A Look At 3D Printed Shoes: Hybrid, Fully Printed And Plain Weird

May 25, 2024 by Maya Posch 7 Comments

In the eternal quest to find more things to do with 3D printers, shoes have been in the spotlight for a while now. But how practical is additive manufacturing in this field really?

Adidas Ultra 4D running shoes with 3D printed midsole.

This is where [Joel Telling] of the 3D Printing Nerd YouTube channel puts in his two cents, with a look at a range of commercial and hobbyist ideas and products. Naturally, the first thing that likely comes to mind at the words ‘3D printed shoes’ is something akin to the plastic version of wooden clogs, or a more plastic-y version of the closed-cell resin of Crocs.

First on the list are the white & spiky Kaiju Gojira shoes from Fused Footwear, printed from TPE filament to order. TPE is softer to the touch and more flexible than TPU, but less durable. In contrast the Adidas Ultra 4D running shoes (from their 4D range) are a hybrid solution, with a standard rubber outsole, 3D printed midsole with complex structures and mostly fabric top part. Effectively a Nike Air in initial impression, perhaps.

Meanwhile ‘3D printed’ shoes ordered off Chinese store Shein turned out to be not 3D printed at all, while [Joel] seems to be really into fully 3D printed shoes from Zellerfeld, who appear to be using TPU. While it’s hard to argue about taste, the Adidas shoes might appeal to most people. Especially since they’d likely let your feet breathe much better, a fact appreciated not only by yourself, but also family members, roommates and significant others. So which of these (partially) 3D printed shoes would you pick, or do you have some other favorite?

Continue reading “A Look At 3D Printed Shoes: Hybrid, Fully Printed And Plain Weird” →

Everything You Ever Wanted To Know About The ULN2003

May 25, 2024 by Donald Papp 27 Comments

The ULN2003 IC is an extremely versatile part, and with the help of [Hulk]’s deep dive, you might just get some new ideas about how to use this part in your own projects.

Each of the seven outputs works like this simplified diagram.

Inside the ULN2003 you’ll find seven high-voltage and high-current NPN Darlington pairs capable of switching inductive loads. But like most such devices there are a variety of roles it can fill. The part can be used to drive relays or motors (either brushed or stepper), it can drive LED lighting, or simply act as a signal buffer. [Hulk] provides some great examples, so be sure to check it out if you’re curious.

Each of the Darlington pairs (which act as single NPN transistors) is configured as open collector, and the usual way this is used is to switch some kind of load to ground. Since the inputs can be driven directly from 5 V digital logic, this part allows something like a microcontroller to drive a high current (or high voltage, or both) device it wouldn’t normally be able to interface with.

While the circuitry to implement each of the transistor arrays isn’t particularly complex and can be easily built by hand, a part like this is a real space saver due to how it packs everything needed in a handy package. Each output can handle 500 mA, but this can be increased by connecting in parallel.

There’s a video (embedded below) which steps through everything you’d like to know about the ULN2003. Should you find yourself wanting a much, much closer look at the inner secrets of this chip, how about a gander at the decapped die?

Continue reading “Everything You Ever Wanted To Know About The ULN2003” →

BASIC Classroom Management

May 25, 2024 by Bryan Cockfield 22 Comments

While we don’t see it used very often these days, BASIC was fairly revolutionary in bringing computers to the masses. It was one of the first high-level languages to catch on and make computers useful for those who didn’t want to (or have time) to program them in something more complex. But that doesn’t mean it wasn’t capable of getting real work done — this classroom management software built in the language illustrates its capabilities.

Written by [Mike Knox], father of [Ethan Knox] aka [norton120], for his classroom in 1987, the programs were meant to automate away many of the drudgeries of classroom work. It includes tools for generating random seating arrangements, tracking attendance, and other direct management tasks as well as tools for the teacher more directly like curving test grades, tracking grades, and other tedious tasks that normally would have been done by hand at that time. With how prevalent BASIC was at the time, this would have been a powerful tool for any educator with a standard desktop computer and a floppy disk drive.

Since most people likely don’t have an 80s-era x86 machine on hand capable of running this code, [Ethan] has also included a docker container to virtualize the environment for anyone who wants to try out his father’s old code. We’ve often revisited some of our own BASIC programming from back in the day, as our own [Tom Nardi] explored a few years ago.

Hype Robot Rocks Out With The Twitch Chat

May 25, 2024 by Lewin Day 1 Comment

Have you ever wished for an automaton that can get the party started, raise the roof, and all that? You’ll want to meet [DJ Pfeif]’s Flippin Rhobot, then. He’s a hype bot from the world of Twitch streaming, and he apparently knows how to party.

