Drawing Robot Creates Portraits Using Pen, Paper And Algorithms

October 25, 2021 by Robin Kearey 6 Comments

Although the market for hand-drawn portraits largely collapsed following the invention of photography, there’s something magical about watching an artist create a lifelike image using nothing but a pencil, some paper, and their fine motor skills. Watching a machine do the same is a similarly captivating experience, though often the end result is not so great. Trying to fix this deficiency, [Joris Wegner] and [Felix Fisgus] created the Pankraz Piktograph which seems to do a pretty good job at capturing faces. They were inspired by classic picture-drawing automatons, and made a 21st-century version to be used in museums or at events like trade shows.

The operation of the Piktograph is very simple: you stand in front of the machine, look into the camera and take a selfie. If you like what you see, the robot will then begin to draw your portrait on a piece of paper. It does this using two human-like arms which are made from aluminium and driven by two stepper motors. An ordinary ballpoint pen is held in a spring-loaded carrier, which provides just enough pen-to-paper pressure to reliably draw lines without lifting off or scratching the paper. We can’t help but be impressed with the overall look of the machine: with a sleek, powder-coated aluminium case and a stainless steel stand it’s a work of art by itself.

Inside, the Piktograph is powered by a Raspberry Pi 3, which runs a rather sophisticated algorithm to generate a vector image which doesn’t take too long to draw, but still results in a recognizable image of the subject. The makers’ thesis goes into quite some detail to explain the process, which uses Canny edge detection to create an outline drawing, then fills in the empty bits to create bright and dark areas. A certain amount of noise and wigglyness is added to the lines to give it a more “handmade” feel, and the resulting drawing is divided into continuous lines for efficient drawing by the plotter.

We’ve seen several types of specialized art robots before, capable of drawing portraits with a pen, painting them, or even using an Etch-a-Sketch, but [Joris] and [Felix]’s creation seems to win on speed, workmanship, and the quality of the end result. Video embedded after the break.
Continue reading “Drawing Robot Creates Portraits Using Pen, Paper And Algorithms” →

Mesmerizing Mechanical Seven-Segment Display

October 25, 2021 by Adam Zeloof 14 Comments

Seven-segment displays are ubiquitous. From where I’m writing this, I can see several without even having to swivel my chair. We’re all familiar with their classic visage; slightly italicized numbers that are brought to life by LEDs. There are a boatload of variants available– you can get displays with a decimal point, ones with multiple numbers, and even versions in just about any color you desire, but at the core they’re all basically the same thing- an array of LEDs sitting behind a faceplate. Except for those ones that have some gears inside.

Wait, what?

You read that right– a seven-segment display that contains gears, along with a handful of cams for good measure. Artist [Kango Suzuki] created this stunning all-mechanical seven-segment display that sequentially counts up from zero to nine when a thumbwheel is spun. All of the components are cut from wood and mesh together beautifully, complete with a satisfying click when the display rolls into a new digit, which you can hear in the video at the above link. You may recognize [Kango]’s style from this incredible mechanical clock he made a few years back. Unlike his earlier work, the seven-segment display is tiny, relatively speaking. Maybe we’ll see it integrated into a larger project some day, like a mechanical-digital clock.

We just love when somebody uses intricate mechanisms to artfully emulate some piece of existing tech. This isn’t even the first time we’ve seen a mechanical seven-segment display; [Peter Lehnér] built one back in 2019, and judging by [Kango]’s twitter feed, it appears to have inspired his design. There have even been a few other 3D printed ones over the years, but as far as we know this is the first wooden one– and, in true [Kango] fashion, its beautiful.

Thanks to [J. Peterson] for the tip!

Continue reading “Mesmerizing Mechanical Seven-Segment Display” →

ddrysfeöd circuit art sound and light scultpture

Labyrinthian Circuit Sculpture Evokes Moods With Sound And Light

October 20, 2021 by Ryan Flowers 5 Comments

In a famous letter penned by Victorian era author Oscar Wilde, he wrote:

“Art is useless because its aim is simply to create a mood. It is not meant to instruct, or to influence action in any way. It is superbly sterile, and the note of its pleasure is sterility.”

