The Hexa-Bouncer May Be The Most Overengineered Thing You See This Week

October 12, 2026 by Tyler August 6 Comments

Sometimes, you want to build a simple project– the minimum viable product that solves your problem and nothing else. Other times you might be feeling a little extra, and want to use oodles of machined aluminum, six steppers, two cameras, a Teensy and a PC with a GPU just to bounce a ball. That’s the mood behind [T-Kuhn]’s hexa-bouncer, a Stewart Platform on steroids. You can read all about it on his blog or witness it in action in the video below. Trust us, really have to see it in action.

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A pair of red, articulated, 3D printed hands are being used to pour water from a plastic bottle into a glass. One hand holds the bottle, and one holds the glass.

Building A Cheap, Dexterous Robot Hand

October 5, 2026 by Aaron Beckendorf 10 Comments

Most of the time, assuming nothing’s gone wrong with them, we take our hands so much for granted that it’s easy to forget what remarkable pieces of engineering they are: not only are they precise and sensitive enough to crack an egg or write a signature, but also strong enough to lift a weight or swing a hammer. Such performance has thus far eluded robot hands, but fortunately few tasks require it; the main challenge is dexterity, which is where [Vittorio Lumare]’s low-cost Yeah Hand could help.

The Yeah Hand is mostly 3D-printed and uses five servo motors per hand; like a human hand, it has no actuators within the fingers themselves, instead using fishing-line tendons to transfer motion from the motors. To reduce friction and keep the motors from overheating, each tendon runs through guides made from PTFE Bowden tubes; in tests, the hand ran 800 cycles of opening and closing without even getting close to overheating. The hand can lift up to eight kilograms and apply a maximum grasping force of five kg. For better grip, each finger has silicone grips along the inner surface, which let it hold smooth objects quite steady; to pick up fine objects, the thumbs have thumbnails.

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Pogo-Bot Goes All Terrain With Compliant Foot

September 30, 2026 by Tyler August 19 Comments

What do you get when you combine a pogo stick, a quadcopter, and engineering students from the University of Toronto? This thing, apparently– a “monopedal hopping robot” that uses a spikey, pivoting foot pad tensioned by what look like elastic bands to keep it upright on all terrain from soft sand to hard ice.

It’s an interesting concept. The thrust from the four propellers is what gives the energy to get the robot moving, but its pogo-like hopping is entirely down to the spring-loaded single legged “landing gear”. Early iterations just used a spike on the end of that leg, but that failed in ways that some might find humorous, which you will see if you watch the video embedded below. Giving the monopod an actual foot with some traction and the ability to pivot and match the terrain works much better– now not only can this robot leap tall fences in a single bound, an errant ice patch won’t send it skittering away.

This isn’t the first one-legged robot we’ve seen; some only use their leg while others have wings, but this odd quadcopter is the first we’ve seen to brave Canadian winter. Continue reading “Pogo-Bot Goes All Terrain With Compliant Foot” →

Center-Pivot System Modified To Mow Lawn

September 27, 2026 by Bryan Cockfield 16 Comments

When flying over the United States, Australia, and a few other vast and relatively empty parts of the world, strange circular formations can be spotted. These are typically center-pivot irrigation systems, an effective way to irrigate crops if efficient use of space is not too big of a priority. Keeping these massive machines in a straight line is an interesting engineering problem, though, and [rctestflight] built a miniature version of his that works on the same principle but mows his lawn instead.

These systems work as semi-independent sections that are flexibly coupled at either end. The control scheme initially used here was to drive the outermost set of wheels at a constant speed, and then use limit switches at each coupling inside of that to drive inner sets of wheels once the outer set passes a setpoint. Eventually a potentiometer-based proportional controller was installed in place of the limit switches. With some other drivetrain issues sorted out it was on to building the mower attachment. This uses a pair of pivoting precision knives mounted to motors that ride along a carriage attached to any one of the linkages of the center-pivot system. Limit switches keep the carriage riding back and forth cutting the lawn as it traverses the grass.

With the system in place, [rctestflight] set out to optimize it mostly out of a desire to tinker with a thing that he had built. The challenge for him is that his location in the Pacific Northwest is generally very damp, so in addition to corrosion and other water damage on various parts, there were also issues of mud complicating the way the wheels navigated the terrain, as well as the plant growth being fairly rapid and often impeding the process of the robot as well. One of the perks, though, was that the circular area was already largely carved out thanks to some of his earlier projects testing the durability of RC cars.

