Sorting trash into the right categories is pretty much a daily bother. Who hasn’t stood there in front of the two, three, five or more bins (depending on your area and country), pondering which bin it should go into? [Alvaro Ferrán Cifuentes]’s SeparAItor project is a proof of concept robot that uses a robotic sorting tray and a camera setup that aims to identify and sort trash that is put into the sorting tray.
The hardware consists of a sorting tray mounted to the top of a Bluetooth-connected pan and tilt platform. The platform communicates with the rest of the system, which uses a camera and OpenCV to obtain the image data, and a Keras-based back-end which implements a deep learning neural network in Python.
Training of the system was performed by using self-made photos of the items that would need to be sorted as these would most closely match real-life conditions. After getting good enough recognition results, the system was put together, with a motion detection feature added to respond when a new item was tossed into the tray. The system will then attempt to identify the item, categorize it, and instruct the platform to rotate to the correct orientation before tilting and dropping it into the appropriate bin. See the embedded video after the break for the system in action.
Ground plastic bits go in one end, finished 3D-prints come out the other. That’s the idea behind [HomoFaciens]’ latest build: a direct-extrusion 3D-printer. And like all of his builds, it’s made from scraps and bits most of us would throw out.
Take the extrusion screw. Like the homemade rotary encoders [HomoFaciens] is known for, it appears at first glance that there’s no way it could work. An early version was just copper wire wrapped around a threaded rod inside a Teflon tube; turned by a stepper motor, the screw did a decent job of forcing finely ground PLA from a hopper into the hot end, itself just a simple aluminum block with holes drilled into it. That worked, albeit only with basically powdered PLA. Later versions of the extruder used a plain galvanized woodscrew soldered to the end of a threaded rod, which worked with chunkier plastic bits. Paddles stir up the granules in the hopper for an even flow into the extruder, and the video below shows impressive results. We also picked up a few tips, like using engine gasket paper and exhaust sealant to insulate a hot end. And the slip coupling, intended to retract the extruder screw slightly to reduce stringing, seems brilliant but needs more work to make it practical.
The Trash Printer is a print head is intended to work with shredded plastics directly, rather than by first turning them back into a filament. Thus far, [Sam] has tested the Polypropylene and HDPE, and results are promising. While the prints aren’t of the same quality as using pre-prepared filament, the parts are still viable and fit for purpose.
The print head consists of an auger, along with a cartridge heater, which work together to push plastic to the print head. The head is constructed out of laser-cut parts and a few off-the-shelf components, making it easy to replicate. [Sam] has spent significant time honing the design, and has several ideas for ways in which it could be developed further. We’re eager to see how far this technology can go, and can’t wait to see what comes next. We’ve seen other attempts to recycle plastics for 3D printing, too. Expect to see further developments in this space coming thick and fast.
Recycling beverage cartons isn’t 100% efficient. The process yields some unusable garbage as a byproduct. Why? Because containers like juice boxes are mostly paper, but also contain plastic and aluminum. The recycling process recovers the paper fibers for re-use, but what’s left after that is a mixture of plastic rejects and other bits that aren’t good for anything other than an incinerator or a landfill. Until now, anyway!
It turns out it is in fact possible to turn such reject material into a product that can be injection-molded, as shown here with [Stefan Lugtigheid]’s SAM bird feeder design. The feeder is not just made from 100% recycled materials, it’s made from the garbage of the recycling process — material that would otherwise be considered worthless. Even better, the feeder design has only the one piece. The two halves are identical, which reduces part count and simplifies assembly.
[Stefan] makes it clear that the process isn’t without its quirks. Just because it can be injection-molded doesn’t mean it works or acts the same as regular plastic. Nevertheless, the SAM birdfeeder demonstrates that it can definitely be put to practical use. We’ve seen creative reprocessing of PET bottles and sheet stock made from 3D printed trash, but recycling the garbage that comes from recycling drink cartons is some next-level stuff, for sure.
