Posts with «arduino hacks» label

Stop Motion with the Time Glove

What do you get when you put an ultra-bright LED in the palm of a glove, and strobe it controlled by an accelerometer? A Time Control Glove! In creator [MadGyver]’s own words, it’s “just a stroboscope with frequency adjustment” but the effect is where all the fun is.

The Time Control Glove uses the stroboscopic effect, which many of us have seen used in timeless water drop fountains where the strobe rate makes drops appear to change speed, freeze in place, and even change direction. [MadGyver] made the entire assembly portable by putting it into a glove. An on-board accelerometer toggles the strobe in response to a shake, and the frequency is changed by twisting the glove left or right. The immediate visual feedback to the physical motions is great. The whole effect is really striking on the video, which is embedded below.

Schematics and bill of materials are available on GitHub. Brilliant work! And while we’re discussing the stroboscopic effect, find out how it can be used to tune guitar strings.

[via Arduino Blog]


Filed under: Arduino Hacks, how-to, led hacks

Listening for Hand Gestures

[B. Aswinth Raj] wanted to control a VLC player with hand gestures. He turned to two common ultrasonic sensors and Python to do the job. There is also, of course, an Arduino. You can see a video of the results, below.

The Arduino code reads the distance from both sensors — one for the left hand and the other for the right. This allows the device to react to single hand gestures that get closer or further away from one sensor as well as gestures involving both hands. For example, raising your left hand and moving it closer or further away will adjust the volume. The right hand controls rewind and fast forward. Raising both hands will start or stop playback.

Of course, since the Arduino is reading the gestures you could change them to suit you. We might have mounted the sensors further back (or, perhaps, added more sensors) so you could use trigonometry to triangulate the hand’s exact position. Well, perhaps not exact, but you could get an idea of the hand’s motion from right to left as well as forward and backward.

On the host computer side, Python receives serial data from the Arduino and then simulates keystrokes to get the desired result. Of course, this is also highly customizable.

By coincidence, we did a similar project a few years ago using one sensor and the Arduino’s ability to appear like a USB keyboard. We’ve also seen 8 sensors making piano music.


Filed under: Arduino Hacks
Hack a Day 02 Nov 03:00

Add Intuitiveness to OpenSCAD With Encoders

The first time I saw 3D modeling and 3D printing used practically was at a hack day event. We printed simple plastic struts to hold a couple of spring-loaded wires apart. Nothing revolutionary as far as parts go but it was the moment I realized the value of a printer.

Since then, I have used OpenSCAD because that is what I saw the first time but the intuitiveness of other programs led me to develop the OpenVectorKB which allowed the ubiquitous vectors in OpenSCAD to be changed at will while keeping the parametric qualities of the program, and even leveraging them.

All three values in a vector, X, Y, and Z, are modified by twisting encoder knobs. The device acts as a keyboard to

  1. select the relevant value
  2. replace it with an updated value
  3. refresh the display
  4. move the cursor back to the starting point

There is no software to install and it runs off a Teensy-LC so reprogramming it for other programs is possible in any program where rotary encoders may be useful. Additional modes include a mouse, arrow keys, Audacity editing controls, and VLC time searching.

Here’s an article in favor of OpenSCAD and here’s one against it. This article does a good job of explaining OpenSCAD.

[Editor’s note: This is a Hackaday writer’s hack, hence the “I” in place of the usual “we”. We all love custom peripherals though, and a good number of us love OpenSCAD, so you could probably read it either way, but we don’t want to take credit for [Brian]’s work.]


Filed under: 3d Printer hacks, Arduino Hacks

Tiny, Wearable 8-Bit VT100 Terminal

In the modern era of computing, the end-user is often quite far removed from the machine they’re using. At least in terms of abstraction levels, the user experience of most computers, smart phones, and the like are very far away from the zeros and ones. If you need to get down to that level though, you’ll have to make your way to a terminal somehow, and reminisce fondly about the days when everything was accessed through a serial line.

Nowadays, some harmless nostalgia is often accompanied by a challenge as well, as [Nick] demonstrated with his tiny serial terminal. It mimics the parsing and rendering of a VT100 console using an Arduino Uno and a 1″x1″ TFT screen. His goal was to make it wearable like a wristwatch would be, using two buttons as an HID device. With the size and simple interface, [Nick] also explores the possibility of mounting such a terminal to a pair of glasses.

While not everyone may want to interact with a serial terminal with only two buttons, it’s certainly a great demonstration of what is possible when it comes to implementing retro software in unique ways. There have been serial terminals implemented in many other unique places as well, such as old oscilloscopes and replicas from popular video games.


Filed under: Arduino Hacks

Look what came out of my USB charger !