We can’t help but wonder if [Eirik Brandal] was evoking such Wilde thoughts when he wrote to tell us about ddrysfeöd, an electronic sound and light sculpture which he called “uselessly applied electronics.” Given the mood created by the video below the break, we have to agree that it is indeed quite artful. But if it serves a purpose to inspire and cause wonderment, is it really useless? Let the philosophers philosophize. On to the hack!

[Eirik] was himself inspired by mazes such as those found in children’s activity books and magazines whose goal is to keep a child ~~busy~~ challenged by drawing a solid line from start to finish. With these in mind, [Eirik] constructed ddrysfeöd as an intricate entanglement of electronics, metal, clear and mirrored acrylic, and plated steel, all flung into a three dimensional vortex.

LED’s of red and white oscillate in time with each other. Orchestrating the multimedia symphony is an ESP32, with one core relegated to dealing with the mundane functions of the sculpture while the other waves its electronic wand to keep the ensemble suitably arranged. LED’s are bored into the base, and the acrylic is sanded on the edges to diffuse the supplied light. The electronics run on the usual +5 V, but a +12 V power supply gives volume to the LM380 audio amplifier. We also appreciated that [Eirik] expanded his skills on this project by using Sketchup to plan out the project, even printing the patterns for cutting and drilling the acrylic glass.

If [Eirik]’s build style looks familiar, it may be because you’ve seen it here on Hackaday’s Circuit Sculpture Contest, where some of his work was named Most Beautiful. You can also feast your eyes on a BEAM bot inspired pummer in the shape of a satellite. And remember, if you run across something that presses your buttons, let us know via the Tip Line!

Continue reading “Labyrinthian Circuit Sculpture Evokes Moods With Sound And Light” →

Several shirts side by side, each with a custom design

3D Print A Custom T-Shirt Design, Step-by-Step

October 15, 2021 by Donald Papp 14 Comments

Want to make a t-shirt with a custom design printed on it? It’s possible to use a 3D printer, and Prusa Research have a well-documented blog post and video detailing two different ways to use 3D printing to create colorful t-shirt designs. One method uses a thin 3D print as an iron-on, the other prints directly onto the fabric. It turns out that a very thin PLA print makes a dandy iron-on that can survive a few washes before peeling, but printing flexible filament directly onto the fabric — while more complicated — yields a much more permanent result. Not sure how to turn a graphic into a 3D printable model in the first place? No problem, they cover that as well.

Making an iron-on is fairly straightforward, and the method can be adapted to just about any printer type. One simply secures a sheet of baking paper (better known as parchment paper in North America) to the print bed with some binder clips, then applies glue stick so that the print can adhere. A one- or two-layer thick 3D print will stick to the sheet, which can then be laid print-side down onto a t-shirt and transferred to the fabric by ironing it at maximum temperature. PLA seems to work best for iron-ons, as it preserves details better. The results look good, and the method is fairly simple.

Direct printing to the fabric with flexible filament can yield much better (and more permanent) results, but the process is more involved and requires 3D printing a raised bed adapter for a Prusa printer, and fiddling quite a few print settings. But the results speak for themselves: printed designs look sharp and won’t come loose even after multiple washings. So be certain to have a few old shirts around for practice, because mistakes can’t be undone.

A very thin 3D print makes a decent iron-on that survives a few washes.

A 3D-printed bed adapter enables direct printing onto fabric for better results.

That 3D printers can be used to embed designs directly onto fabric is something many have known for years, but it’s always nice to see a process not just demonstrated as a concept, but documented as a step-by-step workflow. A video demonstration of everything, from turning a graphic into a 3D model to printing on a t-shirt with both methods is all in the short video embedded below, so give it a watch.

