breakpointalpha 6 hours ago

What jumps out at me is the $135 bill of materials.

What a time to be alive!

  • Animats 3 hours ago

    Feetech is selling actuators which are mechanically R/C type servos, but have a bidirectional computer interface allowing the control computer to find out what's happening at the servo.[1] This isn't new; Dynamixel has been doing it for over a decade. But not at this price point. This Feetech servo is $17, while Dynamixel units start around $70 and go much higher.[2]

    The parts list has "need to be strong" for many of the small parts, but they are 3D printed PLA plastic. That's the low end of 3D printing. None of the videos show the hand handling anything.

    So this is really the proof of concept model. If there's enough interest, someone could make the parts by injection-molding of something better, such as polycarbonate or glass-filled nylon. The total plastic volume here is so tiny that the plastic cost is negligible, and there's no reason not to use a high-quality engineering plastic.

    Nobody seems to do hobbyist injection molding much. TechShop had a desktop injection molding machine, the CNC milling machines to make molds, and even Autodesk Moldflow to design them. But nobody used those tools. A few university maker spaces have similar machines. Because most of the world's plastic stuff is made by injection molding.

    [1] https://www.feetechrc.com/

    [2] https://www.robotis.us/dynamixel/

    [3] https://makerspace.engineering.nyu.edu/machines/pim/

    • mionhe 3 hours ago

      Mold design is still difficult when the parts aren't dead simple. The software I've seen is okay with the simple stuff, but once you get even a little more complex you have to understand simultaneously how to design good parts for molding and how to design good molds, both of which are heavily dependent on the type of plastic you're using and the size of the press you have access to. Not to mention how to machine good molds from metal, which is a challenge all on its own due to surface finish and tolerance requirements (and weird geometry that makes the CAM choke...)

      In other words, we're not really there yet to bring that activity into the hobby realm. But I hope that we're not too far away.

      • Animats 2 hours ago

        They're little linkage parts, mostly flat.[1] Some of those holes are bearings. None of those parts are hard to make, but they need to be strong. They could be made by CNC machining, or in quantity by injection molding, or stamping. But tiny working parts in 3D printed PLA will be too flimsy for that hand to do much work.

        Totally fixable problem. Then this hand can go to work.

        If this thing catches on, someone might sell an upgrade kit with stronger parts. The designer is already considering a servo upgrade.

        [1] https://github.com/pollen-robotics/AmazingHand/blob/main/ass...

  • stefanka 2 hours ago

    It’s one of best designs I have seen, I admit. But for that price you cannot get absolute encoders outside the motor, reliable force/torque sensors (think picking up a strawberry), tendons (thread below). It might be too limited for research and real-world projects unfortunately.

  • jjangkke 5 hours ago

    Most hand related jobs upwards of $100 per 30 min

    If this Robot hand can do those jobs we could see some industries take a hit

    • 0_____0 5 hours ago

      People have been making end effectors using hobby servos for ages. These servomotors are designed for use in an RC aircraft, they're light, cheap, and expendable.

      Industrial needs care not about weight, care less about cost, and care a great deal about capability, repeatability, and reliability.

      This is a cool project for a hobbyist but it's not meant to be a serious industrial machine.

      Edit: what is with this thread? Lots of very generic positive comments here but not much thinking about what this is actually useful for.

      • johnmaguire 4 hours ago

        I think the confusion stems from the fact that you're responding to a joke innuendo thread.

        • stefanka 2 hours ago

          Ooooh. For _that_ application you better have either enough elasticity or reliable force/torque sensors and a good control in place.

        • trhway 2 hours ago

          They haven’t watched Big Bang Theory.

      • stronglikedan 3 hours ago

        > Lots of very generic positive comments here but not much thinking about what this is actually useful for.

        How can you say that when the person you are responding to is talking about what this is actually useful for?

      • ACCount36 4 hours ago

        ...that's how it was in year 2020.

        What you're missing is: today, we're nearing the point where actual general purpose robots become viable.

        Which means: the purpose of a robot is no longer to sit at a factory line and precisely execute the same exact motions on repeat 24/7. The purpose of the next generation of robots is to learn generalized behaviors, adapt to circumstances, and carry out circumstance-specific actions with active sensor feedback. Which means completely different requirements for effectors.

        Which means: repeatability can go get fucked, for one.

        • stefanka an hour ago

          > ...that's how it was in year 2020

          Humanoid robotics research was pretty popular in the early 2000s already, with remarkable, reproducible results not only in videos. It’s definitively more present in the media now.

        • lukan 4 hours ago

          Without repeatability, good luck tuning your robot to do anything reliable.

          • ACCount36 3 hours ago

            Real world isn't "reliable". If a robot can't correct for errors, it's not going to survive out there.

