Robotic Acrobot Aces The Moves

[Daniel Simu] is a performance artist, among many other things, and does acrobatic shows, quite often with a partner “flyer”. Training for his acts gets interrupted if his flyer partner is not available due to travel, injury or other reasons. This prompted him to build Acrobotics — a robotic assistant to make sure he can continue training uninterrupted.

He has some electronics and coding chops, but had to teach himself CAD so that he could do all of the design, assembly and programming himself. Acrobotics was developed as part of a Summer Sessions residency at V2_ (Lab for the Unstable Media) at Rotterdam in 2022.

The design is built around a mannequin body and things are quite simple at the moment. There are only two rotational joints for the arms at the shoulder, and no other articulations. Two car wiper motors rotate the two arms 360 deg in either direction. Continuous rotation potentiometers attached to the motors provide position feedback.

An ESP32 controls the whole thing, and the motors get juice via a pair of BTS7960 motor drivers. All of this is housed in a cage built from 15 mm aluminium extrusion and embedded in the torso of the mannequin. [Daniel] doesn’t enlighten us how the motor movements are synchronized with the music, but we do see a trailing cable attached to the mannequin. It’s likely the cable could be for power delivery, as well as some form of data or timing signals.

He’s working on the next version of the prototype, so we hope to see improved performances soon. There’s definitely scope for adding a suite of sensors – an IMU would help a lot to determine spatial orientation, maybe some ultrasonic sensors, or a LiDAR for object detection or mapping, or additional articulated joints at the elbows and wrists. We gotta love “feature creep”, right ?

Check out the two videos after the break – in the first one, he does an overview of the Acrobotics, and the second one is the actual performance that he did. Robot or not, it’s quite an amazing project and performance.
CAVEAT : We know calling this a “robot” is stretching the definition, by a lot, but we’re going to let it slip through.

Continue reading “Robotic Acrobot Aces The Moves”

Chataigne: An Open-Source Swiss Army Knife

[Ben Kuper] is a developer with a history of working on art installations, and had hit upon a common problem often cited by artists. When creating installations involving light, sound, and motion, they often spend too much time on the nuts and bolts of electronics, programming, and so on. Such matters are a huge time sink with a steep learning curve and oftentimes just a plain distraction from the actual artistic intent they’re trying to focus upon. [Ben] has been working for a few years on a software tool, Chataigne which is designed as the glue between various software tools and hardware interfaces, enabling complex control of the application using simple building blocks. Continue reading “Chataigne: An Open-Source Swiss Army Knife”

Interview: Stuart Semple On Pantone, Freetone, Colour, And Open Source

We recently covered the removal of Pantone colour support from the Adobe cloud products, with the two companies now expecting artists and designers to pay an extra subscription for a Pantone plugin or face losing their Pantone-coloured work to a sea of black blocks. Our coverage focused on our community, and on how the absurdity of a commercial entity attempting to assert ownership over colours would have no effect on us with our triple-byte RGB values.

Interview With An Artist And Pigment Activist

Freetone, 1280 liberated colours, Stuart Semple
The palette that could start a revolution.

It’s fair to say though that in our focus on hardware hackers and open source enthusiasts, we missed its effect on artists and designers. To rectify this omission we needed to step outside our field and talk to an artist, and in that context there’s an obvious person to interview.

Stuart Semple is probably one of the more famous contemporary British artists, but in relation to this story it’s his activism over the issue of colours and intellectual property that makes him an authority. He’s drawn attention to the issue by releasing his own art materials in colours that directly challenge those which companies have tried to claim for themselves, and is perhaps best known in our community for challenging Anish Kapoor’s exclusive licence for VantaBlack, the so-called “world’s blackest pigment”.

Most recently in response to the Adobe/Pantone controversy he’s released Freetone, a free plugin for the Adobe suite that in the words from its web page contains “1280 Liberated colours are extremely Pantoneish and reminiscent of those found in the most iconic colour book of all time. In fact it’s been argued that they are indistinguishable from those behind the Adobe paywall”. I had a phone conversation with him, in which he explained why Freetone had come into being.

Hackaday I understand Pantone is something used by designers, so I’ve worked for companies in the past where the designer would specify a Pantone index and it would appear on the screen, on the printed box, and on everything else identically. But why why do you as an artist use Pantone?

A rack of test tubes of blood-red paint
Art, activism, and a very red pigment.

Stuart Well, I use it in lots of ways. So I make a lot of screen prints as part of my art. So you know, if I’m working with a screen printer, I want to know that the print that they make of my work is the colour that I want it to be, so Pantone’s really useful for me for that.