Flippin Rhobot is controlled by an ESP32 that listens into the chat on [DJ Pfeif]’s stream. He’s got a vaguely humanoid form, and he can rotate on the spot and wave his arms in the air courtesy of a few servos. He’s also got a little computer terminal that displays the show’s “Hack the Planet” logo when he turns to face the screen. His body also features some addressable LEDs that flash and dance on command.

[DJ Pfeif] does a good job of explaining the project, and includes the code that laces everything together. Interfacing with Twitch chat can be fun, and we’ve featured a guide on doing just that before, too.

If you’re building your own roboticized hype machine, don’t hesitate to let us know. Otherwise, consider musing on the very idea of humanoid robots as a whole!

Linear LED clock displaying the time using different-colored triangles.

Linear LED Clock Looks Decidedly Vintage

May 24, 2024 by Kristina Panos 3 Comments

We just love a good clock around here, and something about those triangles gives this linear LED clock a deliciously mid-century vibe. If you’ve read these pages for any length of time, you know that [andrei.erdei] loves clocks as much as we do, and is always coming up with interesting ways of displaying the passage of time.

This one is a remix of some other linear RGB clocks, but the result is distinctly [andrei.erdei]’s style. There’s nothing crazy going on under the hood here — it’s essentially a Wemos D1 mini running a strip of RGBs, and the microcontroller connects to a Wi-Fi router to get the time from a server. The magic is in the programming and the way the clock is read.

The brief but thorough demo video after the break does a much better job of explaining the display by showing various times of the day, but we’ll give it a shot. For one thing, it uses 24-hour time exclusively. There are four groups of triangles; yellow, red, green, and blue which correspond to tens and units of hours, and tens and units of minutes.

The triangles light up in groups of three in the order depicted in the animation. At midnight, none of the triangles are lit up. Again, it’s best explained in the video, looking at various times of day. Plus you can see the neat-o startup animation.

Are you more into sound than blinkenlights? Then this customizable bird clock may be for you.

Continue reading “Linear LED Clock Looks Decidedly Vintage” →

Regular Expressions Finally Come To Microsoft Excel

May 24, 2024 by Dan Maloney 29 Comments

There are two types of people in the world: those who have no idea what a regular expression is, and those who not only know what they are but can compose them on the fly and tend to use them in situations where they’re clearly not called for. And it’s that latter camp, of which we consider ourself a proud member, that is rejoicing with the announcement that Microsoft is adding regular expression support to Excel.

Or perhaps not rejoicing so much as wondering what took so long. Yes, regular expressions have been part of VBA for a while now, but the new functions allow you to use regexes right in the spreadsheet grid. There are plenty of caveats, of course. The big one is that this is still in beta at this time, so you have to do some gymnastics to enable it, if you’re even allowed to in the first place. Second, support appears limited to three functions at the moment: REGEXTEST, which provides a logical test of pattern matching; REGEXEXTRACT, which returns a substring that matches a pattern; and REGEXREPLACE, which substitutes a string for a pattern. The video below walks through how to use these functions within spreadsheets.

What’s also unclear now is what flavor of regular expressions is supported. There are a bewildering number of entities in the regex bestiary — character classes, positional indicators, quantifiers, subexpressions, lazy and greedy matches, and a range of grouping constructs that perplex even regex pros. One hopes these new functions will support one of the existing regex standards, but Microsoft is famous for “extending and enhancing.” Then again, regex support has been in the .NET Framework for years and is pretty close to the Perl standard, so our guess is that it’ll be close to that.

If you fall into the “What’s a regex?” camp but want to change that, why not get your grep on?

Continue reading “Regular Expressions Finally Come To Microsoft Excel” →

Twelve pink tentacles are wrapped around a small, green succulent plant. The leaves seem relatively undisturbed. They are dangling from brass and white plastic pressure fittings attached to a brass circle.

Tentacle Robot Wants To Hold You Gently

May 24, 2024 by Navarre Bartz 16 Comments

Human hands are remarkable pieces of machinery, so it’s no wonder many robots are designed after their creators. The amount of computation required to properly attenuate the grip strength and position of a hand is no joke though, so what if you took a tentacular approach to grabbing things instead?

Inspired by ocean creatures, researchers found that by using a set of pneumatically-controlled tentacles, they could grasp irregular objects reliably and gently without having to faff about with machine learning or oodles of sensors. The tentacles can wrap around the object itself or intertwine with each other to encase parts of an object in its gentle grasp.

The basic component of the device is 12 sections “slender elastomeric filament” which dangle at gauge pressure, but begin to curl as pressure is applied up to 172 kPa. All of the 300 mm long segments run on the same pressure source and are the same size, but adding multiple sized filaments or pressure sources might be useful for certain applications.

We wonder how it would do feeding a fire or loading a LEGO train with candy? We also have covered how to build mechanical tentacles and soft robots, if that’s more your thing.

Continue reading “Tentacle Robot Wants To Hold You Gently” →