    • MisterTea an hour ago

      > upwards of $100 per 30 min

      That is why I'm self employed.

    • kakapo5672 2 hours ago

      It took me a a distressingly long time to understand this comment. I'm kind of concerned, and have vowed to get out more.

  • mrbonner 3 hours ago

    You haven’t accounted for the 3D printer yet.

  • echelon 5 hours ago

    I can't wait for this to be put on a tall roomba base so it can clean my kitchen.

Brajeshwar 6 hours ago

Here is what I’m more keen on, rather than the human-like robots that we are all expecting. For instance, I would like a wall-mounted or floor-standing multi-arm robot that serves as a kitchen assistant. One can add or reduce arms as needed/desired. It is custom-equipped with a fire extinguisher, thermometer, and the usual must-haves for a kitchen. It will hold the cutlery, plates, and other items as needed. It will also advise on the likes of, “No, salts usually go in a pinch, would you like me to add in just about 5 grams?”

Thus, similarly for the garage, the DIY table, etc. Just Arms would be good.

  • bredren an hour ago

    It slices, it dices...

    Seriously, though. Vassar Robotics (YC company) has an arm kit available for order now. The original ship date for my order just got pushed back due to an upgrade in the camera spec.

    It won't be able to hold knives (I don't think) but there are companies working to bring about your hoped-for wall arm right now.

  • thrance 6 hours ago

    Tbh I would rather not have computer-guided knife-flinging arms in my home, be them on wheels or fixed to the wall.

    • sroussey 6 hours ago

      I have a parrot (whose beak is sharp enough, thank you very much) that loves to grab a knife out of the knife block and spin around with it.

      I have to put a towel over it though today he pulled the towel off and still grabbed the knife and was holding it up when I turned around.

      • 0_____0 5 hours ago

        Like a mischievous toddler with wings...

      • seanthemon 5 hours ago

        It's a well known fact that birds aren't real and you must be a target now.

  • scotty79 5 hours ago

    I always imagined robot hands hanging and sliding on rails under top kitchen cabinets.

  • goopypoop 3 hours ago

    perhaps sir would prefer… tentacles?

mclau157 8 hours ago

Pollen Robotics and HuggingFace are doing a lot for robotics right now!

  • ge96 6 hours ago

    Wonder if it will get adopted (huggingface robot) I noticed the eyes/cameras go behind the neck thing for sleep mode

agumonkey 5 hours ago

Anybody knows of similar projects for exoskeleton or support devices?

  • Joel_Mckay an hour ago

    Yes, it is a technology originally intended to make spacesuits less brutal on astronauts hand/wrist/forearm fatigue.

    Last I checked, project was shelved in 2020 for various reasons. =3

TheAceOfHearts 3 hours ago

Does anyone know what design considerations, if any, might've gone into deciding to have 4 fingers instead of 5? And what tradeoffs that entails?

I actually saw this posted a few days back on Twitter and had been wondering if there was any deeper consideration for the number of fingers. It seems like you save around $10 in parts by getting rid of a finger, based on the information in the BOM.

  • p_d_r an hour ago

    It looks like the width of the servos driving each finger makes a certain finger spacing necessary, and I bet five made for an awkwardly wide hand.

binsquare 6 hours ago

The world is designed with humans in mind, it's great to see robotics evolve in this direction to take advantage of that!

  • baq 5 hours ago

    Literally the reason for all publicly traded robotics companies going up recently.

  • poly2it 5 hours ago

    Why was this downvoted?

FBISurveillance 3 hours ago

Great stuff. So 2x$135 and I'll finally get my t-shirts folded for me in the laundry room.

ortusdux 6 hours ago

I wonder if I have time to make one of these and then decorate it to look like Thing for Halloween!

SequoiaHope 4 hours ago

Beautiful design and I love that it’s in onshape with an aliexpress BOM. I might build this!

fitsumbelay 3 hours ago

I love that it's cartoon style -- 3 fingers and a thumb instead of four

amelius 9 hours ago

Would it be possible to have tendons running through the arms, so the weight of the hand is reduced?

  • stefanka 8 hours ago

    Most tendons materials are elastic. That lead to create calibration problems and require proprioceptive sensors in the hand

    • Symmetry 4 hours ago

      In practice force sensing is more useful than proprioception in most cases, at least for grasping. Generally you won't the dimensions of an object you're attempting to grasp anywhere near as well as you would know the shape of the hand you're using so a certain amount of underactuated compliance makes the job a lot easier.

      • stefanka an hour ago

        I agree. But even then elasticity had to be taken into account (and maybe even gravity), if the object is very delicate.

    • fusslo 8 hours ago

      Huh, never thought of that

      I wonder if companies are experimenting with materials like UHMWPE for non-elastic, high strength-to-diameter tendons.

