Roboticized 3D Printer Has Been Developing Shock Absorbing Structures For Years

May 23, 2024 by 14 Comments

Imagine you want to iterate on a shock-absorbing structure design in plastic. You might design something in CAD, print it, then test it on a rig. You’ll then note down your measurements, and repeat the process again. But what if a robot could do all that instead, and do it for years on end? That’s precisely what’s been going on at Boston University.

Inside the College of Engineering, a robotic system has been working to optimize a shape to better absorb energy. The system first 3D prints a shape, and stores a record of its shape and size. The shape is then crushed with a small press while the system measures how much energy it took to compress. The crushed object is then discarded, and the robot iterates a new design and starts again.

The experiment has been going on for three years continuously at this point. The MAMA BEAR robot has tested over 25,000 3D prints, which now fill dozens of boxes. It’s not frivolous, either. According to engineer Keith Brown, the former record for a energy-absorbing structure was 71% efficiency. The robot developed a structure with 75% efficiency in January 2023, according to his research paper.

Who needs humans when the robots are doing the science on their own? Video after the break.

Continue reading “Roboticized 3D Printer Has Been Developing Shock Absorbing Structures For Years” →

Etch-A-Sketch Camera Is Open Source

May 20, 2024 by 4 Comments

The Etch-a-Sketch was a great toy if you were somehow born with the talent to use it. For the rest of us, it was a frustrating red brick filled with weird grey sand. [Every Flavor of Robot] has taken the irritating knob-encrusted oblong and turned it into something we can all enjoy, however, by building an Etch-a-Sketch camera!

The build is simple. It uses an ESP32 microcontroller to run the show, equipped with a camera. The camera is used to take a photo of the subject, and the image is then sent to a desktop computer. The desktop runs the image through an AI pipeline that generates a simplified version of the image, and the necessary G-Code to draw it on the Etch-A-Sketch. The toy’s knobs are operated by a pair of brushless motors which have been geared down to provide more torque.

It’s a neat project, and more details are available on GitHub. We’ve seen some other great mechanized Etch-a-Sketch builds before, too.

Continue reading “Etch-A-Sketch Camera Is Open Source” →

Möbius String Robot Goes Round And Round

May 19, 2024 by 9 Comments

While it doesn’t look like a traditional robot, the hydrogel robot from [Zi Liang Wu] forms a möbius strip and can be activated by light. They also experimented with shaping the hydrogels as a Seifert ribbon.

The key is that the hydrogels contain gold nanoparticles. Light heats the gold particles and this causes the hydrogels to move. The connections between the strips of hydrogels causes them to move in predictable ways. You can see a video about the experiments below.

These robots aren’t going to be for warehouse or factory work. But they can do tasks like collecting plastic beads, something difficult for conventional robots to do. They also hope to demonstrate that these soft robots could work in the body for taking samples or delivering a drug, although it isn’t apparent how light would get to them inside your body.

The dark side of the material tends to turn towards the light. The continuous loop structure means it never runs to the end of its travel. Watching it move on a string is pretty impressive.

Crawling and slithering robots may be the answer for certain specialized applications. After all, it works well in nature.

Continue reading “Möbius String Robot Goes Round And Round” →

Emulating Biology For Robots With Rolling Contact Joints

May 17, 2024 by 9 Comments

Joints are an essential part in robotics, especially those that try to emulate the motion of (human) animals. Unlike the average automaton, animals are not outfitted with bearings and similar types of joints, but rather rely sometimes on ball joints and a lot on rolling contact joints (RCJs). These RCJs have the advantage of being part of the skeletal structure, making them ideal for compact and small joints. This is the conclusion that [Breaking Taps] came to as well while designing the legs for a bird-like automaton.

These RCJs do not just have the surfaces which contact each other while rotating, but also provide the constraints for how far a particular joint is allowed to move, both in the forward and backward directions as well as sideways. In the case of the biological version these contact surfaces are also coated with a constantly renewing surface to prevent direct bone-on-bone contact. The use of RCJs is rather common in robotics, with the humanoid DRACO 3 platform as detailed in a 2023 research article by [Seung Hyeon Bang] and colleagues in Frontiers in Robotics and AI.

