Most of the robot arms we see are cool but little more than toys. Usually, they use RC servos to do motion and that’s great for making some basic motion, but if you want something more industrial and capable, check out [Pavel’s] RR1 — Real Robot One. The beefy arm has six degrees of freedom powered by stepper motors and custom planetary gearboxes. Each joint has an encoder for precise position feedback. The first prototype is already working, as you can see in the video below. Version two is forthcoming.
When you see the thing in action, you can immediately tell it isn’t a toy. There are four NEMA23 steppers and three smaller NEMA17 motors. While there are 3D printed parts, you can see a lot of metal in the build, also. You can see a video of the arm lifting up a 1 kilogram barbell and picking up a refreshing soft drink.
To some folx, puzzles are the ultimate single-player game, but to others, they are like getting a single Tootsie Roll on Halloween. [Shane] of Stuff Made Here must fall into the latter category because he spent the equivalent of 18 work-weeks to make a robot that solves them automatically. Shots have been fired in the war on puzzles.
The goal of this robot is to beat a hybrid idea of two devilish puzzles. The first is all-white which could be solved by taking a piece at random and then checking its compatibility with every unsolved piece. The second is a 5000-piece monster painted white. There is a Moby Dick theme here. Picking up pieces like a human with fingers is out of the question, but pick-and-place machines solved this long ago, and we learn a cool lesson about how shop-air can create negative pressure. Suction. We wonder if anyone ever repurposed canned air to create a vacuum cleaner.
The meat of this video is overcoming hurdles, like a rhomboidal gantry table, helping machine vision see puzzle pieces accurately, and solving a small puzzle. [Shane] explains the solutions with the ear of someone with a technical background but at a high enough level that anyone can learn something. All the moving parts are in place, but the processing power to decode the puzzle is orders of magnitude higher than consumer machines, so that will wait for part two.
It started with [CHORL] making a promise to himself regarding constructing a new combat robot: no spending of money on the new robot.
That rule was violated (but only a little) by making his robot’s wheels out of EVA kneeling pads. EVA (Ethylene-Vinyl Acetate) is a closed-cell foam that makes for durable yoga mats, kneeling pads, and products of a similar nature. [CHORL] found a way to turn them into light but serviceable wheels for his robot: the Susquehanna Boxcar.
Nested hole saws create concentric holes. Perfect for wheels.
Here’s how the wheels were made: [CHORL] began with two hole saws. Nesting a smaller hole saw into a larger one by putting both on the same arbor created a saw with two holes, both of which were centered with respect to one another. The only problem was that this hole saw was not actually deep enough to cut completely through the thick foam. Luckily, cutting roughly halfway through on one side, then flipping the sheet over and cutting through from the other side was a good workaround. That took care of turning the thick foam sheet into round wheels.
A 3D-printed part served as a wheel hub as well as gear for the drivetrain. We want to call attention to the clever method of reinforcing the connection between the parts. [CHORL] didn’t want to just glue the geared hub directly to the surface of the foam wheel, because he suspected it might separate under stress. To address this, he designed six slots into the hub, cut matching slots into the foam wheel, and inserted six spline-like reinforcements in the form of some ABS strips he had on hand. Gluing it all together with E-6000 and leaving it to cure overnight under a weight resulted in a geared wheel assembly that [CHORL] judged to be about as round and rigid as a wheel should be, so the robot had a solution for nice light wheels that were, above all, cheap!
Lots of robots need wheels, and unsurprisingly, DIY solutions are common projects. [CHORL]’s approach here looks pretty scalable, as long as one can cut some accurate holes.
Interested in knowing more about the robot these wheels are destined for? [CHORL]’s still working on the Susquehanna Boxcar, but it’s almost done, and you can read a bit more about it (and see a few more pictures) here.
To be a professional card dealer takes considerable skill, something that not everybody might even have the dexterity to acquire. Fortunately even for the most ham-fisted of dealers there’s a solution, in the form of the Dave-O-matic, [David Stern]’s automated card dealer using a Raspberry Pi 4 with a camera and pattern recognition.
It takes the form of a servo-controlled arm with a sucker on the end, which is able to pick up the cards and present them to the camera. They can then be recognized by value, and pre-determined hands can be dealt or alternatively a random hand. It seems that the predetermined hands aren’t an aid in poker cheating, but a part of the bridge player’s art. You can see it in action in the video below the break.
We like the project, but sadly at this point we must take [Dave] to task, because while tantalizing us with enough detail to get us interested he’s slammed the door in our faces by failing to show us the code. it would be nice to think that the clamor from disaffected Hackaday readers might spur him into throwing us a crumb or two.
Four DC gear-motors are fitted to a metal chassis, each one driving a mecanum wheel. These are special wheels with rollers fitted around their circumference at an angle that allows the robot to move in all directions and rotate in various ways depending on how each wheel is driven.
On top of this highly maneuverable chassis is placed a 5-degree-of-freedom robotic arm. The robot also gets a ultrasonic sensor for avoiding objects, as well as a camera for line-following duties. The camera also allows the robot to pick up blocks and identify their color, and it can then sort them into boxes. It’s all powered by a Raspberry Pi, running a bunch of Python code to make everything happen.
MIT complains that designing a robot hand is time-consuming and takes a lot of iterations. They want to improve that using a unique approach by giving a modular hand tactile sensors. They claim this can reduce the design time down to minutes for many practical applications. For example, cutting paper. You can see a video about the paper below as well as read the text itself.
Each style of manipulator has an associated graph. Predefined elements let you assemble a palm and specialized fingers. You deform the fingers to match the use of the hand. Then a sensor that looks like a mitten provides feedback fo the task.
Ball and socket joints are useful, but making a part slide over the surface of a sphere, held by magnets, requires a lot of fiddling to get right. We admire persistence and nailing all the details. [Matthew Finlay] has been doing just that with his ball and socket robot. He’s on version six, a testament to his desire to do the idea justice. Luckily for us, he’s documented each version as he went.
Version one, made from a DIY Christmas ornament ball, had no stability around the radial axis, and oscillated badly. Version two demonstrated the problem of centering the mechanism in the ball. Version 3 fixed this problem (it’s covered in the same video). Then version four fixed many of the assembly issues and replaced the servo controllers with an Arduino, but the ‘arm’ piece was too small and mechanically iffy.
Version five used a fabricated bearing. Matthew used airsoft rounds as the balls. Not a good idea. And assembly was a nightmare. So all this progress up to version six shows his improving technique. Artists say ‘work on your process, not on your pieces’. He’s become much more analytic about what’s needed. He’s started measuring the strength of the robot, and handled issues like adding limit switches so it doesn’t crash at the limits of travel.
