Tiny Typing Tutor Tuts At Your Incorrect Shift Usage

February 13, 2025 by Lewin Day 16 Comments

There are a wide range of typing tutors out there that will educate you in the glorious skill of touch-typing. Many just focus on the basics, ranking you on accuracy and speed. However, there’s a nifty little online tutor that can help you with one skill specifically—it’s aim is to teach you to use the Shift keys “properly.”

The tutor is the work of [KaarelP2rtel]. The unnamed tool is intended to guide you into instinctively using both the left and right Shift keys as you type. Many typers default to using one or the other. This can lead to fumbles and slowdown when one hand is trying to hit both the Shift key and a letter.

[KaarelP2rtel]’s belief is that the “correct” method is to press the Shift key with the opposite hand to the one typing the letter, and this typing tutor enforces that practice. You must type repeated capitalized words one after the other, and you’ll only progress quickly if you’re hitting the opposite Shift key each time. Unconventional keyboardists fear not—you can convert the tool to work with Dvorak or Colemak layouts if necessary.

Is this a crucial tool for the fast typist? The jury’s out on that one. It’s entirely possible to hit in excess of 120 wpm without this technique for most normal passages of text, using dynamic finger reassignments when hitting Shift with the same hand. Still, the diligent may find it a useful upgrade to their existing typing abilities.

Source code is on GitHub for the curious. Notably, it’s a very small website that weighs in at just a few kilobytes; it would be a rather fitting part of the Small Web, which we’ve explored before!

A Transparent BB-8 Build Using Christmas Ornaments

February 13, 2025 by Lewin Day 10 Comments

The cool thing about the droids of Star Wars is that they’re not that hard to recreate in real life. R2-D2 is a popular choice, but you can even build yourself a neat little BB-8 if you’re so inclined. [Piyush] has built a particularly compelling example that’s transparent, which lets you see the internals and how it all works.

The build makes creative use of a pair of Christmas ornaments. They are perhaps the cheapest and easiest way to source a clear plastic sphere. One serves as the “head”, while the other serves as the larger spherical body. Inside, an Arduino Pro Micro is running the show. It’s hooked up to a L293D motor driver which runs the drive motors and the reaction wheel motor which provides stability, while a separate MOSFET is on hand to run the gear motor which controls the head.

There’s also an HC-05 module for Bluetooth communication, and a BNO055 sensor for motion tracking and ensuring the robot stays the right way up. 3D printed components are used prodigiously to cram everything together tightly enough to fit. There’s even a printed charging base to juice up the little droid. Controlling the robot is as simple as using a smartphone with an app created in the MIT App Inventor.

If you’ve never built a spherical rolling robot before—and few of us have—this design is a great reference for your own work. We’ve seen a few BB-8s over the years, most of which dropped shortly after the movie was released. Continue reading “A Transparent BB-8 Build Using Christmas Ornaments” →

Automatic Pill Dispenser Is Cheap And Convenient

February 12, 2025 by Lewin Day 20 Comments

If you’re taking any medication, you probably need to take it in a certain dose on a certain schedule. It can quickly become difficult to keep track of when you’re taking multiple medications. To that end, [Mellow_Labs] built an automated pill dispenser to deliver the right pills on time, every time.

The pill dispenser is constructed out of 3D printed components. As shown, it has two main bins for handling two types of pills, controlled with N20 gear motors. The bins spin until a pill drops through a slot into the bottom of the unit, with the drop detected by a piezo sensor. It uses a Beetle ESP32 as the brains of the operation, which is hooked up with a DS1307 real-time clock to ensure it’s dosing out pills at the right time. It’s also wired up with a DRV8833 motor driver to allow it to run the gear motors. The DRV8833 can run up to four motors in unidirectional operation, so you can easily expand the pill dispenser up to four bins if so desired.

We particularly like how the pill dispenser is actually controlled — [Mellow_Labs] used the ESP32 to host a simple web interface which is used for setting the schedule on which each type of pill should be dispensed.

We’ve featured some other pill dispenser builds before, too.

