The Subtle Art Of Letterform Design

Typeface (such as Times New Roman) refers to the design that gives a set of letters, numbers, and symbols their signature “look”. Font, on the other hand, is a specific implementation of a typeface, for example, Times New Roman Italic 12 pt.

‘Q’ is a counterpoint to the idea that typography is just one fussy detail after another.

Right about this point, some of you are nodding along and perhaps thinking “oh, that’s interesting,” while the rest of you are already hovering over your browser’s Back button. If you’re one of the former, you may be interested in checking out the (sort of) interactive tour of typography design elements by the Ohno Type School, a small group that loves design.

On one hand, letters are simple and readily recognizable symbols. But at the same time, their simplicity puts a lot of weight on seemingly minor elements. Small changes can have a big visual impact. The tour lays bare answers to questions such as: What is the optimal parting of the cheeks of a capital ‘B’? At what height should the crossbar on an ‘A’ sit, and why does it look so weird if done incorrectly? And yet, the tail of a ‘Q’ can be just about anything? How and why does an ‘H’ define the spacing of the entire typeface? All these (and more) are laid bare.

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A Deep Dive Into The Coolness That Was CRT Projectors

CRT monitors: there’s nothing quite like ’em. But did you know that video projectors used to use CRTs? A trio of monochrome CRTs, in fact: one for each color; red, green, and blue. By their powers combined, these monsters were capable of fantastic resolution and image quality. Despite being nowhere near as bright as modern projectors, after being properly set up, [Technology Connections] says it’s still one of the best projected images he has seen outside of a movie theatre.

After a twenty-minute startup to reach thermal equilibrium, one can settle down with a chunky service manual for a ponderous calibration process involving an enormous remote control. The reward is a fantastic (albeit brightness-limited) picture.

Still, these projectors had drawbacks. They were limited in brightness, of course. But they were also complex, labor-intensive beasts to set up and calibrate. On the other hand, at least they were heavy.

[Technology Connections] gives us a good look at the Sony VPH-D50HT Mark II CRT Projector in its tri-lobed, liquid-cooled glory. This model is a relic by today’s standards, but natively supports 1080i via component video input and even preserves image quality and resolution by reshaping the image in each CRT to perform things like keystone correction, thus compensating for projection angle right at the source. Being an analog device, there is no hint of screen door effect or any other digital artifact. The picture is just there, limited only by the specks of phosphor on the face of each tube.

Converging and calibrating three separate projectors really was a nontrivial undertaking. There are some similarities to the big screen rear-projection TVs of the 90s and early 2000s (which were then displaced by plasma and flat-panel LCD displays). Unlike enclosed rear-projection TVs, the screen for projectors was not fixed, which meant all that calibration needed to be done on-site. A walkthrough of what that process was like — done with the help of many test patterns and a remote control that is as monstrous as it is confusing — starts at 15:35 in the video below.

Like rear-projection TVs, these projectors were displaced by newer technologies that were lighter, brighter, and easier to use. Still, just like other CRT displays, there was nothing quite like them. And if you find esoteric projector technologies intriguing, we have a feeling you will love the Eidophor.

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Unitree Humanoid Robot Exploit Looks Like A Bad One

Unitree have a number of robotic offerings, and are one of the first manufacturers offering humanoid robotic platforms. It seems they are also the subject of UniPwn, one of the first public exploits of a vulnerability across an entire robotic product line. In this case, the vulnerability allows an attacker not only to utterly compromise a device from within the affected product lines, but infected robots can also infect others within wireless range. This is done via a remote command-injection exploit that involves a robot’s Bluetooth Low Energy (BLE) Wi-Fi configuration service.

Unitree’s flagship G1 humanoid robot platform (one of the many models affected)

While this may be the first public humanoid robot exploit we have seen (it also affects their quadruped models), the lead-up to announcing the details in a post on X is a familiar one. Researchers discover a security vulnerability and attempt responsible disclosure by privately notifying the affected party. Ideally the manufacturer responds, communicates, and fixes the vulnerability so devices are no longer vulnerable by the time details come out. That’s not always how things go. If efforts at responsible disclosure fail and action isn’t taken, a public release can help inform people of a serious issue, and point out workarounds and mitigations to a vulnerability that the manufacturer isn’t addressing.

The biggest security issues involved in this vulnerability (summed up in a total of four CVEs) include:

  • Hardcoded cryptographic keys for encrypting and decrypting BLE control packets (allowing anyone with a key to send valid packets.)
  • Trivial handshake security (consists simply of checking for the string “unitree” as the secret.)
  • Unsanitized user data that gets concatenated into shell commands and passed to system().

The complete attack sequence is a chain of events that leverages the above in order to ultimately send commands which run with root privileges.

