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” →

Building A Multi-Ton Power Loader For Fun

October 6, 2021 by Danie Conradie 18 Comments

Exoskeletons, power suits, and iron suits in science fiction have served as the inspiration for many engineers and engineering projects over the years. This is certainly the case at [Hacksmith Industries], where Hackaday alum [James Hobson] has been building a massive mechanical exoskeleton since January 2019, inspired by the P-5000 Power Loader from the Alien movies. (Video, embedded below.)

Unlike the movie version, the [Hacksmith] power loader is not bipedal but built on top of the chassis of a small tracked skid-steer loader. Its existing hydraulic power unit also feeds all the upper body hydraulic cylinders. The upper body maintains the basic look of the movie version and was built from plasma-cut steel sections that fit together with a tab and slot system before being welded. Each arm has five degrees of freedom, controlled by proportional hydraulic valves. The power loader is controlled by an industrial grade control system based on the Raspberry Pi, running ROS.

Every single actuator is capable of applying enough force to kill, so safety is an important consideration in the design. It has emergency stop buttons mounted in several locations, including on a wireless remote. The ROS controller monitors the position of every cylinder using string potentiometers for closed-loop control, and to trigger the emergency stop if an actuator goes out of bounds. The power loader can be controlled by the onboard pilot using a pair of simulator flight controller joysticks, or remotely using a PS4 controller.

[Hacksmith Industries] is clear about the fact that they are building multi-ton power loaded for fun and entertainment, not because it’s necessarily practical or a commercially viable product. However, other exoskeletons have proven that they are a viable solution for reducing fatigue and risk of injury for industrial workers, and carrying heavy loads in rough terrain.

Continue reading “Building A Multi-Ton Power Loader For Fun” →

An image of Kitten Mittens and its 3lb counterpart

Why Make A Combat Robot That Walks?

October 1, 2021 by Jim Heaney 13 Comments

If you watch it on TV or see clips on YouTube, you’ll notice that most combat robots have wheels, which would make sense. They are simple, work well, and if designed right they can take a bit of a beating. So why did [Luke] design his 12-pound bot with no wheels, or any locomotion system for that matter? You can find out more about this peculiar bot in his build report with more than 130 images.

[Luke’s] bot, called Kitten Mittens, is a gyro walker combat robot. This means that instead of traditional tank treads or wheels to move about, [Luke] navigates by angling his bot’s weapon and using the angular momentum to lift up one side of the bot to “walk” forward. Watch the video after the break to see it in action. While this does leave Kitten Mittens much slower and less agile than competitors, it gives one massive leg up; weight. Kitten Mittens fights in the 12-pound combat robotics weight class, but most leagues have weight bonuses for bots that have no wheels or use otherwise nontraditional locomotion. Where [Luke] competes, the Norwalk Havoc Robot League, this means that his bot can be up to 6 pounds heavier than the other competitors!

A 3D-printed prototype of Kitten Mittens' weapon — A printed prototype of the weapon, showing off the integrated hub motor.

So how did [Luke] take advantage of that extra 6 pounds? The biggest thing was the weapon. It is made of 3/4-inch S7 tool steel and has a custom hub motor integrated into the center, bringing its rotating weight to 5.5 pounds. In addition to thickness, the added weight allowance permitted a larger spinning diameter so that Kitten Mittens could hit opponents before they hit him.

[Luke] is not new to the world of combat robotics, and knew it would take more than just a big weapon to win. Part of the extra weight budget was also used to beef up his armor and internal structure of the bot, so that hits from opponents would just bounce him around the cage harmlessly. This even included custom bent titanium guards surrounding the weapon, to help in self-righting.

When it first debuted in February of 2021, Kitten Mittens was a smashing success! It went 4-0 in the 12lb weight class at NHRL, winning the $1,000 prize and earning its spots in the annual finals, where [Luke] will compete against other finalists from the rest of the season for a chance to win the $12,000 first-place prize.

Bots that walk, shuffle, or crawl are becoming more of a trend lately in all weight classes. Even Overhaul, a 250-pound bot, has been given a new set of feet to shuffle around on. You can read more about this interesting concept here.

Continue reading “Why Make A Combat Robot That Walks?” →

Project HERMITS Robots Mimic Crabs With Mechanical Shells

September 27, 2021 by Lewin Day 1 Comment

Hermit crabs are famous for being small critters that, from time to time throughout their lives, abandon one shell carried on their back to pick up a new one. Project HERMITS by [Ken Nakagaki] is inspired by this very concept, and involves table-top robots that dock with a variety of modules with different mechanical mechanisms.

As shown in the project video, the small robots augment themselves by interfacing with attachments referred to as “mechanical shells.” They variously allow the robot to move differently or interact in a new way with the world.

One shell allows the robot to activate a small fan, while another lets it rotate arrows in various directions. others let robots work together to actuate a bigger mechanical assembly like a gripper or a haptic feedback joystick.

A particularly cute example is the “lift shell” which allows one little robot give another one a boost in height. Another series of shells allows the robots to play the role of various characters in a performance of Alice in Wonderland.

The technology is all built around Sony’s tiny two-wheeled toio robots, but adds a vertical actuator to the platform that lets the robots actively dock with a variety of shell designs. It’s an involved hack, but key to the whole enterprise. The individual bots are all controlled by Raspberry Pis communicating over Bluetooth.

We always love to see cute robots working together. Video after the break.

Continue reading “Project HERMITS Robots Mimic Crabs With Mechanical Shells” →

Self Balancing Robot Needs A Little Work

September 20, 2021 by Al Williams 6 Comments

A self-balancing robot isn’t a new idea, but we liked the aesthetics of [Maker ATOM’s] build. The use of a breadboard and a printed bracket looks good, as you can see in the video, below.

Like most first-time projects, though, there were some lessons learned. The power supply needs a little work and the range of balance compliance didn’t meet expectations. But those problems are soluble and, as usual, you often learn more from working through issues like these.

Continue reading “Self Balancing Robot Needs A Little Work” →

Line Following Robot Uses PID For Speed

September 18, 2021 by Al Williams 19 Comments

While a line-following robot may not be the newest project idea in the book, this one from [Edison Science] is a clean build using modern components and gets a good speed thanks to PID control feedback instead of the more traditional bang-bang control you see in low-end robots.

Of course, PIDs need tuning and that seems to be the weak link — you’ll have to experiment with the settings. The sensors also require calibration, but we bet both of those issues could be fixed pretty easily.

Continue reading “Line Following Robot Uses PID For Speed” →

Grappling Hook Robot Swings Like Spiderman

August 28, 2021 by Al Williams 3 Comments

We’ll admit it is a bit of a gimmick, but [Adam Beedle’s] Spider-Bot did make us smile. The little robot can launch a “web” and use it to swing. It is hard to picture, but the video below will make it all clear. It can also use the cable to climb a wall, sort of.

The bot’s ability to fling a 3D printed hook on a tether is remarkable. Details are scarce, but it looks like the mechanism is spring-loaded with a servo motor to release it. Even trailing a bit of string behind it, the range of the hook is impressive and can support the weight of the robot when it winches itself up. There’s even a release mechanism that reminds us more of Batman than Spiderman.

If we were going full autonomous, we’d consider a vision system. On the other hand, you could probably tell a lot by the tension on the cable and some way to measure the angle of it coming out of the robot. If you come up with a practical use for any of this, we’d love to see it.

We’ve seen robots that fly, jump, and can climb walls before. We don’t remember one that swings like Tarzan.

Continue reading “Grappling Hook Robot Swings Like Spiderman” →