      I dont know if you'd have to weld the dyneema to the anchor points, though

      • stefanka 7 hours ago

        Roboy used dyneema tendons if I recall correctly. Fluidic actuators is another option. IMO, additional sensors and sensor fusion are necessary but this will raise the costs and demand to control software significantly. We are researching humanoid robots for quite some decades now and these problems are easily underestimated (similarly to autonomous driving). I doubt we'll see them in our houses very soon.

        • fusionadvocate 5 hours ago

          The issue is not that these problems are easily underestimated, but that the researchers are very proficient at repeating the same mistakes over and over again.

      • imtringued 7 hours ago

        I think you're misunderstanding the essence of the problem. If you use tendons, you'll need a neural network in your control loop that can learn continuously so that it compensates rope stretch and changes in friction through wear and tear.

        A lot of problems in robotics reduce down to continual learning. Essentially all system identification tasks become obsolete the moment you have a self learning system and yet we have an AI industry preaching that AGI is around the corner without this "crutch".

        • stefanka 7 hours ago

          Not to mention that they easily break and are annoyingly tedious to be replaced (I had to assist often enough on such "surgeries" in our lab)

        • stefanka 7 hours ago

          You don't necessarily need neural networks for that, there are more specialized function approximations that learn faster and enable life-long learning for kinematics/dynamics and extrapolate better than NN which are more general purpose.

        • amelius 7 hours ago

          You could add encoder patterns to the tendons, like stripes. And then use something like a mouse-sensor to track them. This is still much lighter than servos.

          Another idea is to use an external camera or two and to track the fingers with a deep learning model. But this can become messy if other objects are in view. And it might also introduce more control delay in the feedback loop than a simple sensor.

          • stefanka 2 hours ago

            If space permits you should add absolute encoders in the joints. In a finger that’s likely a challenge. In an arm, that’s easy

        • spauldo 4 hours ago

          I would think pressure and angle sensors tied to a PID loop would suffice, but I'm not a roboticist.

          • stefanka 2 hours ago

            If you can get a feedback loop at the respective joint, then yes, this might be enough. In case of an arm (not this hand), you can often only observe the end of a chain, and then, that’s more complex

glitchc 6 hours ago

This is great, but to make a comparable hand, we also need very sensitive sensors, at minimum pressure and temperature, across the entire surface area.

  • falcor84 6 hours ago

    Absolutely, though I'd be ok with just pressure as a starter.

mandeepj 7 hours ago

The bigger or biggest question is - how much weight it can lift? If we assume it can lift half a pound, then what changes it’d require to make it lift 10/20/30 pounds and so on?

  • micromacrofoot 7 hours ago

    hands hold, arms lift — a hand without an arm isn't going to have much strength

    • horsawlarway 5 hours ago

      Yes, but this is "bring your own arm" so the person above you can easily build the arm out to whatever specs they'd like.

      They probably want to know relatively important information like

      - Breaking force (how much force will break a finger)

      - grip force (How much force can the fingers exert to hold an object once closed)

      - holding force (combination of grip force and material properties [ex - friction] that gives you an idea how much force can be applied to prevent slipping)

      - closing force (How much force is exerted during closing [similar but distinct from grip/holding])

      Or, with a lot less specific detail but still generally useful as a starting point...

      - payload capacity (approximately how much can this safely manipulate)

mft_ 8 hours ago

This looks like a nice, approachable robotic model of a human hand that can be printed and experimented with.

But... is a human hand the best design for a robot to grip things with? Or could we surmise that the human hand evolved as a pretty good hand given the materials and senses that were available to evolve humans from, while in theory a totally different design might be optimal for gripping when constructed from metal, plastic, motors, etc.?

  • LeifCarrotson 7 hours ago

    A human hand is probably the most appropriate design for a robot to grip a variety of things that were designed to be gripped by human hands.

    For any one specific thing, be it a doorknob, a rope, a sheet of paper or fabric, or a pair of scissors, there's probably a different design that's several orders of magnitude simpler and cheaper, and also much stronger and more reliable. Single-axis parallel grippers, circumferential chucks, vacuum cups/vacuum pads, electromagnets, cam lock and release mechanisms, and so on are common in industrial robotics.

    Assume your robot's only task is to grab a spool with a 35 +/-0.5 mm ID core from from an infeed rack and place it on a spindle, you're not going to try to build a five-finger human sized servo-operated hand and tuck two of those fingers away to awkwardly pinch outwards from the inside, you're going to grab a Schunk JGZ concentric gripper off the shelf and plumb a pair of air lines to it. If it also needs to grab a tab from some tape on the spool and pull it into the machine, you're just going to add an asymmetric pincer like an angular tumor on two of the jaws - or graft on an entire separate parallel gripper like some polydactyl appendage, or tool-change, amputating and reattaching hands at will.

