Posts with «featured» label

Connect Pour!

What do you get when you combine Connect Four with beer pong? Connect Pour, of course! After inspiration from a much larger basketball version, this hacker decided to make a device that allows you to throw ping pong balls into Solo cup targets. When one is hit, a vertical board stacks a light to represent a stacked checker above the cup in question.

An Arduino Uno powers the device, and lighting is provided by an RGB LED strip. Scores are tracked using an IR break beam sensor, and a button or RF remote can alternate player turns if you don’t hit anything.

I wrote the code of the game myself  and works basically as follows:

— the Arduino checks infrared beam break sensors under the plastic cups and a “pass button”

— if the state of the sensors/button changes from no beams being broken or buttons being pushed to a beam being broke or  a button being pushed

— the Arduino updates the game state updates the LEDs including the bar in the front (which indicates which player’s turn it is)

— repeat

The game looks like a lot of fun, though you may need some extra cups, as those on the machine no longer have bottoms! You can find more details on the build here.

A DIY hardware watchdog for your mining rig

Vadim Panov wanted a way to automatically restart a PC that was simple and cheap to make.

For this task, he turned to an Uno due to its wide availability; however, any Arduino board with at least one digital I/O pin and a USB-enabled serial port will work.

The device sends a “hello” string to the PC, to which it expects a “HELLO” back from the PC—running its own corresponding Java program—within 10 seconds. If it doesn’t receive this string, it assumes that the computer is frozen, and uses a reed relay to trigger the motherboard reset pin.

Panov’s idea could be used to monitor and reset cryptocurrency rigs, but could be adapted to other PC setups as needed.

Here’s how it works: the PC-side program tries to connect to every single serial port in your system within a period of 30 seconds (including the ports that appear during this process). To each port it’ll send the handshake string “hello” and monitor the input, expecting to receive uppercase “HELLO” back. When the handshake is finished, it’ll send ping strings once each five seconds.

The watchdog program on Arduino scans the input for “ping” strings. If no such string has been received within 10 second period, the watchdog will forcibly restart your PC.

Therefore, this scenario where you manually run it will be “one-off”, i.e. once the PC has been restarted, the watchdog will be stuck in the pre-handshake state. To make it work all the time, add the Java program to the startup list of your operating system of choice.

You can read more here and check it out in action below!

Test your aim in this carnival-style IR target game

For a class assignment, Matt Robb along with teammates Kara and Andrew needed to make a project using an Arduino and various other components. What they came up with was a carnival-style game that uses a stepper motor to rotate three targets containing IR sensors out of a nicely-painted cardboard box.

An Arduino Uno provides control for the game. When hit with a signal from an IR remote, an LED on the target goes out, a buzzer beeps, and it momentarily stops spinning.

It looks like it was a lot of fun to build and play, so be sure to check it out in the video seen here!

Measure RPM with an IR sensor and Arduino

When dealing with robotics and other electronics projects, it can be important to know how many revolutions a motor is making. From here, you can infer the distance that your device has traveled, or any number of other important variables.

If you’d like to get started with this type of sensing, this electronoobs tutorial will show you how to get things hooked up using an Arduino and a computer, along with an oscilloscope to verify measurements up to 10,000 RPM.

In his setup, an IR emitter/receiver bounces light off a spinning object. When light reflects back, it opens the circuit, causing the output to be grounded via a pulldown resistor, telling you that a revolution has been made. The 3D-printed device also features an OLED screen.

To emit infrared light we need a IR LED and to detect it a IR sensible transistor. Usually you could find those as a one unique module. To amplify the signal I’ve used the LM324 amplifier. You will also need a 100 ohm resistor and a 4.7k ohm one. To supply the system we will need a basic 9V battery and connector, an Arduino Nano, and an OLED screen. The case is 3D printed…

You can find more details on the build process here, as well as a demo of the tachometer below!

Arduino Blog 27 Feb 20:09

Make your own 3D-printed robotic vacuum with Arduino

Tired of cleaning your house? A robotic vacuum may be the logical solution, but if you’re “theking3737” something off-the-shelf just isn’t quite cool enough. Created as part of a school project, he was responsible for the hardware design, while a fellow classmate took care of the programming.

The DIY device uses an array of what appear to be ultrasonic sensors for navigation, and an Arduino Mega as the brains. It also features an HC-05 Bluetooth module that enables it to be controlled via an Android phone or smartwatch. All the electronics are housed inside a 3D-printed closure.

Impressively, the team had “never done anything like this before,” and the results look great—encouragement for anyone hesitant to start on a project because of inexperience!

Let an Arduino notify you when the coffee is ready

Hacker “wesgood,” apparently not satisfied with randomly checking the office coffee pot to see if a fresh brew was available, decided to make his own notification system.

His device uses a current sensor to monitor power usage of the coffee pot, and after some observation, he was able to pick out its brewing pattern—7A at 10 minutes, then quick cycling to keep the pot warm.

The system features an Arduino Yún for brew tracking and sends an alert via his office communication tool to let everyone know that a fresh pot is ready. As with many projects, the first iteration started life on a breadboard, but now exists on a manufactured PCB as a shield. It even has a second channel that is slated for use with the office kettle.

