Making A Robot To Serve Some Mean Badminton Shuttlecocks

August 30, 2026 by Maya Posch 2 Comments

Sometimes regarded as a less violent form of tennis, badminton is still a pretty challenging sport. One which suffers like so many sports from requiring at least two players since magically flying balls and shuttlecocks haven’t been invented yet. After years of tinkering on a shuttlecock serving robot, [Travis Mitchell] hit upon the idea to convert a small industrial robotic arm for the purpose.

The target of this conversion is a positively cute-sized Denso VS050 robotic arm, with Denso helpfully providing a 3D model of the arm as a solid jumping-off point in a CAD project. Here the task of the robotic arm is two-fold: one is to grab a fresh shuttlecock from a hopper with a pneumatic grabber, the other is to feed it into the spinning wheels that grip and launch it. Fortunately [Travis] has a pretty tricked-out workshop available, including the ability to 3D print metal parts, making building the prototype a snap.

After initially thinking of using a Raspberry Pi Pico, he ended up using an ATmega AVR due to the input-output requirements when communicating with the arm. Using a height-adjustable desk as the base, the whole assembly was put together for some testing on the badminton court.

With most of the testing having been done in the shop already, the remaining issue was to determine the best disc material, as the two high-speed discs that grip the shuttlecock must be well-balanced and not stretch too much. Ultimately a 3D printed plastic disc with a silicone strip as gripping surface was found to work pretty well, allowing for the robot to finally start serving its function.

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Low(er)-Cost Humanoid Robot Leverages DIY Actuators

August 30, 2026 by Donald Papp 11 Comments

Humanoid robots, even scaled-down ones, tend to be expensive. The Berkeley Humanoid Lite offers a more accessible and economical option by centering the design around 3D printed actuators that make up the bulk of the robot’s frame.

The actuators are made by combining motors with printed cycloidal gearboxes and an embedded magnetic encoder. They’re modular, so even if one has no desire to recreate the whole robot it might be worth checking out the actuator design details to see if they might be useful in some other way.

The Berkeley Humanoid Lite isn’t a finished product so much as an open-source, easily customized reference design. The GitHub repository contains everything one might need, and you can watch some basic demonstrations, including VR-driven teleoperation, in the video embedded below.

At a total hardware cost of under $5,000 USD it’s still expensive, but much more economical than other humanoid robots, open-source or not. As mentioned, even if one doesn’t plan to build one, the modular actuator design is worth keeping in mind for other purposes.
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This Library Needs To Be At Least… Three Times Bigger

August 28, 2026 by Bryan Cockfield 15 Comments

Many of us have noted a tremendous price increase in many computer components for some mysterious reason. Whatever this cause is will be debated among the various modern philosophers and Diogeneses, but regardless of cause we all still have to live in this world and make do. That turns us towards getting maximum value from the things we already have rather than trying to go out and buy more computer components right now, like [svofski] using his vast swath of existing microSD cards to build an SD card library.

The library is based around a tiny robotic arm that can physically grip the cards and move them in and out of a reader. The first iteration of the arm involved rotating the two pincers, but this turned out to be overly complicated and [svofski] eventually settled on a design resembling a rack and pinion that slides the two pincers together instead. With the gripper sorted out, it’s placed in system called T-bot arrangement, similar to coreXY kinematics, that lets it pick and place among 12 microSD card slots.

Many of the parts in this build were directly from or inspired by 3D printers, making it relatively simple with so many parts available. [svofski] didn’t build it for a specific use case, though; mostly it was constructed out of fascination for robotic tape changers which perform a similar function. But for anyone who actually needs to duplicate a large number of SD cards, or other types of removable media, this could prove to be a fairly handy robot.

3D-Printed Skin Gives Robots The Sensation Of Touch

August 24, 2026 by Maya Posch 6 Comments

Schematic diagram of the touch-sensitive skin. (Credit: Haofeng Chen et al., ArXiv, 2026)

Hypoesthesia, more commonly referred to as numbness, is one of the more distressing ailments that can affect us humans, primarily because it reminds us of just how much we rely on our sensation of touch in daily life. From experiencing the world around us, handling objects, noticing when you just bumped into that side table again and the comforting hug of a fellow human being, touch is perhaps the most important of our senses.

