Posts with «arduino» label

Custom “doorbell” flashes house lights for the hearing impaired

Darren Lewis’ parents both have a difficult time hearing the doorbell. He experimented with an off-the-shelf flashing light, but found that could only really be seen when they were in the room—an obvious problem. In response to this, Lewis decided to make his own system that flashes multiple house lights at the same time.

His device uses an Arduino Nano to detect the stock doorbell speaker voltage. When a press is sensed, it then activates a RF light switch via a modified remote, using an output pin and opto-isolator to substitute in for the normal button press. 

It’s a clever hack, and certainly one that will certainly help alleviate doorbell frustration in the future!

Maker Faire NY: Developing for the Final Frontier

The cost of getting a piece of hardware into space is now cheaper than ever, thanks in no small part to the rapid progress that’s been made by commercial launch providers such as SpaceX. In the near future, as more low-cost providers come online, it should get even cheaper. Within a few years, we could be seeing per kilogram costs to low Earth orbit that are 1/10th what they were on the Space Shuttle. To be sure, this is a very exciting time to be in the business of designing and building spacecraft.

But no matter how cheap launches to orbit get, it’ll never be cheaper than simply emailing some source code up to the International Space Station (ISS). With that in mind, there are several programs which offer students the closest thing to booking passage on a Falcon 9: the chance to develop software that can be run aboard the Station. At the 2018 World Maker Faire in New York we got a chance to get up close and personal with functional replicas of the hardware that’s already on orbit, known in space parlance as “ground units”.

On display was a replica of one of the SPHERES free-flying satellites that have been on the ISS since 2006. They are roughly the size of a soccer ball and utilize CO2 thrusters and ultrasonic sensors to move around inside of the Station. Designed by MIT as a way to study spaceflight techniques such as docking and navigation without the expense and risk of using a full scale vehicle, the SPHERES satellites are perhaps the only operational spacecraft to have never been exposed to space itself.

MIT now runs the annual “Zero Robotics” competition, which tasks middle and high school students with solving a specific challenge using the SPHERES satellites. Competitors run their programs on simulators until the finals, which are conducted using the real hardware on the ISS and live-streamed to schools.

We also saw hardware from “Quest for Space”, which is a company offering curricula for elementary through high school students which include not only the ground units, but training and technical support when and if the school decides to send the code to the matching hardware on the Station. For an additional fee, they will even work with the school to design, launch, and recover a custom hardware experiment.

Their standard hardware is based on off-the-shelf platforms such as Arduino and LEGO Mindstorms EV3, which makes for an easy transition for school’s existing STEM programs. The current hardware in orbit is setup for experiments dealing with heat absorption, humidity, and convection, but “Quest for Space” notes they change out the hardware every two years to provide different experiment opportunities.

Projects such as these, along with previous efforts such as the ArduSat, offer a unique way for the masses to connect with space in ways which would have been unthinkable before the turn of the 21st century. It’s still up for debate if anyone reading Hackaday in 2018 will personally get a chance to slip Earth’s surly bonds, but at least you can rest easy knowing your software bugs can hitch a ride off the planet.

View the sea floor in 360° with this Arduino-powered dropcam

A dive mask or even SCUBA tanks are a great way to explore the ocean, but at depths of much more than 30 meters, things become a bit dicey. 1,000 meters is generally unthinkable for amateur divers but WorkshopScience has come up with a way to explore these regions without undue danger.

His device, developed during an internship with Blue Robotics, is touted as the world’s first consumer deep-sea dropcam. It’s able to dive to 1,000 meters and capture 360° video, as well as pressure and temperature readings. 

When a sufficient amount of time has passed, an Arduino board releases a weight by disintegrating a length of nichrome wire with electrical current. It then floats to the surface for data analysis. How it works, along with a resulting 360° video can be seen below.

Giant Connect Four Pits You Against the Computer

You can build a Connect Four solver in software, but it won’t be all that much fun. Now apply that same automation to a 15-foot-tall plywood version of the classic board game and you’ve just created a smile-making-machine for everyone within eyesight. Behold the Mono-Purpose Automated Robot Versed In Connnect4 (Marvin) which Ben and Jonathan dreamed up on their way home from Maker Faire last year, and made into their exhibit this year.

On the physical side of things they got really creative in lifting the discs and sorting them into the column chosen by the software brain of the game. A chain travels along one side with fingers every few feet. The fingers travel along the channel, lifting the discs. Those fingers are a couple of bolts, with some metal filler, all epoxied into one solid unit.