Continue reading “Automatic Pill Dispenser Is Cheap And Convenient” →

Blinds Automated With Offline Voice Recognition

February 10, 2025 by Lewin Day 7 Comments

Blinds are great for keeping light out or letting light in on demand, but few of us appreciate having to walk over and wind them open and shut on the regular. [DIY Builder] resented this very task, so set about creating an automated system to do the job for him.

The blinds in question use a ball chain to open and close, which made them relatively easy to interface with mechanically. [DIY Builder] set up a NEMA 17 stepper motor with an appropriate 3D-printed gear to interface with the chain, allowing it to move the blinds accurately. The motor is controlled via an Arduino Nano and an A4988 stepper motor driver.

However, that only covered the mechanical side of things. [DIY Builder] wanted to take the build a step further by making the blinds voice activated. To achieve this, the Arduino Nano was kitted out with a DFRobot Gravity voice recognition module. It’s a super simple way to do voice recognition—it’s an entirely offline solution with no cloud computing or internet connection required. You just set it up to respond to simple commands and it does the rest.

The result is a voice activated blind that works reliably whether your internet is up or not. We’ve seen some other great projects in this space, too. Video after the break.

Continue reading “Blinds Automated With Offline Voice Recognition” →

Tiny Mouse Ring Uses Prox Sensors

February 10, 2025 by Lewin Day 11 Comments

A traditional computer mouse typically fits in the palm of your hand. However, with modern technology, there’s no need for mice to be so large, as demonstrated by [juskim]’s neat little mouse ring. Check it out in the video below.

The concept is simple—it’s a tiny mouse that sits neatly on the end of one of your fingers. You then get the slightly surreal experience of pointing on your computer just by moving a single finger instead of your whole hand.

The project uses a typical optical mouse sensor for movement, as you might expect. However, there are no conventional switches for the left and right mouse buttons. Instead, [juskim] realized a more compact design was possible by using proximity sensors instead. The sensors detect the presence of his fingers on either side of the ring mouse. When one of the fingers is lifted, the absence of the finger triggers a mouse click, either left or right, depending on the finger.

The build started with junk box parts, but hooking up an Arduino Pro Micro dev board and other modules proved too cumbersome to use effectively. Instead, the build relies on an ATTO board, a tiny PCB featuring the same ATmega32U4 microcontroller. Similarly, the build relies on tiny proximity sensors from STM to fit in the “ring” form factor. It’s all wrapped up in a 3D-printed enclosure that fits snugly on the user’s finger.

We’ve seen some other neat mouse rings before, too. Or, if you want something really different, grab some keychains and make a 6DOF mouse.

Continue reading “Tiny Mouse Ring Uses Prox Sensors” →

How Magnetic Fonts Twisted Up Numbers And Saved Banking Forever

February 10, 2025 by Lewin Day 48 Comments

If you’ve ever looked at the bottom of a bank check, you probably glanced over some strangely formed numbers? If you’re a fan of science fiction or retro computers, you’ve probably spotted the same figures on any number of books from the 1980s. They’re mostly readable, but they’re chunky and thin in places you don’t expect.

Those oddball numerals didn’t come from just anywhere—they were a very carefully crafted invention to speed processing in the banking system. These special fonts were created to be readable both by humans and machines—us with our eyes, and the computers with magnetic sensors. Let’s explore the enigmatic characters built for Magnetic Ink Character Recognition (MICR). Continue reading “How Magnetic Fonts Twisted Up Numbers And Saved Banking Forever” →

Flip Flops Make Great Soft Switches

February 10, 2025 by Lewin Day 46 Comments

Mechanical switches are pretty easy to understand—the contacts touch, the current flows, and Bob is, presumably, your uncle. But what about soft switches? Well, they’re not that difficult to understand either, as explained by [EDN].

*You can build a touch switch quite easily with old-school chips.*

The traditional softswitch takes input from a momentary single-pole pushbutton and lets you press to toggle power on and off. This operation is easy to achieve with a simple flip-flop constructed with old-school logic to create a “bistable” circuit. That means it will happily remain stable in one of two states unless you do something to make it switch.

Continue reading “Flip Flops Make Great Soft Switches” →