In that regard the recently published research by [Haofeng Chen] et al. on giving robots a skin that can experience touch seems rather important as it would give especially humanoid robots a more natural way to interact with their environment, using feedback from touch. Continue reading “3D-Printed Skin Gives Robots The Sensation Of Touch” →

Using Acoustic Resonators As Thrusters For Small Robots

August 17, 2026 by Maya Posch 1 Comment

There are quite a few rather unconventional methods of propulsion, but perhaps one of the more curious approaches involved Helmholtz resonance, as demonstrated by [Junsun Hwang] et al. with a paper in Science Advances and associated summary article by EPFL’s School of Engineering.

Although probably better known from something like musical instruments, Helmholtz resonance can be used for more than creating or deadening noise. If stimulated with an external acoustic source that matches the chamber’s resonance frequency the result is a jet of air at the neck of the chamber. This acoustic actuation can thus be used for a number of applications.

In the paper a number of such applications are demonstrated, including a boat with three of these chambers for propulsion and steering, as well as a microflier (see above image) that when placed above an ultrasonic phased area will hover due to the production of this jet of air.

This microflier concept was then adapted with angled resonator chambers so that they could drive a propeller. Naturally, the produced thrust is only a fraction of a Newton so it’s essential to make these structures as light as possible, in the order of micrograms. These microfliers were created using high-resolution 3D printing, with a few iterations attempted to determine the optimal configuration.

In the case of the boat the ultrasonic transducers were directly placed on the bottom of the resonance chamber, but in the case of the microfliers the weight limitations necessitate these transducers to be external. Even if not the most practical kind of flying robot, as a demonstrator of this application of Helmholtz resonance for acoustic propulsion it’s pretty cool.

A test setup for an actuator is shown on a benchtop. A power supply connects to a cylindrical actuator, which has an arm pressing against a load cell. The load cell's output is shown on a computer screen, which is labelled "Torque".

Building An Actuator For A Walking Robot

August 16, 2026 by Aaron Beckendorf 2 Comments

Unlike biological systems, which can use muscles, robots that try to imitate them don’t have particularly fast, powerful, compact linear actuators available. This puts walking robots at a particular disadvantage, since they can’t spread their actuators along a limb and have to place them right at the joint. [Food for Robots] took on the challenge of building such a joint-mounted actuator, and shared the results in a recent video.

[Food for Robots] is building a walking robot, so he needed a compact, lightweight, and backdrivable actuator capable of producing 20 Newton-meters of torque. He’d previously built a largely 3D-printed actuator, but when he tried to exceed 10 Nm of torque with it, various parts kept breaking. He therefore machined the second iteration out of aluminum; since it didn’t need to be 3D printed, he switched from a Capstan drive to a planetary gearbox. The gearbox sits in the center of the actuator, inside the stator, and uses several stacked layers of gears to increase strength within the limits of a small CNC.

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A guitar stands magically on it's end in the foreground of a snowy sunrise. A large 3D-printed robot is attached to the fretboard, and a smaller robot sits over the sound hole.

Twin Guitar-Playing Robots Will Work For Tab

August 14, 2026 by Kristina Panos 13 Comments

Remember Animusic? They were these incredible animated music videos with original tunes being played by computer-generated robots. Well, the MegCell Pulse might be the coolest robots-playing-music thing we’ve seen since Animusic.

Built by [Bruce] over six years’ time, this futuristic wonder features two robots working in concert to play acoustic guitar, just like a pair of human hands would. You just feed them digital tablature, and off go the fraternal twins, with one doing the fretting, and the other doing the plucking via six individual plectrum. It’s digital music producing analog sound from a physical instrument.

How does MegCell Pulse work? It’s essentially a system of gears, magnetic actuators, and arms, contained in a 3D-printed structure. The only real limitations are that it can’t traverse the entire fretboard, nor can it slide between frets. That said, you can absolutely buy one for your own guitar via [Bruce]’s modestly-goaled Kickstarter.

The kicker here is that you can’t buy an assembled MegCell Pulse; you must print and build it yourself. Back on the upside, the most expensive supporting tier is a mere $100. For that price, you get the complete digital plans. That includes 3D print files, an assembly guide, the control software, and a parts list. Be sure to check out the demo videos embedded after the break.

We have certainly seen robots playing guitars before, although admittedly, it’s been a minute.

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