But also, even with within the paints, so I just did a thing where I made some paints, which actually uses the blood of gay men. It was really important to me that the colour of the paint matched the colour of actual blood. So I was working with a lot of people, we’ve been collaborating, and I was working with some friends in New York on it, and we needed a common language.

The red I was talking about was the red they were talking about, and Pantone is super useful for that. In fact, it’s the go-to for that. I just did a record cover for Placebo, the band, that was produced for me by someone that prints, so I had to tell them what spot colours I wanted. So I had to tell them Pantone references, it’s the language they understand.

Hackaday So my next question relates to Freetone. Obviously, as as you’ve distributed it, it’s a Adobe plugin. How does it solve the problem? Because obviously, I can specify a Freetone colour, and anybody else with Freetone can tell yes, that’s that colour. But how do I then go to a printer who buys his inks with Pantone specifications and map one to the other?

An open Pantone swatch book in a fan
The Pantone swatch book which you’ll see in the hands of artists and designers everywhere. Céréales Killer CC BY-SA 3.0.

Stuart How it works is, if you download Freetone, you’ll find colours in there, and one of them will be called Sempletone 648C. Well, it’s exactly the same as Pantone 648C. If you do your work on the screen, use the Freetones, and then when you send it to the printer, it’s actually blatantly obvious to anyone that 648C is clearly apparent. If you’ve got the Pantone fan book and you look at the colours, it’s the same. 846C in mine is the same as 846C in the fan, in the Pantone book. I’d like to see them try and argue that they own it, but I don’t think they do in the name or the Pantone trademark, but these are Sempletones with a number. So I think it’s gonna be hard.

Hackaday My next question is probably getting more into the technology of it all. Do you think it will be possible to replace Pantone’s service completely? So if you took every Sempletone colour and threw it at a spectrometer and published the spectrum, would you then be able to say to an ink manufacturer or similar, here are the full technical details rather than just a colour, and does your paint correspond to this spectrum? I’m curious how far you could push open source in this line.

PySpectrometer version 2, showing mini spectroscope, 4 inch display and hand for scale
The PySpectrometer project, something for anyone with an interest in colour.

Stuart That’s really cool. I love it. Like, if you could just give them that spectral data, and if they’ve got a spectrometer they could measure it a their end. But there’s nothing that advanced at the moment, a lot of action is done by eye still. My answer is, I don’t see why not if there was a cool enough device. I don’t know if the spectrometer would be good enough to match it. I don’t see why not, I don’t see why you couldn’t publish the data. But it would have to be the whole spectral information and not just like an RGB value.

(At this point the interview digressed for a moment into a discussion of open-source spectrometers such as the Raspberry Pi project we featured recently, as Stuart’s lament was that a spectrometer can be an extremely expensive instrument. It isn’t the job of an interviewer to lead their interviewee so we’re skipping this part of the transcript, however I think we can all look forward to whatever uses Stuart makes of an affordable spectrometer. We’ll pick up the interview at the next question.)

Photoshop Pantone warning popup.
This widely shared screenshot represents the destruction of past work.

Hackaday One of the real problems with the whole Adobe suite, and this has happened in world as well with for instance the Autodesk CAD packages, is that they have gone into the cloud and become software as a subscription. So I understand completely, the frustration of artists at suddenly being told they have to pay an extra subscription to keep their Pantone support, and I’m particularly shocked to find that Photoshop isn’t just displaying black pixels over Pantone colours, I’m told it’s wiping out the Pantone information on saving. Do you think that anything in the open source software ecosystem comes close to replacing proprietary products like the Adobe suite for you as an artist?

Stuart Yes, 100%, there’s loads of stuff. I think open source is just the answer, I believe in freedom. And freedom means freedom to express yourself and freedom to own the thing and tweet the thing and change the thing and all the rest of it. So yeah, 100%. I think there’s actually better things than Photoshop, the problem we’ve got is that Adobe have the industry stranglehold. And if you want to work with someone, you have to be talking that language. And that’s still the problem. It’s like an operating system, but it’s got the monopoly.

So there are other things, for instance, on a Mac, there’s something called Pixelmator, which is as good as Photoshop in my opinion, I use it every day. It’s not free, but you buy it once, and that’s it, free updates. Like software used to be. And there are other things, like GIMP is amazing. It’s awesome, but it doesn’t really replace Photoshop.

A screenshot of GIMP
We all like using GIMP, perhaps other people could learn to love it too. (gimp.org)

Hackaday Here at Hackaday we can make noises about how wouldn’t it be great if the developers of GIMP or other software could stick Freetone into their products, because they don’t have Pantone as it’s licensed?

