Human hands are remarkable pieces of machinery, so it’s no wonder many robots are designed after their creators. The amount of computation required to properly attenuate the grip strength and position of a hand is no joke though, so what if you took a tentacular approach to grabbing things instead?
Inspired by ocean creatures, researchers found that by using a set of pneumatically-controlled tentacles, they could grasp irregular objects reliably and gently without having to faff about with machine learning or oodles of sensors. The tentacles can wrap around the object itself or intertwine with each other to encase parts of an object in its gentle grasp.
The basic component of the device is 12 sections “slender elastomeric filament” which dangle at gauge pressure, but begin to curl as pressure is applied up to 172 kPa. All of the 300 mm long segments run on the same pressure source and are the same size, but adding multiple sized filaments or pressure sources might be useful for certain applications.
Of the body’s organs, the lungs are among the trickiest to take a biopsy and treat cancer in, both due to how important they are, as well as due to their inaccessibility. The total respiratory surface within the average human lungs is about 50 to 75 square meters. Maneuvering any kind of instrument down the endless passages to reach a suspicious area, or a cancerous region to treat is nearly impossible. This has so far left much of the lungs inaccessible.
The standard of care for lung cancer is generally surgical: remove parts of the lung tissue. However, a proposed new method using magnetic tentacles may soon provide a more gentle approach, as described in Nature Engineering Communicationsby Giovanni Pittiglio and colleagues (press release).
The tentacles are made out of a silicone substrate with embedded magnets that allow for it to be steered using external magnetic sources. With an embedded laser fiber, the head of the tentacle can be guided to the target area, and the cancerous tissue sublimated using an external laser source. In experiments on cadavers with this system, the researchers found that they could enter 37% deeper into the lungs than with standard equipment. The procedure was also completed with less tissue displacement.
Considering the high fatality rate of lung cancers, the researchers hope that this approach could soon be turned into a viable therapy, as well as for other medical conditions where a gentle tentacle slithering into the patient’s body could effect treatments previously considered to be impossible.
Heading image: Close-up of a magnetic tentacle robot next to a phantom bronchiole (Credit: University of Leeds)
The researchers at Westlake University in China found inspiration in elephant trunks. Elephant trunks are entirely devoid of bone but use a tubular muscle structure. By deforming certain muscles, complex motion is possible. After understanding how they work, it was just a matter of making a similar structure from artificial muscle fibers.
The resulting actuator uses smart materials and has eleven different morphing modes — more than other attempts to build similar structures. The fabrication sounds difficult, it involves stretching chemically reactive materials over a form with specific winding angles.
The fibers react to light. Depending on the configuration, the stalk can seek light or avoid light. We were hoping the “Materials and Methods” section would give some ideas of how to do this ourselves, but it looks like you’d need some uncommon liquid crystal materials, and you’d also have to work out some of the details.
Each player uses a pair of two-axis control sticks and a foot pedal to operate a cable-driven tentacle with a gripper on the end. These are two stage tentacles, meaning that the top and bottom halves are independently controlled. The tentacles consist of a series of laminated foam discs clued onto bicycle cable sleeves. The cables are open in the section they control, and operate in a push-pull arrangement. The spring-loaded grippers are operated by the foot pedals, with a single cable running down the center of the tentacle.
The game looks quite fun and challenging, and we can imagine it being even more entertaining with teams of two or three people operating each tentacle. Add a bit of alcohol to adult players, and it might become downright hilarious, although the mechanisms would need to be beefed up a bit to survive that level of punishment.
We all bring our own areas of expertise to our work when we build the projects that find their way in front of Hackaday writers, for instance a software developer brings clever brains to their microcontroller, or an electronic engineer might bring a well-designed piece of circuitry. [Yvo de Haas] is a mechanical engineer, and it’s pretty clear from his animatronic tentacle that he has used his expertise in that field to great effect.
If you think it looks familiar then some readers may recall that we saw a prototype model back in February at Hacker Hotel 2020. In those last weeks before the pandemic hit us with lockdowns and cancellations he’d assembled a very worthy proof of concept, and from what we can see from his write-up and the video below he’s used all the COVID time to great effect in the finished product. Back in February the control came via a pair of joysticks, we’re particularly interested to see his current use of a mini tentacle as a controller.
At its heart is a linkage of 3D-printed anti-parallelograms linked by gears, with cables holding the tension and controlling the movement of the tentacle from a set of winches. The design process is detailed from the start and makes a fascinating read, and with its gripper on the end we can’t wait for an event that goes ahead without cancellation at which we can see the tentacle for real.
The North Sea in a winter storm is a spectacular sight, one of foam-crested waves and squalls driven on the gale. It’s not a place to spend a lot of time if you are a land-lubber, so to cross it twice in a few weeks must mean there is something very much worth seeing on its other side.
More of that exotic cruise ship lifestyle.
But one of the best antidotes to February weather in the European hacker community was Hacker Hotel 2020. Around 350 people came from all the countries of the northwest of the continent to the comfort and hospitality of the Westcord Hotel de Veluwe in the eastern Netherlands, to experience a hacker camp with all the convenience and luxury of a resort hotel rather than a muddy field.
Three days in this environment results in a camp that’s just a bit special, and one that’s very much worth a visit if your range extends this far.
An Upscale Hotel Gets The Hacker Treatment
The Hacker Hotel badge 2020 has many hidden depths
Our small party of Brits arrived a day early, on a damp Thursday morning ready to lend a hand with the set-up. Slowly an upscale business conference centre was transformed into a hacker camp venue, with conference rooms turned into lecture halls, lighting and video equipment in place and 3-phase power cables snaking along the skirting boards. A large hardware hacking area was set up in one wing of the building, then the EventInfra people came in and laid out a hacker-camp-grade wireless and wired network that delivered connectivity everywhere. The contrast between the two worlds is significant, but together they make for a unique experience.
One by one, hackers arrived from all points of the compass, bearing crates of the usual cool stuff. An amateur TV satellite earth station, a brace of oversized delta 3D printers, a coin-pushing game that’s familiar from other camps. And smaller projects; little roving robots, indoor-sized multirotors, and several crates of outdated Chinese photo-frames that it’s said can be hacked to run a Linux distro.
This is the lifeblood of a hacker camp, but of course the signature piece of hardware for any hacker camp is its badge. In this Hacker Hotel 2020 didn’t disappoint, with a beautifully designed Ancient Egyptian-themed badge that concealed an array of puzzles across multiple levels. We’ll cover the badge in detail in a separate piece, but suffice to say that it is something of a tour de force. For now let’s jump into all of people and activities on offer at the con.
Welcome back to the final chapter in our journey exploring two-stage tentacle mechanisms. This is where we arm you with the tools and techniques to get one of these cretins alive-and-kicking in your livingroom. In this last installment, I’ll guide us through the steps of building our very own tentacle and controller identical to one we’ve been discussing in the last few weeks. As promised, this post comes with a few bonuses:
Depending on your situation, some design files may be more important than others. If you just want to get parts made, odds are good that you can simply cut the pre-offset DXFs from the right plate thicknesses and get rolling. Of course, if you need to tune the files for a laser with a slightly different beam diameter, I’ve included the original DXFs for good measure. For the heavy-hitters, I’ve also included the original files if there’s something about this design that just deserves a tweak or two. Have at it! (And, of course, let us know how you improve it!)
Ok, now that we’ve got the parts on-hand in a pile of pieces,let’s walk through the last-mile tweaks to making this puppet work: assembly and tuning. At this point, we’ve got a collection of parts, some laser-cut, some off the shelf. Now it’s time to string them together.
