Workbench Fume Extractor Sucks, But Has A Charming Personality

Shop safety is important regardless of what kind of work you do. For those of us soldering, that means extracting the noxious fumes released by heating up the solder flux used in our projects. [yesnoio] brings to us his own spin on the idea of a fume extractor, and it pulls out all stops with bells and whistles to spare.

The Workbench Assistant bot, as [yesnoio] describes it, is an integrated unit mounted atop a small tripod which extends over the working area where you’re soldering. Inside the enclosure are RGBW lights, an IR camera, and an Adafruit ItsyBitsy M4 Express driving the whole show. Aside from just shining a light onto your soldering iron though, the camera senses thermal activity from it to decide when to ramp up the server-grade fan inside which powers the whole fume extraction part of the project.

But the fun doesn’t stop there, as [yesnoio] decided to go for extra style points. The bot also comes with an amplified speaker, playing soundbites whenever actions such as starting or stopping the fan are performed. These soundbites are variations on a theme, like classic Futurama quotes or R2-D2’s chattering from Star Wars. The selectable themes are dubbed “performers”, and they can be reprogrammed easily using CircuitPython. This is a neat way to give your little desktop assistant some personality, and a fun way to break up the monotony of soldering up all those tiny SMD components on your next prototype.

If even after all this you still need more than just a cute little robotic voice beeping at you to convince you to get a fume extractor for your bench, then maybe some hands-on results could give you that little push you need. And if you’re already convinced and want to build your own, there is no shortage of DIY solutions we’ve seen around here at Hackaday. Check out this one in action after the break!

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Embed With Elliot: Audio Playback With Direct Digital Synthesis

Direct-digital synthesis (DDS) is a sample-playback technique that is useful for adding a little bit of audio to your projects without additional hardware. Want your robot to say ouch when it bumps into a wall? Or to play a flute solo? Of course, you could just buy a cheap WAV playback shield or module and write all of the samples to an SD card. Then you wouldn’t have to know anything about how microcontrollers can produce pitched audio, and could just skip the rest of this column and get on with your life.

Harmonic distortion down ~45db on an Arduino
~45db signal to noise ratio from an Arduino

But that’s not the way we roll. We’re going to embed the audio data in the code, and play it back with absolutely minimal additional hardware. And we’ll also gain control of the process. If you want to play your samples faster or slower, or add a tremolo effect, you’re going to want to take things into your own hands. We’re going to show you how to take a single sample of data and play it back at any pitch you’d like. DDS, oversimplified, is a way to make these modifications in pitch possible even though you’re using a fixed-frequency clock.

The same techniques used here can turn your microcontroller into a cheap and cheerful function generator that’s good for under a hundred kilohertz using PWM, and much faster with a better analog output. Hackaday’s own [Bil Herd] has a nice video post about the hardware side of digital signal generation that makes a great companion to this one if you’d like to go that route. But we’ll be focusing here on audio, because it’s easier, hands-on, and fun.

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