Talking Robot Uses Typewriter Tech For Mouth

August 8, 2025 by Lewin Day 15 Comments

Many decades ago, IBM engineers developed the typeball. This semi-spherical hunk of metal would become the heart of the Selectric typewriter line. [James Brown] has now leveraged that very concept to create a pivoting mouth mechanism for a robot that appears to talk.

What you’re looking at is a plastic ball with lots of different mouth shapes on it. By pivoting the ball to different angles inside the head of a robot, it’s possible to display different mouth shapes on the face. By swapping mouth shapes rapidly in concert with recorded speech, it’s possible to make the robot appear to be speaking. We don’t get a great look at the mechanism that operates the ball, but Selectric typeball operation is well documented elsewhere if you seek to recreate the idea yourself.

The real benefit of this mechanism is speed. It might not look as fluid as some robots with manually-articulated flexible mouths, but the rapid mouth transitions really help sell the effect because they match the pace of speech. [James] demonstrated the finished product on Mastodon, and it looks great in action.

This isn’t the first time we’ve featured [James Brown]’s work. You may recall he got DOOM running on a tiny LEGO brick a few years back.

Thanks to [J. Peterson] for the tip!

Hackaday Links: March 19, 2023

March 19, 2023 by Dan Maloney 11 Comments

We get results! Well, sort of. You may recall that in this space last week we discussed Ford’s plans to exclude AM reception on the infotainment systems of certain of their cars starting in 2024. We decried the decision, not for the loss of the sweet, sweet content that AM stations tend to carry — although we always enjoyed “Traffic on the 8s” back in our dismal days of daily commuting — but rather as a safety concern, because AM radio can reach almost the entire US population with emergency information using just 75 stations. To our way of thinking, this makes AM radio critical infrastructure, and eliminating it from motor vehicles is likely to have unintended consequences. Now it seems like there’s some agreement with that position, as former administrators of FEMA (Federal Emergency Management Administration; and no, not FEDRA) have gotten together to warn about the dangers of deleting AM from cars. Manufacturers seem to be leaning into the excuse that EVs emit a lot of radio frequency interference, rendering static-sensitive AM receivers less useful than other, ~~more profitable~~ less susceptible modes, like digital satellite radio. That seems like a red herring to us, but then again, the most advanced infotainment option in any car we’ve ever owned is a CD player, so it’s hard for us to judge.

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Realistic Animatronic Eyes Are An Easy DIY Build

February 15, 2023 by Lewin Day 12 Comments

It’s not Halloween yet, but if you’re planning a technically-complicated costume, it might serve you well to start building now. To that end, here’s a guide from [Ikkalebob] on how to produce a compact animatronic eye mechanism.

The eye is inspired by mechanisms used in professional animatronics. However, that doesn’t mean it’s hard to build. Complex machining is done away with in favor of readily reproducible 3D-printed components. The eyes are able to look in different directions and can move realistically, and the build includes working eyelids that have a great blinking action to them that feels very natural. An Arduino Uno is charged with running the eyes, paired with a bunch of hobby servos and an Adafruit PCA9685 servo driver. A hefty 5V, 4 amp power supply is on hand to deliver enough juice so the servos move smoothly without stuttering.

It’s the kind of thing that’s perfect for your spooky familiar, or installing eyes in the back of your head. It would be perfect to hide behind a window or in the bushes, too. Video after the break.

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Teardown: How Many Teddy Ruxpins Does It Take To Start A Coven?

July 21, 2022 by Kristina Panos 35 Comments

Well, I did it. I conquered my childhood fear of talking bears and brought a vintage Teddy Ruxpin animatronic stuffed bear into my home. There were and still are plenty of his brethren both young and old to choose from on the auction sites, and when I saw this particularly carefree barefoot Teddy in his Hawaiian shirt and no pants, I was almost totally disarmed. Plus, the description promised a semi-working unit with a distorted voice, and who among us could resist a specimen in such condition? Maybe the tape deck motor is going out, or it just needs a new belt. Maybe the tape itself messed up, and Teddy is fine. I had to find out.