Quick Charge, Qualcomm’s power delivery over USB technology, was introduced in 2013 and has evolved over several versions offering increasing levels of power transfer. The current version — QCv3.0 — offers 18 W power at voltage levels between 3.6 V to 20 V.  Moreover, connected devices can negotiate and request any voltage between these two limits in 200 mV steps. After some tinkering, [Vincent Deconinck] succeeded in turning a Quick Charge 3.0 charger into a variable voltage power supply.

His blog post is a great introduction and walk through of the Quick Charge ecosystem. [Vincent] was motivated after reading about [Septillion] and [Hugatry]’s work on coaxing a QCv2.0 charger into a variable voltage source which could output either 5 V, 9 V or 12 V. He built upon their work and added QCv3.0 features to create a new QC3Control library.

To come to grips with what happens under the hood, he first obtained several QC2 and QC3 chargers, hooked them up to an Arduino, and ran the QC2Control library to see how they respond. There were some unexpected results; every time a 5 V handshake request was exchanged during QC mode, the chargers reset, their outputs dropped to 0 V and then settled back to a fixed 5 V output. After that, a fresh handshake was needed to revert to QC mode. Digging deeper, he learned that the Quick Charge system relies on specific control voltages being detected on the D+ and D- terminals of the USB port to determine mode and output voltage. These control voltages are generated using resistor networks connected to the microcontroller GPIO pins. After building a fresh resistor network designed to more closely produce the recommended control voltages, and then optimizing it further to use just two micro-controller pins, he was able to get it to work as expected. Armed with all of this information, he then proceeded to design the QC3Control library, available for download on GitHub.

Thanks to his new library and a dual output QC3 charger, he was able to generate the Jolly Wrencher on his Rigol, by getting the Arduino to quickly make voltage change requests.


Filed under: Arduino Hacks, hardware

Hassle-Free Classical Conditioning for Honey Bees

When you’re sick or have a headache, you tend to see things a bit differently. An ill-feeling human will display a cognitive bias and expect the world to punish them further. The same is true of honey bees. They are intelligent creatures that exhibit a variety of life skills, such as decision-making and learning.

It was proven back in 2011 that honey bees will make more pessimistic decisions after being shaken in a way that simulates an attack by varroa destructor mites. The bees were trained to associate a reward of sugar-water with a particular odor and to associate foul-tasting punishment water with another odor—that of formic acid, a common treatment against varroa mites. When a third stimulus created by mixing the two odors was presented, the experimenters found that the aggravated bees were more likely to expect the bad odor. Sure enough, they kept their tongues in their mouths when they smelled the third odor. All the bees that weren’t shaken looked forward to sucking down a bit of sugar-water.

So, how does one judge a honey bee’s response? Whenever their antennae come in contact with something appetizing, they stick out their proboscis involuntarily to have a taste. This is called proboscis extension reflex (PER), and it’s the ingrained, day-one behavior that leads them to suck the nectar out of flower blossoms and regurgitate it to make honey.

[LJohann] is a behavioral biologist who wanted to test the effects of varroa mite treatment on bee-havior by itself, without agitating the bees. He built a testing apparatus to pump odors toward bees and judge their response which is shown in a few brief demo videos after the break. This device enables [LJohann] to restrain a bee, tantalize its antennae with sucrose, and pump a stimulus odor at its face on the cue of an LED and piezo buzzer. A fan mounted behind the bee helps clear the air of the previous scents. We especially like the use of a servo to swing the tube in and out of the bee’s face between tests.

[LJohann] and his colleagues concluded that the varroa mite treatment by itself does not make the bees pessimistic. This is great news for concerned apiarists who might be skeptical about using formic acid in the fight against the honey bee’s worst predator. Check out the brief demo videos after the break.

Hackaday has long been abuzz about bees whether they produce honey or not. We’ve covered many kinds of sweet projects like intelligent hives, remote hive weight monitoring, and man-made bee nest alternatives.


Filed under: Arduino Hacks

Click Your Heels Thrice, Hail a Cab Home

If Dorothy from The Wizard of Oz were to wake up in 2017, with her magic Ruby Slippers on her feet, she’d probably believe she had woken up in a magical world. But modern folks will need a little more magic to impress them. Like Clicking your heels thrice to get home with these Uber ruby slippers. [Hannah Joshua] was tasked by her employer to build a quirky maker project. She got an idea when a friend complained about having trouble hailing a cab at the end of a hard day at work.

[Hannah] started with ruby colored slippers with a platform toe and high heels to allow space to stuff in all the magic dust, err, electronic bits. The initial plan was to use an Arduino with a GSM/GPS shield but that would have needed a separate SIM card and data plan for the shoes. Instead, she opted for the 1Sheeld which connects to a smart phone over Bluetooth. The 1Sheeld gets access to all of the smart phone’s sensors including the GPS as well as the data connection. The Arduino and 1Sheeld are put in a cavity carved out in the toe section. The 9 V battery goes inside another cavity in the heel, where an activation switch is also installed. Three LED’s indicate when the shoe is active, the cab request is accepted, and when the cab is on its way.