We’ve always had a love-hate relationship with 3DBenchy, the tugboat-shaped 3D printer calibration target. On one hand, it’s incredibly useful to have a common, widely used, and challenging benchmark object to evaluate printer performance and improve tuning, but we’d somehow like to get back the countless frustrated hours we’ve spent trying to get the damn thing perfect with various printers. So, it was with no little joy that we watched the video below by [Eric R Mockler], in which he uses 3DBenchy prints to benchmark his newest acquisition: a new-in-box garbage disposal he scored off Craigslist. Take that, tugboat!
[Eric] is considering using the disposal as the first step in a failed-print-recycling method to ultimately turn the waste back into filament, presumably to print more tugboats. The tiny bits produced by the disposal should provide a reasonable substitute for pelleted plastic feedstock going into a filament extruder, if the disposal is up to the task, that is. Reasoning that any device capable of grinding chicken bones should handle little plastic tugboats just as well, [Eric] gave it shot, and found that the ⅓-horsepower disposal had no problem grinding even 100%-infill PLA prints.
The video is short and to-the-point, so we’ll even excuse the portrait orientation, just this once. If you’re considering recycling your failed prints, too, you’ll also need a filament extruder, and we’ve got you covered with a low-cost version, or a high-throughput one.
Recycling is on paper at least, a wonderful thing. Taking waste and converting it into new usable material is generally more efficient than digging up more raw materials. Unfortunately though, sorting this waste material is a labor-intensive process. With China implementing bans on waste imports, suddenly the world is finding it difficult to find anywhere to accept its waste for reprocessing. In an attempt to help solve this problem, MIT’s CSAIL group have developed a recycling robot.
The robot aims to reduce the reliance on human sorters and thus improve the viability of recycling operations. This is achieved through a novel approach of using special actuators that sort by material stiffness and conductivity. The actuators are known as handed shearing auxetics – a type of actuator that expands in width when stretched. By having two of these oppose each other, they can grip a variety of objects without having to worry about orientation or grip strength like conventional rigid grippers. With pressure sensors to determine how much a material squishes, and a capacitive sensor to determine conductivity, it’s possible to sort materials into paper, plastic, and metal bins.
The research paper outlines the development of the gripper in detail. Care was taken to build something that is robust enough to deal with the recycling environment, as well as capable of handling the sorting tasks. There’s a long way to go to take this proof of concept to the commercially viable stage, but it’s a promising start to a difficult resource problem.
How large is the cache of discarded electronics in your home? They were once expensive and cherished items, but now they’re a question-mark for responsible disposal. I’m going to dig into this problem — which goes far beyond your collection of dead smartphones — as well as the issues of where this stuff ends up versus where it should end up. I’m even going to demystify the WEEE mark (that crossed out trashcan icon you’ve been noticing on your gadgets), talk about how much jumbo jets weigh, and touch on circular economies, in the pursuit of better understanding of the waste streams modern gadgets generate.
Our lives are encountering an increasing number of “how do I dispose of this [X]” moments, where X is piles of old batteries, LCDs, desktop towers, etc. This leads to relationship-testing piles of garbage potential in a garage or the bottom of a closet. Sometimes that old gear gets sold or donated. Sometimes there’s a handy e-waste campaign that swings through the neighborhood to scoop that pile up, and sometimes it eventually ends up in the trash wrapped in that dirty feeling that we did something wrong. We’ve all been there; it’s easy to discover that responsible disposal of our old electronics can be hard.
Fun fact: the average person who lives in the US generates 20 kg of e-waste annually (or about 44 freedom pounds). That’s not unique, in the UK it’s about 23 kg (that’s 23 in common kilograms), 24 kg for Denmark, and on and on. That’s quite a lot for an individual human, right? What makes up that much waste for one person? For that matter, what sorts of waste is tracked in the bogus sounding e-waste statistics you see bleated out in pleading Facebook posts? Unsurprisingly there are some common definitions. And the Very Serious People people at the World Economic Forum who bring you the definitions have some solutions to consider too.