ArduinoMania

With the current coronavirus situation, we’ve been encouraged to wash our hands regularly for 20 seconds – or approximately how long it takes you to hum “Happy Birthday” from beginning to end twice. That sounds easy enough, but do you really do this every time? What you need is some sort of automatic timer, perhaps with a dial gauge for easy visual reference. 

As it just so happens, Gautam Bose and Lucas Ochoa built such a device with an Arduino Uno. The aptly named Wash-A-Lot-Bot detects a person’s hands in front of it via an ultrasonic sensor, then ticks a dial timer from 0 to 20 (or rather 20 to DONE!) using a micro servo. 

This simple setup can be made with little more than scissors and tape, making it a great way to learn about Arduino and programming while you’re stuck indoors.

Combating COVID-19 Conference: A Collaborative Arduino Community Initiative 
to take place on April 2nd at 5pm CET

Humanity is facing one of the most trying events in its history and as technologists, makers and designers we are asking ourselves how can we help. 

How can we contribute to the efforts to save lives, to help our fellow human beings?

All of us have been thinking about this and observing what was going on in the world.

We have seen communities, including the Arduino community, trying to design devices that would help hospitals cope with the lack of equipment; we’ve seen people firing up their imagination and their 3d printers in an effort to build something that could save even a single human life.

Having noticed that a large number of these efforts are using Arduino technology we reached out to a number of these communities to offer our help, donate some hardware, provide engineering support and do whatever we can considering that we are a small company.

One thing that was striking to us is the large amount of duplication in the work people are doing – many people are spending valuable time trying to overcome similar challenges in their design, rather than sharing their solution to the benefit of all and moving on to the next hurdle. Also that there are different teams with different strengths and skill sets that would be better working together than apart.

We must do better, be more effective, work together and merge efforts to solve these problems and reach our common goal quicker and more efficiently.

Because of all of this we want to invite as many of these projects as possible to an online gathering, to get people talking, to offer help on how to design and make hardware, how to think about the software, and how to scale manufacturing (we would like to share our knowledge in making tens of thousands of open source boards per week). Finally and most importantly we must take guidance from  medical professionals so that they can steer requirements and validate the designs so our efforts have the most positive impact. 

Join us online on April, 2nd to understand how we can work together to do better together, and Together – Let’s Make Covid-19 History

David Cuartielles, Massimo Banzi co-founders of Arduino (on behalf of Arduino)

Combating COVID-19 Conference: A Collaborative Arduino Community Initiative
will take place on April 2nd at 17.00 CET.

This is an open invitation to anyone currently using Arduino compatible devices within a project to design and manufacture ventilators, respirators or other devices to combat COVID-19. Be you a doctor, an academic, a professional company/researcher or an innovator you are more than welcome to join the conference. 

The conference will be hosted in Zoom (link available soon), with the ability to interact with Arduino and other members on the conference via Discord (free download here). 

There are different ways to participate in the conference; you can present your Arduino based project to combat COVID-19, support other community projects or provide expert advice – we are all stronger together.

(N.B. if you want to present and share your project, please complete this form by 12.00 (noon) CET on April 2nd)

More information on the conference will be available soon, in the meantime you can learn more about Arduino’s overall response to COVID-19 emergency here.

In ridiculous times, it can help to play ridiculous instruments such as the slide whistle to keep your bristles in check. But since spittle is more than a little bit dangerous these days, it pays to come up with alternative ways to play away the days during lockdown life.

Thanks to some clever Arduino-driven automation, [Gurpreet] can maintain a safe distance from his slide whistle while interacting with it. Slide whistles need two things — air coming in from the top, and actuation at the business end. The blowing force now comes from a focused fan like the ones that cool your printed plastic as soon as the hot end extrudes it. A stepper motor moves the slide up and down using a printed rack and pinion.

Here’s a smooth touch — [Gurpreet] added a micro servo to block and unblock the sound hole with a cardboard flap to make the notes more distinct. Check out the build video after the break, which includes a music video for “My Heart Will Go On”, aka the theme from Titanic. It’s almost like the ship herself is playing it on the steam whistles from the great beyond.

Speaking of, did you hear about the effort to raise and restore the remains of her radio room?