But let me back up a bit. If you don’t know what I’m talking about, Teddy Ruxpin was a revolutionary toy that dropped in 1985. It’s a talking teddy bear that reads stories aloud, all the while moving his eyes and mouth to the sounds. Along with Teddy came special cassette tapes, corresponding story books, and outfits. I wanted one when I was a kid, but was also kind of scared of them. Since they were so expensive — about $250 inflation-adjusted for the bear and a single tape / book / outfit, plus another $15 for four D cells — I never did get one in my youth.

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Small Scale Mad Max: Danny Huynh’s Dystopian Animatronics

September 6, 2021 by Danie Conradie 11 Comments

The hacker spirit is always alive and well in post-apocalyptic fiction, as characters throw together contraptions from whatever junk they can find. While these might not always be practical or possible in reality, their primary purpose is usually to look the part. This is definitely the case for [Danny Huynh]’s post-apocalyptic animatronic creations, which look like they can slot straight into Mad Max or Fallout.

[Danny] is an avid RC enthusiast, so many of the models are highly customized off-the-shelf RC cars. However, it’s the lifelike moving characters in these models that really catch the eye. Their hands and feet move with the steering and throttle, and in the motorcycle builds they will often lean with the turns. Other notable builds include a hexapedal taxi and a couple of animatronic bands.

All the vehicle builds are electric, but it looks like [Danny] often includes an audio module to simulate a roaring engine. He makes extensive use of servos and linkages for character movement, with wiring and electronics carefully hidden by paint or bodywork.

With all the CGI technology available today, great animatronic builds like an eerily lifelike heart, or a talking Nikola Tesla are all the more impressive to see.

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Animatronic Puppetry Controller Skips Joystick Or Keyboard

September 4, 2021 by Danie Conradie 2 Comments

One of the major challenges of animatronics is creating natural looking motion. You can build something with an actuator for every possible degree of freedom, but it will still be disappointing if you are unable to control it to smoothly play the part. [Mr. Volt] has developed a passion for animatronic projects, but found programming them tedious, and manual control with keyboard or controller difficult to do right. As an alternative, he is building Waldo, an electronic puppetry controller.

The Waldo rig is being developed in conjunction with [Mr. Volt]’s build of Wheatley, the talkative ball-shaped robot from the Portal 2 game. The puppetry rig consists of a series of rings for [Mr Volt]’s hand, with the position of each being read by angle sensors. This allows him to control Wheatley’s orientation of the body and eyeball, eyelids, and handles. Wheatley and Waldo both still need a few refinements, but we look forward to seeing the finished project in action.

The Portal games have inspired several featured projects, including GLaDOS, the turrets, and of course more Wheatly builds.

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Smooth Servo Motion For Lifelike Animatronics

September 3, 2021 by Danie Conradie 10 Comments

Building an animatronic robot is one thing, but animating it in a lifelike fashion is a completely different challenge. Hobby servos are cheap and popular for animatronics, but just letting it move at max speed isn’t particularly lifelike. In the video after the break, [James Bruton] demonstrates how to achieve natural motion with a simple animatronic head and a few extra lines of code.

Very little natural body movement happens at a constant speed, it’s always accelerating or decelerating. When we move our heads to look at something around us, our neck muscles accelerate our head sharply in the chosen direction and then slows down gradually as it reaches its endpoint. To do this in Arduino/C code, a new intermediate position for the servo is specified for each main loop until it reaches the final position. The intermediate value is the sum of 95% of the current position, and 5% of the target position. This gives the effect of the natural motion described above. The ratios can be changed to suit the desired speed.

The delay function is usually one of the first timing mechanisms that new Arduino programmers learn about, but it’s not suited for this application, especially when you’re controlling multiple servos simultaneously. Instead, the millis function is used to keep track of the system clock in the main loop, which fires the position update commands at the specified intervals. Adafruit wrote an excellent tutorial on this method of multitasking, which [James] based his code on. Of course, this should be old news to anyone who has been doing embedded programming for a while, but it’s an excellent introduction for newcomers.

Like most of [James]’s projects, all the code and CAD files are open source and available on GitHub. His projects make regular appearances here on Hackaday, like his mono-wheel balancing robot and mechanically multiplexed flip-dot display.

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