Day: February 2, 2021

Art of 3D printer in the middle of printing a Hackaday Jolly Wrencher logo

3D Printering: Why Aren’t Enclosures Easier?

February 2, 2021 by 100 Comments

For 3D printers that aren’t already enclosed, why is easily adding a cheap and effective enclosure still not a completely solved problem? The reason is simple: unless one’s needs are very basic, enclosures are more than just boxes.

Different people need different features, printers come in different shapes and sizes, and creating something that can be both manufactured and shipped cheaply is a challenge in itself. In this article I’ll explain how those things make boxing up your printer a tougher nut to crack then may seem at first glance.

Enclosures Have Different Jobs

People have different expectations of what an enclosure’s job should be, and that determines which features are important to them and which are not. Here is a list of meaningful features for 3D printer enclosures; not everything on this list is important to everyone, but everything on this list is important to someone. Continue reading “3D Printering: Why Aren’t Enclosures Easier?” →

“Alexa, Stop Listening To Me Or I’ll Cut Your Ears Off”

February 2, 2021 by 88 Comments

Since we’ve started inviting them into our homes, many of us have began casting a wary eye at our smart speakers. What exactly are they doing with the constant stream of audio we generate, some of it coming from the most intimate and private of moments? Sure, the big companies behind these devices claim they’re being good, but do any of us actually buy that?

It seems like the most prudent path is to not have one of these devices, but they are pretty useful tools. So this hardware mute switch for an Amazon Echo represents a middle ground between digital Luddism and ignoring the possible privacy risks of smart speakers.  Yes, these devices all have software options for disabling their microphone arrays, but as [Andrew Peters] relates it, his concern is mainly to thwart exotic attacks on smart speakers, some of which, like laser-induced photoacoustic attacks, we’ve previously discussed. And for that job, only a hardware-level disconnect of the microphones will do.

To achieve this, [Andrew] embedded a Seeeduino Xiao inside his Echo Dot Gen 2. The tiny microcontroller grounds the common I²S data line shared by the seven (!) microphones in the smart speaker, effective disabling them. Enabling and disabling the mics is done via the existing Dot keys, with feedback provided by tones sent through the Dot speaker. It’s a really slick mod, and the amount of documentation [Andrew] did while researching this is impressive. The video below and the accompanying GitHub repo should prove invaluable to other smart speaker hackers.

Continue reading ““Alexa, Stop Listening To Me Or I’ll Cut Your Ears Off”” →

DVD Optics Power This Scanning Laser Microscope

February 2, 2021 by 35 Comments

We’ve all likely seen the amazing images possible with a scanning electron microscope. An SEM can yield remarkably detailed 3D images of the tiniest structures, and they can be invaluable tools for research. But blasting high-energy cathode rays onto metal-coated samples in the vacuum chamber of a bulky and expensive instrument isn’t the only way to make useful images, as this home-brew laser scanning microscope demonstrates.

This one comes to us by way of [GaudiLabs], a Swiss outfit devoted to open-source lab equipment that enables citizen science; we saw their pocket-sized thermal cycler for PCR a while back. The basic scheme here is known as confocal laser scanning fluorescence microscopy, where a laser at one wavelength excites fluorescent tags bound to structures in a sample. Light emitted by the tags is collected, and a 3D image is built up from multiple scans of the sample at different focal planes.

Like many DIY projects, this microscope is built from old DVD parts, specifically the pickup heads. The precision optics in these commonly available assemblies, which are good enough to read pits as small as 150 nm on a Blu-Ray DVD, are well-suited for resolving similarly sized microstructures. One DVD pickup is used to scan the laser in the X-axis, while the other head is modified to carry the sample and move it in the Y-axis. The pickup head coils and laser are driven by an Arduino carried on a custom PCB along with the DVD heads. Complete build files are posted on GitHub for anyone interested in recreating this work.

We love tips like this that dig back a bit and find things we missed the first go-around. And the equipment [GaudiLabs] lists really has potential for the budding biohacker, which we also like.

Thanks for the tip on this one, [Bill].