The other aspect of RCJs is that they have to be restrained with a compliant mechanism. In the video [Breaking Taps] uses fishing line for this, but many more options are available. The ‘best option’ also depends on the usage and forces which the specific joint will be subjected to. For further reading on the kinematics in robotics and kin, we covered the book Exact Constraint: Machine Design Using Kinematic Principles by [Douglass L. Blanding] a while ago.

Continue reading “Emulating Biology For Robots With Rolling Contact Joints” →

This Robot Picks Locks, If You’re Very Patient

May 5, 2024 by 17 Comments

We all know the Hollywood trope of picking a lock with a paperclip, and while it certainly is doable, most reputable locks require slightly more sophisticated tools to pick effectively. That’s not to say that wire is off the table for locksports, though, as this cool lock-picking robot demonstrates.

The basics behind [Sparks and Code]’s design are pretty simple. Locks are picked by pushing pins up inside the cylinder until they line up with the shear plane, allowing the cylinder to turn. Normally this is done a pin at a time with a specialized tool and with a slight bit of torque on the cylinder. Here, tough, thin, stiff wires passing through tiny holes in a blade shaped to fit the keyway are used to push all the pins up at once, eliminating the need to keep tension on the cylinder to hold pins in place.

Sounds simple, but in practice, this looks like it was a nightmare. Getting five wires to fit into the keyway and guiding them to each pin wasn’t easy, nor was powering the linear actuators that slide the wires in and out. Applying torque to the lock was a chore too; even though tension isn’t needed to retain picked pins, the cylinder still needs to rotate, which means moving the whole picking assembly. But the biggest problem by far seems to be the fragility of the blade that goes into the keyway. SLA might not be the best choice here; perhaps the blade could be made from two thin pieces of aluminum with channels milled on their faces and then assembled face-to-face.

The robot works, albeit very slowly. This isn’t [Sparks and Code]’s first foray into robot lock picking. His previous version attempted to mimic how a human would pick a lock, so this is really thinking outside the box.

Continue reading “This Robot Picks Locks, If You’re Very Patient” →

Source Code To The 1999 FPS Game Descent 3 Released

April 17, 2024 by 48 Comments

On April 16th of this year, [Kevin Bentley] released the source code to the Sci-Fi FPS game Descent 3. Originally released in 1999 for Windows, the game has you control a flying ship which you have to guide through both in- and outdoor environments, while shooting at robots that have been infected with an alien virus as you try to save the solar system. It was later also ported to Mac OS and Linux, but was considered a commercial flop due to low sales.

As one of the original developers, [Kevin] explains that one of the goals of this code release is to give the game a second life, by cleaning up the C++ code and using new APIs. Original proprietary audio and video libraries from Interplay were removed, which means that some work is required before one can build a fresh copy of the game from this code base. That said, the released code is the latest 1.5 patch level, with the Mac OS and Linux support. Even if the original Descent games weren’t your cup of tea, it’s still great to see games being preserved and updated like this.

Thanks to [Phil Ashby] for the tip.

Laser cut bug body with pincers and electronics to control the pincers

A Buggy Entry In The Useless Robot Category

April 14, 2024 by 1 Comment

No one loves a useless robot more than we do here at Hackaday. But if anyone does it might be [ARC385] with her Bug Bite Bot.

A true engineering marvel, [ARC385]’s bug bot extinguishes the candle on its own little birthday cupcake. Yup. That’s it! Even more peculiar, (and to be fair, somewhat fittingly) before her bug releases its less-than-crushing bite, it plays itself a little Happy Birthday jingle. Seems legit.

If you choose to build this little bug yourself, you’ll be happy to know that the electronics on this build are pretty straightforward. Servo motors control the pincers and a photoresistor detects the flame. [ARC385] tried using a flame sensor instead of the photoresistor, but mentioned she couldn’t get consistent performance at her required sensing distance. She also mentions that you’ll probably need to calibrate the photoresistor to ambient light if for whatever reason you choose to embark on this build yourself.

[ARC385] did a pretty good job with the laser-cut plywood to construct the bug, but using plywood adds a few more question marks to this already puzzling build. She even mentioned having to modify the pincers so they wouldn’t catch fire trying to extinguish the candle.

Would be cool if the candle could rekindle itself, but we can’t possibly support making this hack even more of a fire hazard than it already is.

Continue reading “A Buggy Entry In The Useless Robot Category” →