Looking to sterilize something? Give it a good blast of the old UV-C. Ultraviolet radiation in the shortest wavelength band breaks down DNA and RNA, so it’s a great way to kill off any nasties that are lurking. But how much UV-C are you using? [Akiba] at Hackerfarm has come up with the NukeMeter, a meter that measures the output of their UV-C sterilizer the NukeBox. It is built around a $2.50 sensor and a $3 Arduino.

The NukeMeter is built around a GUVA-S12SD UV sensor breakout board. This sensor is really designed for UV-A detection, but a quick look at the spec sheet revealed that it is sensitive to UV across all of the bands. So, it can be used as a UV-C sensor if you know how sensitive it is to this particular frequency band.

However, the sensor is not that sensitive to UV-C light, so [Akiba] had to do a bit of minor surgery on the circuitry that surrounds the sensor to tweak the output. The sensor was designed to measure relatively low levels of UV light (such as sunlight), and now they are blasting it with a shedload of radiation, so they have to effectively disable one of the op-amps that normally scales the output up, which involves replacing a couple of resistors. That’s a bit of a pain to do with surface mount components, but it is doable with a steady hand and a small tip soldering iron.

Next, an Arduino takes the voltage output of the sensor and converts it into a light level. The mathematics of how this works are all well detailed in the post, but it isn’t complicated, and the source code is here.

Using this, [Akiba] was able to measure how the lights performed, how quickly they warmed up and how much the light level varies along the length of the fluorescent tube.

One caveat to bear in mind here: [Akiba] designed this to measure the output of the low-pressure mercury vapor lamps they are using at Hackerfarm, which output a very narrow frequency band, peaking at 250 nM. This design would not work for a more broadband output or for one which mixed UV-C with UV-A and UV-B. For that, you would need a more sophisticated design that would probably cost more than $5.

SAFETY NOTE: Don’t mess with UV-C light sources unless you have a good idea of what you are doing and are sure that the light is contained, e.g. in a sealed box, maybe with interlocks. Remember that you also rely on DNA, and inadvertently zapping your own DNA can cause all sorts of unpleasantness.  

We once saw a Romeo and Juliet production where the two families were modern-day mob families with 3-piece suits and pistols. If they made King Richard III set in this week, the famous line might be: “Hand sanitizer, hand sanitizer, my kingdom for hand sanitizer!” Even if you have a supply stashed in your prepper cache, you have to touch the bottle so you could cross-contaminate with other users. Public places often have automatic dispensers to combat this, and now you can too. [Just Barran] shows the device in a video, you can see below.

Sourcing parts for projects is sometimes a problem, but right now we are betting the hand sanitizer will be the hardest component. Of course, the Internet is ripe with homemade brews that may or may not be effective based on beer, grain alcohol, or a variety of other base materials.

[Barran] has a big junk box. so he snagged an Arduino and an ultrasonic sensor. The part that is a little tricky is pulling down the pump. The basic idea is to use a servo motor to pull some fishing line. To engage the bottle, there is a small bit of plastic from a notebook cover and the fishing line goes to both sides of it. One side of the fishing line is fixed and the other is what the servo pulls.

We might have used a solenoid to push the button, but we like the servo method for its simplicity. In the end, it does look like it works well. Changing the bottle out probably requires a little surgery since there is a screw holding the plastic bracket in and you might have to update the fishing line lengths. That might be an impediment for a commercial project, but for your own use, it doesn’t seem like it would be a problem.

Fishing line is more useful than you might think. We’ve even seen it used as belts in 3D printers.

Whether it’s with an old friend or new acquaintance, we’ve all had those awkward gaps in conversation. Do you speak next, or let the other person lead the discussion? If that’s not happening naturally, then SASSIE, or “System for Awkward Silence Solution and Interaction Enhancer,” is here to help.

The cylindrical device detects audio feedback via a pair of microphones positioned near each person in a conversation. When a sufficient silence is detected, SASSIE pops a flag out and rotates to indicate who needs to talk. If that wasn’t enough of a hint, it also audibly tells that person to say something. 

SASSIE is powered by dual Arduino Uno boards, one of which takes care of the bulk of the control functions, while the other actuates the stepper to spin the top indicator.