The code is basic since this one of her first Arduino projects, but it gets the job done. It sends an http request to Uber’s API to request a cab. The destination is hard-coded, so the slippers only allow you to get from your current location to whatever destination is programmed. The GitHub repository provides code, as well as some additional information on construction. [Hannah] has also added notes explaining some of the design choices and things to take care about if you plan to build one of these magic slippers.

We covered the 1Sheeld when it was introduced several years back, and if you get your hands on one, try building this Hand Waving Door Unlocker.

 


Filed under: Arduino Hacks

Nematoduino: A Roundworm Neural Model on an Arduino

When it comes to building a neural network to simulate complex behavior, Arduino isn’t exactly the first platform that springs to mind. But when your goal is to model the behavior of an organism with only a handful of neurons, the constraints presented by an Arduino start to make sense.

It may be the most important non-segmented worm you’ve never heard of, but Caenorhabditis elegans, mercifully abbreviated C. elegans, is an important model organism for neurobiology, having had its entire nervous system mapped in 2012. [Nathan Griffith] used this “connectome” to simulate a subset of the diminutive nematode’s behaviors, specifically movements toward attractants and away from obstacles. Riding atop a small robot chassis, the Arduino sends signals to the motors when the model determines it’s time to fire the virtual worm’s muscles. An ultrasonic sensor stands in for the “nose touch” neurons of the real worm, and when the model is not busy avoiding a touch, it’s actively seeking something to eat using the “chemotaxis” behavior. The model is up on GitHub and [Nathan] hopes it provides an approachable platform for would-be neuroroboticists.

This isn’t the first time someone has modeled the nematode’s connectome in silico, but kudos to [Nathan] for accomplishing it within the constraints an Arduino presents.


Filed under: Arduino Hacks, misc hacks

Arduino Uno Strain Relief

Do jumper wires pulling out of your Uno have you pulling your hair out? Is troubleshooting loose jumpers making you lose your mind?  Are your projects backing up because of all the time you’ve lost keeping jumper wires secure in your Arduino Uno? Then you need the all new Ardunio Strain Relief Enclosure!

[Jeremy Cook] has had it with loose jumpers pulling out of his Uno, so he designed a case that not only secures the Arduino; it also keeps those dastardly jumper wires from pulling out at the most inconvenient times.

Composed of 3/4 inch thick MDF and 1/8 inch thick polycarbonate, the Arduino Strain Relief enclosure is sure to be a hit for every hacker’s work bench. [Jeremy] used a CNC router to cut the enclosure and top. The plastic top is secured to the MDF base via four 4-40 screws. Interestingly – he applied super glue to the screw holes in the MDF before tapping them. We’ll have to try this trick on our next project!


Filed under: Arduino Hacks

“The Cow Jumped Over The Moon”

[Ash] built Moo-Bot, a robot cow scarecrow to enter the competition at a local scarecrow festival. We’re not sure if Moo-bot will win the competition, but it sure is a winning hack for us. [Ash]’s blog is peppered with delightful prose and tons of pictures, making this an easy to build project for anyone with access to basic carpentry and electronics tools. One of the festival’s theme was “Out of this World” for space and sci-fi scarecrows. When [Ash] heard his 3-year old son sing “hey diddle diddle, the cat and the fiddle…”, he immediately thought of building a cow jumping over the moon scarecrow. And since he had not seen any interactive scarecrows at earlier festivals, he decided to give his jumping cow a lively character.

Construction of the Moo-Bot is broken up in to three parts. The skeleton is built from lumber slabs and planks. The insides are then gutted with all of the electronics. Finally, the whole cow is skinned using sheet metal and finished off with greebles to add detailing such as ears, legs, spots and nostrils. And since it is installed in the open, its skin also doubles up to help Moo-bot stay dry on the insides when it rains. To make Moo-Bot easy to transport from barn to launchpad, it’s broken up in to three modules — the body, the head and the mounting post with the moon.

Moo-Bot has an Arduino brain which wakes up when the push button on its mouth is pressed. Its two OLED screen eyes open up, and the MP3 player sends bovine sounding audio clips to a large sound box. The Arduino also triggers some lights around the Moon. Juice for running the whole show comes from a bank of eight, large type “D” cells wired to provide 6 V — enough to keep Moo-Bot fed for at least a couple of months.

Check out the video after the break to hear Moo-bot tell some cow jokes – it’s pretty funny. We’re rooting for it to win the competition — Go Moo-bot.

If you’re hungry for more scarecrows, this isn’t the first we’ve seen.


Filed under: Arduino Hacks, robots hacks