Design For 3D Printing Hack Chat

Join us on Wednesday, May 24 at noon Pacific for the Design for 3D Printing Hack Chat with Eric Utley!

Like a lot of enabling technologies, 3D printing has had a strange trajectory. It started out as a laboratory oddity, moved on to industrial applications, and finally filtered down to the DIY set, first as scratch-built machines and later as inexpensive commodity printers that can be found almost anywhere. Pretty much everyone who needs a 3D printer now has one.

Not all additive manufacturing technologies are created equal, though, and there are plenty of applications for 3D printed parts where FDM just won’t cut it. Luckily, any of us can get access to the latest and greatest manufacturing technologies through job houses that specialize in everything from metal 3D printing to sheet metal fabrication, CNC machining, and even small-run injection molding. We may not be able to afford any of the machines, but in a lot of cases we can afford to rent time of them and get high-quality parts quickly.

join-hack-chatBut that raises another question: Is my design ready for printing? What works on an Ender on your shop bench might not quite translate to the latest SLS printer, and sending off an iffy design could just end up wasting time and money. Whether you’re sending your designs out and running them up on your own printer, you want to know what you’re doing will work. That’s why we’ve asked Eric Utley, an applications engineer with Protolabs, to stop by the Hack Chat. With 12 years of additive manufacturing experience, he’ll be able to help you tune up your designs and make sure they’re ready to print.

Our Hack Chats are live community events in the Hackaday.io Hack Chat group messaging. This week we’ll be sitting down on Wednesday, May 24 at 12:00 PM Pacific time. If time zones have you tied up, we have a handy time zone converter.

Click that speech bubble to the right, and you’ll be taken directly to the Hack Chat group on Hackaday.io. You don’t have to wait until Wednesday; join whenever you want and you can see what the community is talking about.

Hoverboard Rides On Eddy Currents

The famous hoverboards of Back to the Future haven’t quite gotten here yet, but that hasn’t stopped anyone with a unique personal vehicle from using the name any time they need some quick marketing. The self-balancing scooter trend of the mid-2010s was the best example of this in recent memory, but there are also water-propelled platforms that use the popular name as well as a myriad of other more skateboard-like devices that never got off the ground at all. This project from [Damien Dolata], on the other hand, might be the most authentic prototype we’ve seen compared against the fictional version presented in the movie.

The hoverboard uses a set of rotating magnets, referred to in this build as magneto-rotational repulsors, which spin up to an extremely high rotational speed underneath the board. When above a metal surface, the spinning magnets generate eddy currents in the metal beneath them which create the strong magnetic field needed to levitate the board. Unlike the Lexus hoverboard system which used supercooling magnets, this is a much more affordable way of producing magnetic fields but is a little bit more complicated due to the extra moving parts.

As this is still in the prototyping stages, it has only been able to lift around 30 kg and hasn’t been tested in motion yet, but there are two small turbines built into the hoverboard to generate thrust whenever [Damien] gets to that point. It would require a larger metal surface to move across as well, which might be the main reason why it hasn’t been tested this way yet. For any native French speakers taking a look at this project, be sure to fill in any of our gaps in the comments below, and for other ways that eddy currents have been used in transportation take a look at this bicycle that uses them in its drivetrain.

Continue reading “Hoverboard Rides On Eddy Currents”

AirTags, Tiles, SmartTags And The Dilemmas Of Personal Tracking Devices

In an ideal world we would never lose our belongings, and not spend a single hour fruitlessly searching for some keys, a piece of luggage, a smartphone or one of the two dozen remote controls which are scattered around the average home these days. Since we do not live in this ideal world, we have had to come up with ways to keep track of our belongings, whether inside or outside our homes, which has led to today’s ubiquitous personal tracking devices.

Today’s popular Bluetooth-based trackers constantly announce their presence to devices set up to listen for them. Within a home, this range is generally enough to find the tracker and associated item using a smartphone, after which using special software the tracker can be made to sound its built-in speaker to ease localizing it by ear. Outside the home, these trackers can use mesh networks formed by smartphones and other devices to ‘phone home’ to paired devices.

