Putting a 3D printer on a mobile robotic platform is one thing, but two robots co-cooperatively printing a large object together is even more impressive. AMBOTS posted the video on Twitter and we’ve embedded it below.
The robots sport omnidirectional wheels and SCARA format arms, and appear to interact with some kind of active tabletop to aid positioning. The AMBOTS website suggests that the same ideas could be used for other tasks such as pick and place style assembly work, and the video below of co-operative 3D printing is certainly a neat proof of concept.
As a side note: most omni wheels we see (such as the ones on these robots) are of the Mecanum design but there are other designs out there you may not have heard of, such as the Liddiard omnidirectional wheel.
3D printing is well-suited to cranking out tank tread designs, because the numerous and identical segments required are a great fit for 3D printing’s strengths. The only hitch is the need for fasteners between each of those segments, but [AlwynxJones] has a clever solution that uses plentiful hard plastic spheres (in the form of 6 mm airsoft BBs) as both a fastener and a hinge between each of the 3D printed track segments.
Each segment has hollows made to snugly fit 6 mm BBs (shown as green in the image here) which serve both as fasteners and bearing surfaces. Assembly requires a bit of force to snap everything together, but [AlwynxJones] judges the result worth not having to bother with bolts, wires, or other makeshift fasteners.
Bolts or screws are one option for connecting segments, but those are heavy and can get expensive. Segments of printer filament have been successfully used in other tread designs, though that method requires added work in the form of either pins, or heat deforming the filament ends to form a kind of rivet. This design may be a work in progress, but it seems like a promising and clever approach.
In the era of social media, events such as the fire at Notre Dame cathedral are experienced by a global audience in real-time. From New York to Tokyo, millions of people were glued to their smartphones and computers, waiting for the latest update from media outlets and even individuals who were on the ground documenting the fearsome blaze. For twelve grueling hours, the fate of the 850 year old Parisian icon hung in the balance, and for a time it looked like the worst was inevitable.
The fires have been fully extinguished, the smoke has cleared, and in the light of day we now know that the heroic acts of the emergency response teams managed to avert complete disaster. While the damage to the cathedral is severe, the structure itself and much of the priceless art inside still remain. It’s far too early to know for sure how much the cleanup and repair of the cathedral will cost, but even the most optimistic of estimates are already in the hundreds of millions of dollars. With a structure this old, it’s likely that reconstruction will be slowed by the fact that construction techniques which have become antiquated in the intervening centuries will need to be revisited by conservators. But the people of France will not be deterred, and President Emmanuel Macron has already vowed his country will rebuild the cathedral within five years.
It’s impossible to overstate the importance of the men and women who risked their lives to save one of France’s most beloved monuments. They deserve all the praise from a grateful nation, and indeed, world. But fighting side by side with them were cutting-edge pieces of technology, some of which were pushed into service at a moments notice. These machines helped guide the firefighters in their battle with the inferno, and stood in when the risk to human life was too great. At the end of the day, it was man and not machine that triumphed over nature’s fury; but without the help of modern technology the toll could have been far higher.
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.
When I read old books, I like to look for predictions of the future. Since we are living in that future, it is fun to see how they did. Case in point: I have a copy of “The New Wonder Book of Knowledge”, an anthology from 1941. This was the kind of book you wanted before there was a Wikipedia to read in your spare time. There are articles about how coal is mined, how phonographs work, and the inner workings of a beehive. Not the kind of book you’d grab to look up something specific, but a great book to read if you just want to learn something interesting. In it there are a few articles about technology that seemed ready to take us to the future. One of those is the Televox — a robot from Westinghouse poised to usher in an age of home and industrial mechanical servants. Robots in 1941? Actually, Televox came into being in 1927.
If you were writing about the future in 2001, you might have pictured city sidewalks congested with commuters riding Segways. After all, in 2001, we were told that something was about to hit the market that would “change everything.” It had a known inventor, Dean Kamen, and a significant venture capitalist behind it. While it has found a few niche markets, it isn’t the billion dollar personal transportation juggernaut that was predicted.