Stuart Yeah, that’d be a dream, wouldn’t it? I mean, why not? I made it for everybody. As far as I’m concerned, it’s out there, use it, change it. incorporate it, the more people the better, I think.

A lot of people use GIMP, and it’s good. Really good open source stuff that always has been. We know the future is in the open source stuff, proprietary stuff just won’t last, it’s just not adaptable. It’s putting greed and profits above the user, it can’t work. There’s no freedom in it.

Hackaday To me the most egregious thing is that as I understand it they will delete the Pantone information from your PSD.  This really shocked me.

Stuart They’re literally holding it hostage. It’s like 20 quid, or delete from your work, which is, wow. They’re not giving me anything, anyway. I’m renting the software, paying to use the software every month, it’s not free. And the licence fee is a lot. We’re already spending hundreds and hundreds a year on this software, probably about 800 quid a year. Another 20 quid, just to pen the work we make before. I mean, it’s our work! It’s pure corporate greed, isn’t it.

Hackaday Thank you very much for the interview.

As we wrapped up, I asked him about his Black 3.0 pigment, produced as a reaction to VantaBlack and Anish Kapoor. I was curious whether it might have a specially good infra-red response for headsinks or solar collectors, but sadly he informed me that it’s primarily a visual colour for artists. It’s very cool stuff, incredibly black, and I really want to get some to play with, but probably no better than a rattle can for heat purposes. Never mind, an engineer’s curiosity satisfied.

What’s Next, For Both Artists And Engineers?

Swatchbooker screenshot
Could SwatchBooker hold the answer?

Following the interview, it’s worth looking at the Freetone project from our side of the table as well as his. If we as a community would like to ensure that colours do not become ever more proprietary, then it is probably on us to ensure that where appropriate it is supported within our sphere. GIMP support for instance would at a stroke make open source software an easier choice for millions of artists and designers, and could I think be done relatively easily through its existing palette support. There’s SwatchBooker which appears to perform the necessary interchange, and I found the ASE2GIMP project which imports Adobe palettes into GIMP, but sadly I couldn’t make it work here. If GIMP shipped with a Freetone palette built-in, would that be too much of a development task to contemplate?

From Stuart’s side, having sat down and played with Freetone, if there’s one thing I could ask him it would be to release it as more than just an Adobe plugin, and to give it an open source licence. As it stands it’s a binary available for no charge through his web shop, I think that releasing it as a straightforward list, perhaps even as simple as a CSV file, would make it so much more accessible to developers. And coupled with an open source licence that allowed them to include it within their software, I think it would be unstopable. We’re not open source licence nerds here at Hackaday, but I’m guessing something that does the same for a palette as a library licence such as the LGPL does for libraries would be appropriate.

In our world we’re wrapped up in electronics and code, and it’s sometimes easy to forget that the work we do reaches way beyond our workbenches. If you’ve spent enough time in a hackerspace you’ll know that art and engineering are almost the two sides of the same coin, so it’s pleasing to find such a moment of crossover. Let’s hope Freetone support can find its way into the open source movement, and together we can keep the tentacles of yet another IP land grab at bay.

a kinetic bar framework mounted on a wooden base made of 3d printed bars of alternative black and grey color, each joined with m3 bolts and nuts

Kinetic Cyclic Scissors

[Henry Segerman] and [Kyle VanDeventer] merge math and mechanics to create a kinetic cyclic scissors sculpture out of 3D printed bars adjoined together with M3 bolts and nuts.

a kinetic bar framework with 3d printed bars of alternative black and grey color, each joined with m3 bolts and nuts being held by a person at two points with a quadrilateral tiling overlay

The kinetic sculpture can be thought of as a part of an infinite tiling of self similar quadrilaterals in the plane. The tiling of the plane by these self similar quadrilaterals can be realized as a framework by joining the diagonal points of each quadrilateral with bars. The basic question [Henry] and [Kyle] wanted to answer was under what conditions can the realized bar framework of a subsection of the tiling be made to move. Surprisingly, when the quadrilateral is a parallelogram, like in a scissor lift, or “cyclic”, when the endpoints lie on a circle, the bar framework can move. Tweaking the ratios of the middle lengths in a cyclic configuration leads to different types of rotational symmetry that can be achieved as the structure folds in on itself.

[Henry] and [Kyle] go into more detail in their Bridges Conference paper, with derivations and further discussions about the symmetry induced by adjusting the constraints. The details are light on the actual kinetic sculpture featured in the video but the bar framework was chosen to have a mirror type of symmetry with a motor attached to one of the central, lower bars to drive the movement of the sculpture.