    I have also observed that humans are quite good at anthropomorphizing robot arms: a small, well-tuned motion can be universally recognized as a nod of agreement, shrug of confusion, wave of acknowledgement, or sigh of disappointment, even if the equipment is a bright yellow 6-axis piece of cast iron with menacing claws where the hand (or face? they're often the same) should be. Googley eyes and a "Hi my name is" sticker make this even more convincing.

    But if you need a single tool to grip a doorknob, a rope, a sheet of paper, a pair of scissors, AND an unknown variety of other arbitrary household objects... it's probably best to start with an approximation of the human hand. Also, while claws may be appropriate for a work environment with the robot inside a fence, in collaborative situations hands are just less intimidating.

    • Someone 6 hours ago

      > For any one specific thing, be it a doorknob, a rope, a sheet of paper or fabric, or a pair of scissors, there's probably a different design that's several orders of magnitude simpler and cheaper, and also much stronger and more reliable.

      Also, if you’re designing a robot gripper for any one specific thing, it’s quite possible that you can tweak the design of that specific thing to make the task easier. As an extreme example, screws and screw drivers evolve in parallel.

    • turtledragonfly 6 hours ago

      As an aside, this "robot tentacle" paper was referenced in a recent HN story: "SpiRobs: Logarithmic Spiral-shaped Robots for Versatile Grasping Across Scales"[1]

      Seems like a pretty high bang-for-the-buck for versatility and capability with only a few cables controlling it.

      [1] https://arxiv.org/pdf/2303.09861

    • ctxc 6 hours ago

      Good point, well put.

  • ygjb 5 hours ago

    The question you are asking opens up a whole other field of questions. The amount of AI and robotics "in the field" is only going to increase. As that increase comes do we want to continue to build for a human capabilities and limitations, or do we want to build for machine capabilities and limitations.

    I think the ethical approach is to build for human capabilities and limitations. We have already seen what happens when we allow business to optimize for the lowest common denominator, and that is why we have regulations that emphasize accessibility. If we allow or encourage businesses to build robots that lack human capabilities and limitations that operate in the real world alongside humans, then even if those robots are assistive in nature (either a prosthetic robot hand, or a full blown humanoid robotic assistant), we will displace or redefine what humans are capable of, and diminish the role of and respect for human beings in our society.

  • hansvm 7 hours ago

    Among other things, the ability to pretrain for a task by just copying human motion is pretty powerful.

  • atrus 7 hours ago

    Depends on what you mean by best ofc :P

    If anything, the human world is built for humans, so a lot of existing things are naturally compatible with human hands. Also, take into account flexibility. It might not be the best for one job, but it's really okay at a lot of jobs.

  • beAbU 5 hours ago

    The human hand is arguably the best general purpose gripper of human-scale objects. Only took evolution a couple of hundred million years to figure it out.

    If you can limit the scope of things to be gripped, e.g. a sheet of paper, a baby chicken or a 100x100mm square steel girder then no doubt there is a better design out there.

    • eichin 2 hours ago

      Not exactly. The human hand is really advanced within the constraint of "you can't just arbitrarily replace damaged parts". If you can swap in replacement fingers, 3 of them is fine (and much easier to model and perform grasping calculations.)

  • magicmicah85 7 hours ago

    Is there a better design? I ask this genuinely, I really don't know but I suspect that the human hand is versatile enough to allow it to be programmable for a variety of tasks.

  • a_wild_dandan 7 hours ago

    Our modern world was built for hand-havers, so we build hand-havers for general interaction with the modern world. This vicious cycle will end, but a certain amount of inertial clunkiness is inevitable in nascent technological disruptions. Especially in moments as grand as the second industrial revolution.

  • bigmadshoe 8 hours ago

    It’s easier for humans to train a human hand

  • espadrine 6 hours ago

    I agree that there are some robotic designs that unnecessarily mimic human limbs. I have in mind heads, and feet (instead of wheels).

    A hand however, is useful because so many manufactured objects have been constructed for their purpose.

    • swiftcoder 6 hours ago

      Feet are used for roughly the same reason a human-like hand is preferable - human-designed spaces tend to not be perfectly compatible with wheeled locomotion.

      The ability to negotiate stairs is table stakes for a household robot. It's already a pain when one's Roomba-like is defeated by a small ledge...

  • jjk166 5 hours ago

    Well we aren't all wearing mecha-claws to improve upon our feeble human design.

  • mandeepj 7 hours ago

    You can make it switchable! Think of it more like a dye, if that helps.

  • numpad0 7 hours ago

    Why should not we build robots that mimic us?

schainks 5 hours ago

I swear I've seen this before somewhere..

ImPostingOnHN 9 hours ago

Looks like this product is called AmazingHand (and there are billions of "hand"s in the world), so the title might have some room for improvement as far as searchability goes.