But technology is like that. Sometimes things seem poised for greatness and disappear — bubble memory comes to mind. Sometimes things have a few years of success and get replaced by something better. Fax machines or floppy drives, for example. The Televox was a glimpse of what was to come, but not in any way that people imagined in 1941. Continue reading “Televox: The Past’s Robot of the Future”→
It’s fair to say that building electronic gadgets is easier now than it ever has been in the past. With low-cost modular components, there’s often just a couple dozen lines of code and a few jumper wires standing between your idea and a functioning prototype. Driving stepper motors is a perfect example: you can grab a cheap controller board, hook it up to a microcontroller, and the rest is essentially just software. But recently [mechatronicsguy] wondered if even that was more hardware than was technically necessary to get the job done.
It’s not that he was intentionally looking to make things more complicated for himself, of course. His rationale was entirely economic; if you’re looking to drive a dozen or more stepper motors, even the “cheap” controllers can add up. So he started to wonder if he could skip the controller entirely and connect the stepper motor directly to the digital pins of an Arduino. Generally speaking this is a bad idea, but if you’re careful and are willing to take the risk, [mechatronicsguy] is living proof it’s possible
So what’s the trick to running a whopping seventeen individual stepper motors directly from the digital pins of an Arduino Mega? Well, to start with you’re not going to be running the beefy NEMA 17 motors like you might find in a 3D printer. [mechatronicsguy] is using the diminutive (and dirt cheap) 28BYJ-48, a light duty stepper used in many consumer products. Even with this relatively tiny motor, you need to crack open the case and cut a trace on the PCB to switch it from unipolar to bipolar.
Beyond that, you need to be careful. [mechatronicsguy] reports he’s had success running as many as ten of them at once, but realistically the fewer operating simultaneously the better. This is actually made easier due to the relatively poor specs of the 28BYJ-48 motor; its huge eleven degree step size means its not really susceptible to the same kind of slippage you’d get on a NEMA 17 when powered down. This means you can cut power to all but the actively moving motor and be fairly sure they’ll all stay where you left them.
While we’ve come a long way in terms of opening up the world of radio control to open source software, a good deal of the hardware itself is still closed up. You can flash a cheap RC transmitter with a community developed firmware, in fact there’s a decent chance that’s what it ships with, but the hardware itself is still an immutable black box. That might be fine if you’re just flying an RC plane or quadcopter, but what if you’ve got something a bit more advanced in mind?
From his personal experience, [Alireza] found that traditional RC transmitters have their limits when you start using them for robotics. You’ll often want input schemes or devices which would never occur to the remote’s designers, and you’ll almost certainly want to have more channels and functions than the original hardware will allow. One of the big advantages with the Alpha V1 is that the front and back of the controller are simple acrylic panels, meaning you can easily cut openings or drill holes in them to add more hardware without having to deal with the (relatively) ergonomic shapes of a traditional transmitter.
Of course, that’s only one half of the equation. When you add new hardware, you’ll need to make the software aware of it. To that end, [Alireza] says he and his team have developed a library of adaptable firmware modules which should make it very easy to add in new components without having to get bogged down with software configuration. In fact, he says the goal is to allow the user to add new hardware to the Alpha V1 without requiring them to write a single line of code.
The Alpha V1 communicates at 2.4 GHz using either XBee or Murata DNT24 radios, and supports as many as 72 individual channels as well as two-way telemetry. If your requirements aren’t quite so high, we recently covered a significantly less intimidating attempt at building an open source RC transmitter that might suit your needs.
Each segment has hollows made to snugly fit 6 mm BBs (shown as green in the image here) which serve both as fasteners and bearing surfaces. Assembly requires a bit of force to snap everything together, but [AlwynxJones] judges the result worth not having to bother with bolts, wires, or other makeshift fasteners.