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Robot Makes Literal Daisy Chains

September 24, 2026 by Donald Papp 3 Comments

[Jude Robinson]’s robot Daisy has an unusual function: making a literal chain of daisies. The device is his student final project and demonstrates how a system can replace sensing with clever mechanical constraints. Instead of bringing tools to bear on each daisy, the daisies are brought to the tools in a repeatable, deterministic way.

Daisy is essentially two X-Y gantries with grippers facing one another. Between them is a conveyor upon which daisies are fed, plus a blade at the top with a threading post nearby. A gripper takes a daisy, feeds the stem through the hole in the previous one, then lifts the new addition up to a scalpel blade which cuts a short incision. The thin threading post goes through the new hole in the new stem, ready for the next daisy to be inserted. The two gantries alternate roles, building the chain one daisy link at a time.

[Jude] says that daisy stem shape and diameter have the most impact on reliability, so it’s very important to constrain the daisies such that the scalpel and threading operations work reliably. This is primarily done with v-shaped profiles in the grippers which automatically center stems of different sizes. The sheath around the scalpel blade also plays a role in constraining and supporting the stems as they are gently pierced and sliced. Tuning these elements was a big part of making the system work.

Watch it in action in the video (embedded below) which shows how clever mechanical design can turn an uncertain problem — like how to handle daisies of different sizes — into a deterministic one with the help of clever mechanical design. That same concept is at work in everything from simple nut sorters to highly complex paper airplane machines.

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A black robotic hand is shown walking across a granite floor, using its fingers as legs.

Teaching A Robot Hand To Walk

September 19, 2026 by Aaron Beckendorf 25 Comments

Although it wasn’t apparently designed with this in mind, it seems particularly fortuitous that this walking robotic hand was released in time for Halloween. Designed by researchers from ETH Zurich, the slightly unsettling disembodied hand can use its fingers as legs to traverse terrain, push small objects around, and operate a keyboard.

The researchers started from commercially-available robot hand, equipped it with a battery and Raspberry Pi Zero 2 W, and developed neural net-based software to control it. The hand has twenty joints, four per finger, and the neural net iteratively outputs the next joint state, based on previous movements, the state of the hand, and the hand’s current goal. To train the net, the researchers built a simulated model, then used this for reinforcement learning; this yielded a faster walking speed than an adapted quadrupedal motion model did.

The hand was trained to move in a straight line, turn, recover from a fall, and press the keys of a keyboard (since it doesn’t have a camera, though, it can’t operate a keyboard by itself). The fall recovery is impressive to watch: in 21 out of 25 tests, it was able to right itself within twenty seconds. Due to the hand’s geometry, it drifts to the right while walking, so a constant correction needed to be applied. It did, however, manage to successfully cross fourteen varying surfaces, ranging in roughness from a rubber mat to gravel and grass. It even managed to push light objects toward goals.

The authors envision this kind of autonomous hand enabling greater freedom for a larger robot, such as a robot arm: if it needs to reach something farther away, the hand simply detaches and walks over. Regardless of the use to which they put in, such a project is already within reach of hackers; we’ve seen a few robotic hand projects here over the years.

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Little Droid Has Party Mode

September 10, 2026 by Zoe Skyforest 7 Comments

Remember those tiny little droids skittering around the pristine corridors of the Death Star in Star Wars? [heychaostheory] has put together something vaguely along the lines of those charming little mobile toasters. It’s an autonomous mouse droid with party mode!

The build is interesting in that it’s based on an off-the-shelf metal robot chassis—which provides mounting points for the gearmotors and wheels that make up the drivetrain. The mouse droid body sits atop this, being a 3D printed part that is afixed with heat set inserts and nylon standoffs. It’s 3D printed and expertly decorated with a fun vibe. Inside the body lives an Arduino Uno, hooked up to an L298 motor driver board and ultrasound sensors used for obstacle avoidance. It’s also got a smattering of LEDs to flash, because blinkenlights matter. The best bit, though, is the party mode button, which fires off music via a DFPlayer Mini module.

The mouse droid may not be as flashy and imposing as the Droideka or as mechanically impressive as BB-8, but that just makes it more accessible and fun to build. You can easily create one at full scale without breaking the bank. If you’re cooking up your own fun droids in the workshop, don’t hesitate to let us know. Video after the break.

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