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Robot Repeatedly Rearranges Remnants In The Round

Sisyphus is an art installation by [Kachi Chan] featuring two scales of robots engaged in endless cyclic interaction. Smaller robots build brick arches while a giant robot pushes them down. As [Kachi Chan] says “this robotic system propels a narrative of construction and deconstruction.” The project was awarded honorary mention at the Ars Electronica’s Prix Ars 2022 in the Digital Communities category. Watch the video after the break to see the final concept.

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[Kachi Chan] developed the installation in pre-visualizations and through a series of prototypes shown in a moody process film, the second video after the break. While the film is quite short on details, you’ll see iterations of the robot arm and computer vision system. According to this article on the project [Kachi Chan] used Cinema 4D to simulate the motion, ROS for control, PincherX150 robotic arms modified with Dynamixel XM 430 & XL430 servo motors, and custom 3D prints.

We’ve covered another type of Sisyphus project, sand tables like this and the Sisyphish. Continue reading “Robot Repeatedly Rearranges Remnants In The Round”

Sisyphean Ball Race Robot Toils Gracefully, Magnetically

Aren’t ball races and marble runs fun? Wouldn’t they be so much more enjoyable if you didn’t have to climb back up the ladder each time, as it were, and reset the thing? [Johannes] wrote in to tell us about a wee robot with the Sisyphean task of setting a ball bearing on a simple but fun course, collecting it from the end, and airlifting it back to the start of the track.

[Johannes] built this ‘bot to test small-scale resin printing strength as well as the longevity of some tiny linear actuators from Ali that may or may not be available at a moment’s notice. The point was to see how these little guys fared when connected directly to an Arduino or other microcontroller, rather than going the safer route with a motor driver of some kind.

Some things worked well, like the c-clips that keep the axles together, and using quick pulses to release the magnetically-linked ball from the gripper. Other aspects didn’t work out so well. Tiny resin parts do not respond well to force, for starters. And then there’s the actuators themselves. The connections are fragile and the motors are weak, but they vary wildly in quality from piece to piece, so YMMV. Some lose steps, and others occasionally seize. But you wouldn’t know any of that from the graceful movement capture in the video below. Although it appears to be automated, the bot is under remote control because of the motor issues.

Not into ball runs? There are other Sisyphean tasks available, such as moving sand around in the name of meditation.

Continue reading “Sisyphean Ball Race Robot Toils Gracefully, Magnetically”

Aquarium Plotter Shows Sisyphish’s Submerged Sand Stripes

Sisyphus is cursed to roll a boulder up a hill for eternity. Pet fish generally content themselves to swimming the same lap over and over in a glass tank. Perpetuity can be soothing, so long as you’re not shouldering a boulder.

[Zach Frew] wants to integrate and automate the boulder on a smaller scale and one that can benefit his aquarium full of colorful Taiwanese bee shrimp. Instead of an inert rock and a Greek, Sisyphish uses a magnet and servo motors connected to a microcontroller to draw Spirograph-style shapes in the tank’s sand.

There are a couple of gears beneath the tank to trace the geometric patterns but they’re clear of any water. One gear rotates about the center of the cylindrical tank while the other holds a magnet and adjusts the distance from the center. Pilots, and select nerds, will recognize this as rho-theta positioning. Despite the uncommon coordinate system, the circular plotter accepts G-code. We love when math gets turned into gorgeous designs, and shrimp love when those tasty microbes get shaken from their gravelly hiding places.

We adore the dry sand plotters that came before, and Sisyphus himself appeared in a LEGO format that made us question our proficiency with the blocks.

Continue reading “Aquarium Plotter Shows Sisyphish’s Submerged Sand Stripes”