At the top of the disc elevator, and at the top position of each column in the gaming board, there are IR reflectance sensors which send feedback to the Arduino that drives the hardware. This proved a major issue during setup the day before the Faire. The reflectance sensors are just blasting out IR and not using a carrier signal. In direct sunlight, the detector was in a constant state of being tripped. After some trial and error, the logic for the sensors was flipped to detect the absence of sunlight by placing black plastic behind that top row of the board and putting duct tape over the IR emittors.

There’s a router and laptop rolled into the system. The Arduino makes an HTTP request to software on the laptop. In addition to determining where the next move should be made, the laptop is connected to a large screen which shows the current state of the gaming board. This is a head-to-head, human versus machine game. The human player drops their discs from the top of the board using a paint roller that hooks into a hole at the center of the disc. This way the player’s disc passes by the sensors, triggering the machine’s next move.

It’s a clever build and due to the sheer size it’s pretty awesome they were able to get it to the Faire from Philadelphia. Don’t miss the video after the break that shows off the fun and excitement of this gaming giant.

Three-axis rotary machining with Arduino

For many years CNC machining was the purview of well-equipped shops and manufacturing facilities. With the availability of inexpensive control hardware, such as Arduino-based GRBL packages, this type of control has come to the (technically inclined) masses, enabling us to create complicated 2D and 3D shapes automatically.

Normally, this means X, Y, and Z axes that control a cutting head, and if you wanted to much further in complexity and cost, you could add a fourth or even a fifth axis to tilt things as needed. The RotoMill, however, seen at World Maker Faire in New York, puts a different “spin” on things, substituting a stepper-controlled spindle for the Y axis. The result is a machine with unique machining capabilities, driven by an Arduino Uno running custom GRBL firmware.

As for now, the CNC can easily mill parts out of softer materials like plastic, wood, and foam, although it is designed to cut aluminum as well.

A three-axis rotary CNC built for the Mechanical Engineering senior design capstone course at Carnegie Mellon University by a team of engineering students. The CNC uses NEMA24 motors for each of the axes, with the X and Z axes actuated by lead screws, and the A (rotary) axis actuated by a worm gear. The spindle is an off-the-shelf Makita hand router, which allows for any router bit to be used.

Each motor is controlled by a stepper motor driver, which are all coordinated by an Arduino Uno running a customized version of the GRBL firmware. This is in turn controlled by a laptop running open-source GCode sending software.

To generate the GCode, we would create a 3D model of the part that we wanted to machine. We then “unwrapped” about the A axis. This basically takes the part and converts it from Cartesian coordinates to Cylindrical coordinates.

To generate the GCode, we would create a 3D model of the part that we wanted to machine. We then “unwrapped” about the A axis. This basically takes the part and converts it from Cartesian coordinates to Cylindrical coordinates.

At this point, we could take the unwrapped part and load it into Autodesk HSM, a popular industrial CAM package. This allowed us to generate a toolpath for machining the part. We basically “fooled” the CNC into thinking that it was a normal, three-axis Cartesian CNC. The trick, however, is that the Y axis is wrapped around and becomes the A axis.

Additional information and photos can be found on RotoMill’s page or Hackaday’s recent write-up.

DIY Puff-Suck Interface Aims for Faster Text Input

Puff and Suck (or Sip and Puff) systems allow people with little to no arm mobility to more easily interact with computers by using a straw-like unit as an input device. [Ana] tells us that the usual way these devices are used to input text involves a screen-based keyboard; a cursor is moved to a letter using some method (joystick, mouse emulator, buttons, or eye tracking) and that letter is selected with a sip or puff into a tube.

[Ana] saw such systems as effective and intuitive to use, but also limited in speed because there’s only so fast that one can select letters one at a time. That led to trying a new method; one that requires a bit more work on the user’s part, but the reward is faster text entry. The Puff-Suck Interface for Fast Text Input turns a hollow plastic disk and a rubber diaphragm into bipolar pressure switch, able to detect three states: suck, puff, and idle. The unit works by having an IR emitter and receiver pair on each side of a diaphragm (one half of which is shown in the image above). When air is blown into or sucked out of the unit, the diaphragm moves and physically blocks one or the other emitter-receiver pair. The resulting signals are interpreted by an attached Arduino.

How does this enable faster text input? By throwing out the usual “screen keyboard” interface and using Morse code, with puffs as dots and sucks as dashes. The project then acts as a kind of Morse code keyboard. It does require skill on the user’s part, but the reward is much faster text entry. The idea got selected as a finalist in the Human-Computer Interface Challenge portion of the 2018 Hackaday Prize!

Morse code may seem like a strange throwback to some, but not only does the bipolar nature of [Ana]’s puff-suck switch closely resemble that of Morse code input paddles, it’s also easy to learn. Morse code is far from dead; we have pages of projects and news showing its involvement in everything from whimsical projects to solving serious communication needs.