Continue reading “3D Print A Custom T-Shirt Design, Step-by-Step” →

LED Matrix Hourglass Knows Which Way Is Up

October 8, 2021 by Donald Papp 6 Comments

[Fearless Night]’s slick dual hourglass doesn’t just simulate sand with LEDs, it also emulates the effects of gravity on those simulated particles and offers a few different mode options.

The unit uses an Arduino (with ATMEGA328P) and an MPU-6050 accelerometer breakout board to sense orientation and movement, and the rest is just a matter of software. Both the Arduino and the MPU-6050 board are readily available and not particularly expensive, and the LED matrix displays are just 8×8 arrays of red/green LEDs, each driven by a HT16K33 LED controller IC.

The enclosure and stand are both 3D-printed, and a PCB not only mounts the components but also serves as a top cover, with the silkscreen layer of the PCB making for some handy labels. It’s a clever way to make the PCB pull double-duty, which is a technique [Fearless Night] also used on their earlier optical theremin design.

Those looking to make one of their own will find all the design files and source code handily available from the project page. It might not be able to tell time in the classical sense, but seeing the hourglass displays react to the device’s orientation is a really neat effect.

Automate Your Graffiti With The Graffomat!

September 30, 2021 by Jim Heaney 30 Comments

In Banksy’s book, Wall and Piece, there is a very interesting quote; “Imagine a city where graffiti wasn’t illegal, a city where everybody could draw whatever they liked…”. This sounds like it would be a very exciting city to live in, except for those of us who do not have an artistic bone in their body. Luckily, [Niklas Roy] has come up with the solution to this problem; the Graffomat, a spray can plotter.

The Graffomat is, in its creator’s own words, a “quick and dirty graffiti plotter.” It is constructed primarily from wood and driven by recycled cordless drills that pulls string pulleys to move the gantry. The Arduino Nano at the heart of the Graffomat can be controlled by sending coordinates over serial. This allows for the connection of an SD card reader to drip-feed the machine, or a computer to enable real-time local or over-the-internet control.

We are especially impressed with how [Niklas] handled positional tracking. The cordless drills were certainly not repeatable like a stepper motor, as to allow for open-loop control. Therefore, the position of the gantry and head needed to be actively tracked. To achieve this, the axes are covered with black and white striped encoder strips, that is then read by a pair of phototransistors as the machine moves along. These can then be paired with the homing switches in the top left corner to determine absolute position.

Graffomat is not the first automated graffiti machine we’ve covered. Read here about the robot that painted murals by climbing smokestacks in Estonia.

Continue reading “Automate Your Graffiti With The Graffomat!” →

A man watching money being shredded in a picture frame

Banksy-Like Stock Tracker Shreds Your Money When The Market’s Down

September 20, 2021 by Robin Kearey 14 Comments

For anyone playing the stock market, and perhaps even more so for those investing in cryptocurrencies, watching the value of your portfolio go up and down can be a stressful experience. If you’d like to have a real-time display of your investments that adds even more stress, [Luis Marx] has got you covered. His latest project is a plexiglass case (video in German) that fills up with banknotes when your portfolio is up, and shreds those same notes when it’s down.

Inspired by an infamous Banksy artwork, [Luis] began by building a wood-and-plexiglass display case suitable for hanging on the wall in his office. He then installed a small paper shredder, modified with a servo so that it could be operated by an Arduino. Unable to find an off-the-shelf banknote dispenser, he designed and 3D-printed one, consisting of a spring-loaded tray and a motor-driven wheel.

The project also includes a Raspberry Pi, programmed to fetch market data from online sources and calculate the net profit or loss of [Luis]’s portfolio. The resulting system is a rather disturbing visualization of the ups and downs of the market: having to sweep strips of green paper off your floor adds insult to the pain of losing money.

If you want a less painful way to keep track of your investments, try this Rocketship. For those interested in traditional stock tickers, this ESP32 based one might be more to your liking.

Continue reading “Banksy-Like Stock Tracker Shreds Your Money When The Market’s Down” →