maintenance access 24 hours a day!

For a quick start, the compressor has a Turbo function which is enabled under 35 psi this makes the motors run on 12V instead of the rated 9V. This way the air tanks are filled a bit faster but without overloading the motors.

The compressor has two sections which can be used separately with their own setpoint or as one big compressor. This selection is done by switching the outlet valves at the back of the compressor and by setting a jumper on the circuit board.

The Arduino control also tracks the running time of each section in hours and is shown when a switch on the circuit board is pressed.

The pressure is measured by a non official Lego pneumatic sensor by Mindsensors.com.

Two-way lamp reborn with LEDs and Arduino

After finding a broken lamp at a scrapyard, which as meant to throw light both up and down, “tuenhidiy” decided to fix it. However, instead of using the normal two-bulb configuration, he replaced these lights with 64 individual RGB LEDs. The results are beautiful, as seen in the videos below.

Interestingly, this maker didn’t use NeoPixel-style programmable RGB lighting, but rather opted to control each RGB component directly using an Arduino, along with a shift register and transistor assembly. LED soldering was accomplished with the help of a flat wooden jig. The attached LEDs were then rolled up to fit the cylindrical fixture.

Lighting can be controlled in three modes—color wheel, morph, and HSB to RGB—with a potentiometer, selectable via a 3-way switch.

Build your own Arduino-powered portable function generator

If you need a certain electrical signal for testing, there are a variety of function generators available at a wide range of prices and capabilities. If, however, you’d like to build your own, this project by maker “Faransky” looks like a great place to start.

An Arduino Nano forms the core of this device, which interfaces with an AD9833 waveform generator module to produce the proper wave output. User interface is via a single encoder, which steps through different menu options using a built-in pushbutton, and a two-line LCD display provides feedback.

Everything is housed inside a nice compact enclosure, along with a lithium-ion battery to make it portable. Its capabilities are shown off in the video below, and build instructions and code are available here. 

Shy robotic sculpture imitates nature

In nature, animals often are sensitive to the outside environment, retreating into a hole, shell, or other protective structure upon sensing sudden movements. If you were to envision this kind of behavior in robot form, you might come up with something like “The Shy Machine” from Daric Gill Studios.

When it detects motion via a PIR sensor, the shell-like robot takes a reading of the ambient sound level using an internal microphone. If things are sufficiently quiet, it opens up using a stepper motor and lead screw, revealing a rainbow of colors provided by an array of RGB LEDs inside.

Its construction and a demo video are shown below, and you can see more about how this Arduino-powered robot was built and the results on Gill’s website.

Wheatley from Portal 2 comes to life with Arduino

If you’re a fan of Portal games, you’d probably like nothing more than to have your own Wheatley Personality Core to accompany you on real-life adventures. While that would be a passing thought for most, Luke Albertson has created his own amazing replica of the Portal 2 character. 

The device not only can say over 40 phrases from the game via an Adafruit soundboard, but contains a glowing blue eyeball that can pan, tilt, twist, and blink to help express what it’s thinking. It even has handles that move up and down, adding a kind of “flailing arms” effect to convey its emotions. 

Albertson’s animatronic project is controlled by an Arduino Uno, along with a Bluetooth shield and PS3 controller for user interface. It’s shown off quite nicely in the video below, and more info and clips are available here.