We’ve seen a Unitree security glitch before, but it was used to provide an unofficial SDK that opened up expensive features of the Go1 “robot dog” model for free. This one is rather more serious and reportedly affects not just the humanoid models, but also newer quadrupeds such as the Go2 and B2. The whole exploit is comprehensively documented, so get a fresh cup of whatever you’re drinking before sitting down to read through it.

LLM Dialogue In Animal Crossing Actually Works Very Well

In the original Animal Crossing from 2001, players are able to interact with a huge cast of quirky characters, all with different interests and personalities. But after you’ve played the game for awhile, the scripted interactions can become a bit monotonous. Seeing an opportunity to improve the experience, [josh] decided to put a Large Language Model (LLM) in charge of these interactions. Now when the player chats with other characters in the game, the dialogue is a lot more engaging, relevant, and sometimes just plain funny.

How does one go about hooking a modern LLM into a 24-year-old game built for an entirely offline console? [josh]’s clever approach required a lot of poking about, and did a good job of leveraging some of the game’s built-in features for a seamless result.

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Fully-Local AI Agent Runs On Raspberry Pi, With A Little Patience

[Simone]’s AI assistant, dubbed Max Headbox, is a wakeword-triggered local AI agent capable of following instructions and doing simple tasks. It’s an experiment in many ways, but also a great demonstration not only of what is possible with the kinds of open tools and hardware available to a modern hobbyist, but also a reminder of just how far some of these software tools have come in only a few short years.

Max Headbox is not just a local large language model (LLM) running on Pi hardware; the model is able to make tool calls in a loop, chaining them together to complete tasks. This means the system can break down a spoken instruction (for example, “find the weather report for today and email it to me”) into a series of steps to complete, utilizing software tools as needed throughout the process until the task is finished.

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Play Capacitor Cupid With The Matchmaker

Occasionally a design requires capacitors that are much closer to being identical in value to one another than the usual tolerance ranges afford. Precision matching of components from parts on hand might sound like a needle-in-a-haystack problem, but not with [Stephen Woodward]’s Capacitor Matchmaker design.

The larger the output voltage, the greater the mismatch between capacitors A and B.

The Matchmaker is a small circuit intended to be attached to a DVM, with the output voltage indicating whether two capacitors (A and B) are precisely matched in value. If they are not equal, the voltage output indicates the degree of the mismatch as well as which is the larger of the two.

The core of the design is complementary excitation of the two capacitors (the CD4013B dual flip-flop achieves this) which results in a measurable signal if the two capacitors are different; nominally 50 mV per % of mismatch. Output polarity indicates which of the capacitors is the larger one. In the case of the two capacitors being equal, the charges cancel out.

Can’t precision-matched capacitors be purchased? Absolutely, but doing so is not always an option. As [Stephen] points out, selection of such components is limited and they come at an added cost. If one’s design requires extra-tight tolerances, requires capacitor values or types not easily available as precision pairs, or one’s budget simply doesn’t allow for the added cost, then the DIY approach makes a lot more sense.

If you’re going to go down this road, [Stephen] shares an extra time-saving tip: use insulated gloves to handle the capacitors being tested. Heating up a capacitor before testing it — even just from one’s fingers — can have a measurable effect.

[Stephen]’s got a knack for insightful electronic applications. Check out his PWMPot, a simple DIY circuit that can be an awfully good stand-in for a digital potentiometer.

A Closer Look Inside A Robot’s Typewriter-Inspired Mouth

[Ancient] has a video showing off a fascinating piece of work: a lip-syncing robot whose animated electro-mechanical mouth works like an IBM Selectric typewriter. The mouth rapidly flips between different phonetic positions, creating the appearance of moving lips and mouth. This rapid and high-precision movement is the product of a carefully-planned and executed build. When we featured this project before, we wanted to see under the hood. Now we can.

Behind the face is a ball that, when moving quickly enough, gives the impression of animated mouth and lips. The new video gives a closer look at how it works.

[Ancient] dubs the concept Selectramatronics, because its action is reminiscent of the IBM Selectric typewriter. Instead of each key having a letter on a long arm that would swing up and stamp an ink ribbon, the Selectric used a roughly spherical unit – called a typeball – with letters sticking out of it like a spiky ball.

Hitting the ‘A’ key would rapidly turn the typeball so that the ‘A’ faced forward, then satisfyingly smack it into the ink ribbon at great speed. Here’s a look at how that system worked, by way of designing DIY typeballs from scratch. In this robot, the same concept is used to rapidly flip a ball bristling with lip positions.

We first saw this unusual and fascinating design when its creator showed videos of the end result on social media, pronouncing it complete. We’re delighted to see that there’s now an in-depth look at the internals in the form of a new video (the first link in this post, also embedded below just under the page break.)

The new video is wonderfully wordless, preferring to show rather than tell. It goes all the way from introducing the basic concept to showing off the final product, lip-syncing to audio from an embedded Raspberry Pi.

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