Calling volunteers for Maker Faire Rome!

Planning to attend Maker Faire Rome in October? We’re currently seeking volunteers to join our team during the event—staffing tables and displays, helping with demos, and providing technical assistance when necessary.

Those who help us for one shift will receive a day pass; spend two days with us, and you’ll have a ticket for the entire weekend to explore the show. Water and snacks will be provided, of course, and we’ve even prepared a small gift to show our appreciation for your time and effort.

Interested? Please fill out this questionnaire, and we’ll get back to you soon! (If you are under the age of 18, we will need your parents’ permission.)

Maker Faire Rome: AAA, cercasi volontarie e volontari per il booth Arduino

Cercasi volontari/e per Arduino! Hai in programma di visitare Maker Faire Roma? Siamo alla ricerca di volontarie e volontari per lo il nostro booth – che ci aiutino a spiegare i progetti e diano supporto durante le demo.

Con un turno di volontariato allo stand Arduino, avrai a disposizione un pass per la giornata; se, invece, sarai al nostro booth per almeno due giorni avrai il pass per l’intero evento. Sappiamo quanto sia importante il tuo tempo e quanto sia fondamentale il tuo aiuto al nostro booth, per questo motivo saremo felici di offrirti il pranzo e una selezione di gadget Arduino.

Ti interessa partecipare al booth Arduino? Per favore completa questo form, ti faremo sapere prestissimo!

Se hai meno di 18 anni, puoi partecipare ma con il consenso firmato dei tuoi genitori!

Cheating the Perfect Wheelie With Sensors And Servos

Everyone remembers popping their first wheelie on a bike. It’s an exhilarating moment when you figure out just the right mechanics to get balanced over the rear axle for a few glorious seconds of being the coolest kid on the block. Then gravity takes over, and you either learn how to dismount the bike over the rear wheel, or more likely end up looking at the sky wondering how you got on the ground.

Had only this wheelie cheating device been available way back when, many of us could have avoided that ignominious fate. [Tom Stanton]’s quest for the perfect wheelie led him to the design, which is actually pretty simple. The basic idea is to apply the brakes automatically when the bike reaches the critical angle beyond which one dares not go. The brakes slow the bike, the front wheel comes down, and the brakes release to allow you to continue pumping along with the wheelie. The angle is read by an accelerometer hooked to an Arduino, and the rear brake lever is pulled by a hobby servo. We honestly thought the servo would have nowhere near the torque needed, but in fact it did a fine job. As with most of [Tom]’s build his design process had a lot of fits and starts, but that’s all part of the learning. Was it worth it? We’ll let [Tom] discuss that in the video, but suffice it to say that he never hit the pavement in his field testing, although he appeared to be wheelie-proficient going into the project.

Still, it was an interesting build, and begs the question of how the system could be improved. Might there be some clues in this self-balancing motorized unicycle?

Star Wars mouse droid reveals hidden scrolling LED display

In several iterations of the Star Wars saga, small black droids can be seen scurrying around imperial installations. While they tend to fade into the background or provide a fun distraction in the movies, the mouse droid by Potent Printables acts as a sort of physical messaging app. It’s able to travel to the correct location, then pop open to unveil a scrolling LED sign.

Potent Printables can trigger the side door using a Bluetooth app on his phone. On command, an RC servo pushes it open, and lowers it down using a stepper motor/reel setup. An Arduino Uno along with an Adafruit Motor Shield are used for control, while an HC-05 module enables communication with the system.  

Check out the latest video in this build series below!

ArdOsc is a matchbox-sized, Arduino Nano-based oscilloscope

Oscilloscopes come in all different shapes and sizes, and now with just a few discreet components, maker Peter Balch has been able to turn an Arduino Nano into an oscilloscope the size of a matchbox. 

The simplest version of this device, which he calls the “ArdOsc,” displays data on a computer screen, but a small 1.3” OLED can also be added if you want to use it on its own.

His build write-up goes through several versions of the instrument, progressively adding capabilities including a logic display, signal generator, and other useful tools. It’s certainly worth checking out, whether you need tiny test equipment or just want to marvel at how something this small can be made!

This oscilloscope costs the price of an Arduino Nano, plus a few pence for resistors, etc. Its specifications are:

  • Max 1M samples/second, min 1000sps
  • 8-bits per sample
  • DC 0-5V; AC +/- 550mV, AC +/- 117mV, AC +/- 25mV
  • USB “PC scope” or built-in display
  • Could be battery-powered
  • Optional logic display
  • Optional frequency meter
  • Optional voltmeter