The bar framework is available for download for anyone wanting to 3D print or laser cut their own. Bar frameworks are useful ideas and we’ve seen them used in art sculptures to strandbeests, so it’s great to see further explorations in this space.

Video after the break!

Continue reading “Kinetic Cyclic Scissors”

How The Art-Generating AI Of Stable Diffusion Works

[Jay Alammar] has put up an illustrated guide to how Stable Diffusion works, and the principles in it are perfectly applicable to understanding how similar systems like OpenAI’s Dall-E or Google’s Imagen work under the hood as well. These systems are probably best known for their amazing ability to turn text prompts (e.g. “paradise cosmic beach”) into a matching image. Sometimes. Well, usually, anyway.

‘System’ is an apt term, because Stable Diffusion (and similar systems) are actually made up of many separate components working together to make the magic happen. [Jay]’s illustrated guide really shines here, because it starts at a very high level with only three components (each with their own neural network) and drills down as needed to explain what’s going on at a deeper level, and how it fits into the whole.

Spot any similar shapes and contours between the image and the noise that preceded it? That’s because the image is a result of removing noise from a random visual mess, not building it up from scratch like a human artist would do.

It may surprise some to discover that the image creation part doesn’t work the way a human does. That is to say, it doesn’t begin with a blank canvas and build an image bit by bit from the ground up. It begins with a seed: a bunch of random noise. Noise gets subtracted in a series of steps that leave the result looking less like noise and more like an aesthetically pleasing and (ideally) coherent image. Combine that with the ability to guide noise removal in a way that favors conforming to a text prompt, and one has the bones of a text-to-image generator. There’s a lot more to it of course, and [Jay] goes into considerable detail for those who are interested.

If you’re unfamiliar with Stable Diffusion or art-creating AI in general, it’s one of those fields that is changing so fast that it sometimes feels impossible to keep up. Luckily, our own Matthew Carlson explains all about what it is, and why it matters.

Stable Diffusion can be run locally. There is a fantastic open-source web UI, so there’s no better time to get up to speed and start experimenting!

In A Way, 3D Scanning Is Over A Century Old

In France during the mid-to-late 1800s, one could go into François Willème’s studio, sit for a photo session consisting of 24 cameras arranged in a circle around the subject, and in a matter of days obtain a photosculpture. A photosculpture was essentially a sculpture representing, with a high degree of exactitude, the photographed subject. The kicker was that it was both much faster and far cheaper than traditional sculpting, and the process was remarkably similar in principle to 3D scanning. Not bad for well over a century ago.

This article takes a look at François’ method for using the technology and materials of the time to create 3D reproductions of photographed subjects. The article draws a connection between photosculpture and 3D printing, but we think the commonality with 3D scanning is much clearer.

Continue reading “In A Way, 3D Scanning Is Over A Century Old”

Rib Cage Lamp Kicks It Up A Notch With Party Mode

We think [Michelle]’s sound-reactive rib cage lamp turned out great, and the photos and details around how it was made are equally fantastic. The lamp is made of carved and waxed wood, and inside is a bundle of LED lighting capable of a variety of different color palettes and patterns, including the ability to react to sound. Every rib cage should have a party mode, after all.

The LED strip is fashioned into an atom-like structure.

Turns out that designing good rib cage pieces is a bigger challenge than one might think. [Michelle]’s method was to use an anatomical 3D model as reference, tracing each piece so that it could be cut from a flat sheet of wood.

The resulting flat pieces then get assembled into a stack, with each rib pointed downward at a roughly 20 degree angle. This process is a neat hack in itself: instead of drilling holes all at exactly the same angle, [Michelle] simply made the holes twice the diameter of the steel rod they stack on. The result? The pieces angle downward on their own.

The LED lighting is itself a nice piece of work. The basic structure comes from soldered solid-core wire. The RGB LED strip gets wound around that, then reinforced with garden wire. The result is an atomic-looking structure that sits inside the rib cage. An ESP32 development board drives everything with the FastLED library.

Code for everything, including the sound-reactive worky bits, which rely on an INMP441 I2C microphone module is all available on GitHub. And if you want to make your own sound-reactive art, make sure to check out these arms as well.

Want to see the rib cage in action? A short demo video is embedded below that demonstrates the sound reactivity. Equally applicable to either party or relaxation modes, we think.

Continue reading “Rib Cage Lamp Kicks It Up A Notch With Party Mode”