This is great when it’s your purse. But this also gives anyone the ability to stick such a tracker device onto a victim’s belongings and track them without their consent, for whatever nefarious purpose. Yet it is this duality between useful and illegal that has people on edge when it comes to these trackers. How can we still use the benefits they offer, without giving stalkers and criminals free reign? A draft proposal by Apple and Google, submitted to the Internet Engineering Task Force (IETF), seeks to address these points but it remains complicated.

Continue reading “AirTags, Tiles, SmartTags And The Dilemmas Of Personal Tracking Devices”

ChatGPT Rules The World… Or, At Least, The Home

With all the hype about ChatGPT, it has to have crossed your mind: how can I make it control devices? On the utopia side, you could say, “Hey, ChatGPT, figure out what hours I’m usually home and set the thermostat higher when I am away.” On the dysfunctional side, the AI could lock you in your home and torment you like some horror movie. We aren’t to either extreme yet, but [Chris] couldn’t resist writing a ChatGPT plugin to control a Raspberry Pi. You can see a video of how it turned out below.

According to [Chris], writing a ChatGPT plugin is actually much simpler than you think. You can see in the video the AI can intuit what lights to turn on and off based on your activity, and, of course, many more things are possible. It can even detect snoring.

Continue reading “ChatGPT Rules The World… Or, At Least, The Home”

The Wizard Of Semiconductors

If you have three hours and you want to learn the fundamentals of semiconductors, [Tiny Tapeout] has something for you: An introduction to SiliWiz. You’ll also need the SiliWiz software (or use it online), which resembles the kind of tools that chip designers use but is meant for students to use as a learning tool

Using SiliWiz, you create layers on a virtual device, and you can use Spice to view the results. The tutorial is meant to be high-level and is suggested for students aged 14 or over (but we liked it and we are quite a bit older than that). Some more advanced material is also available at the same site.

Continue reading “The Wizard Of Semiconductors”

We’ve Got A Saxaboom At Home Son

Most parents have heard a familiar story. Their lovely child comes up, having seen a celebrity rocking out with a funny $20 toy from the 80s, and asks for it. Of course, you reply, it’s just 20 dollars. However, a quick scan through eBay reveals that everyone else’s kid has also been asking for this obscure toy for a school event, which now costs around $700. [Ben] found himself in that exact position and made a crucial off-hand comment, “I bet I could make one of those.” That was how his hectic journey into the world of toy reproduction began.

All [Ben] had for reference when recreating a Sax-A-Boom were pictures and sound clips. Modeling complex sweeping shapes in CAD is difficult, and [Ben] commissioned a 3d model from a professional on Fiverr. [Ben] broke down the model into printable sections and tweaked it to account for buttons. After a concerning amount of putty, wet sanding, and elbow grease, [Ben] had a decently smooth body for an instrument. The device’s guts is an ESP32-based board called Sonatino, built around music generation. The music samples came from a virtual instrument clone on GitHub and loaded onto an SD card.

Time pressure crept in towards the end, and [Ben] had to go for some dirty solution that he would have preferred (popsicle sticks and epoxy for button mounting). Yes, there were some gaps and paint flaws, but ultimately [Ben’s] son rocked the school presentation. It’s a beautiful journey through creating something with a high level of finish on a limited timescale.

Perhaps future versions of the Sax-A-Boom can take it further by adding a breath sensor, like this 3d printed MIDI instrument.

Continue reading “We’ve Got A Saxaboom At Home Son”

Watch A Web Page Fetch Itself Over TLS, Complete With Commentary

TLS, byte by byte performs an unusual and interesting function: it fetches itself over HTTPS, and provides a complete annotation of what’s going on in the process, one byte at a time. Visit the site and give the button a click to watch it happen, it’s neat!

Transport Layer Security (TLS) is what’s responsible for encrypting traffic over the internet, and it’s normally implemented on top of TCP to encrypt an application-layer protocol like HTTP (resulting in HTTPS and the little padlock icon in browsers indicating a connection with a web site is encrypted.) Back in the day, traffic over the internet was commonly unencrypted, but nowadays no communication or hardware is too humble for encryption and methods are easily accessible.

So for what purpose would someone actually need or use such an implementation of TLS? Well, probably no one actually needs it. But it is a userspace TLS implementation in javascript that may fit a niche for someone, and it certainly provides beautifully-indented and annotated binary data in the process. Sound up your alley? The GitHub repository for the project has all the details, so give it a look.