Once the Arduino side of the Yún detects the brew cycle is complete, it triggers a shell script under Linux that sends a notification to our office communication tool Hipchat. It also records the data about date and cycle stage so that Hipchat can query the database (on a webserver) and request things like what stage the brew cycle is on and when it brewed last.

You can find additional build details on Imgur.

Strange vocal interactions with ‘you, me and all these machines’

Moscow-based artist ::vtol:: is back again with an interesting interactive exhibit entitled “you, me and all these machines.” His latest work, a collaboration with Lovozero, allows two participants to produce otherworldly vocals together.

One participant wears the device, which points a directional microphone under the control of the other participant at her mouth using a servo motor. An array of LEDs signal the vocalist in a manner agreed upon before the performance.

The head-mounted system is controlled by an Arduino Uno, and is meant to display the subtle interaction between two participating artists, as they must work together to produce the desired output.

“You, me and all these machines” is a performance for voice and electronic devices. The vocalist puts on his or her head a specially designed wearable interface tool to interact with the voice and display a visual score. Technically, the device consists of several elements: a narrowly directional microphone driven by a motor; an LED strip that shows the vocalist score; remote control with a joystick used by the second participant to control the interface.

Shifting the microphone against the mouth makes it possible to achieve interesting sound effects, and makes it easier to manipulate the vocalist’s voice. The LED line consisting of 10 diodes is a very primitive, but effective and convenient way of interacting with the vocalist, and the way of interpreting the values is predetermined before each performance. During the performance, a sound canvas is formed, thereby changing the dynamics, consisting of a set of looped fragments created within voice and interface processing elements, without using other methods to generate sounds.

Check out “you, me and all these machines” in the video below!

Designing an Arduino-powered split-flap display

If you’d like a split-flap display with numbers and letters, options tend to be quite expensive. This though was no problem for hacker “scottbez1” who reports that after “only” two-plus years of work, he has produced a split-flap assembly that plugs into an Arduino Uno as a sort of external shield.

The device employs inexpensive stepper motors to click through letters, numbers, and even some punctuation, using cutout PVC ID display stock to show the characters. Cleverly, the PCB he designed for it can function as a motor driver or be split in two to function as a sensor board.

I’ve always loved these electro-mechanical displays, but you can’t buy them for a reasonable price, so I figured I’d try making them myself (plus it’s more fun that way!). Ultimately I wanted to design a split-flap display that can be built at home in small/single quantities and can be customized and put together by an intermediate hobbyist for not too much money.

The design I settled on uses PVC ID badge cards for the flaps, store-bought vinyl stickers for the letters, and is driven by a cheap 28BYJ-48 stepper motor. The enclosure and moving parts are all made from laser-cut MDF, which can be easily ordered online. To control them, I designed a driver board that can be hand-soldered and plugs into an Arduino like a shield.

The entire build story can be found here and more details including Arduino code are available on GitHub. If you’d just like to see and hear it flapping away, check out the video below!

Lunar landing conspiracy put to rest(?) with LIDAR

On July 20th, 1969 man first set foot on the moon with the Apollo 11 mission, or so they say. If it was faked, or so the theory goes, one would think that there were a few details that don’t quite add up. One such theory is that the hatch on the lunar module isn’t actually large enough to allow a fully-suited up astronaut to enter and exit the module.

Rather than make assumptions, astrophotographer and hacker “AstronomyLive” took matters into his own hands and used a homemade LIDAR unit to measure the hatch of Lunar Module #9 at the Kennedy Space Center, as well as an Apollo spacesuit.

The Arduino-powered device aims the laser, and transmits this information to a tablet that also provides a convenient user interface. This data was then arranged as a point cloud, proving that… You can take a guess, or watch the video below to see his conclusion!

I used the Garmin LIDAR-Lite V3 along with a couple of metal geared servo motors to build a simple pan/tilt scanner, which pairs via Bluetooth to an Android app I built using MIT App Inventor 2 to control and receive data from the Arduino. It’s simple but effective. Although every tutorial I read suggested I couldn’t safely pull the voltage off the board for the motors, but I found that the vin pin gave me no problems, as long as I used a 5V 1.5A linear voltage regulator between the pin and the motors. I supplied 9V using AA batteries to the power jack on the Arduino. In the future I may upgrade the scanner by adding a small camera to grab RGB data for each point as it samples, and ideally I would change the whole thing to use a stepper motor for continuous spinning and scanning to generate a denser cloud.

Levitate water drops with RGB LEDs and Arduino

Water normally falls from the sky to the ground, the time fountain from hacker isaac879 appears to work much differently. As shown in the video below, water droplets somehow levitate from a circular orange apparatus to a blue one on top.

The trick here is that the water isn’t actually falling up, but appears that way by carefully controlling the flashing of RGB lights using an Arduino Uno. If the lights flash at the same rate as the water drops, they appear to stand still, while if the light is flashed more slowly, they appear to rise.

This is the prototype RGB LED Time Fountain I designed and built. It uses RGB LED strip lights to strobe a stream of water drops to make them appear as if they are levitating. By strobing the different colors out of phase with each other some incredible effects can be created.

An Arduino Uno controls the timing of the RGB strobe and the PWM of the pump. Bluetooth communication was achieved using an HC-05 Bluetooth module and the “Arduino bluetooth controller” app by “Giumig Apps.”

Be sure to check out the video to see it in action, especially the bit around 3:40 where drops appear to rise out of a cup while it’s getting filled with water.