[HN Gopher] Artificial muscles robotic arm with full range of mo...
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Artificial muscles robotic arm with full range of motion [video]
Author : janpot
Score : 221 points
Date : 2021-10-20 15:27 UTC (2 days ago)
(HTM) web link (www.youtube.com)
(TXT) w3m dump (www.youtube.com)
| causi wrote:
| "With" needs to be removed from the submission title, as that
| isn't the title nor the intended meaning of the Youtube video
| title. The title is _Artificial Muscles Robotic Arm Full Range of
| Motion + Static Strength Test_ , as in it is demonstrating the
| range of motion of the artificial arm, not claiming it has the
| full range of motion of a human arm. It does not, as clearly
| stated in the video description.
|
| _Fingers are going to move from left to right but they don 't
| have muscles yet. Metacarpal and left-to-right wrist movement are
| also blocked._
| gremloni wrote:
| I can't wait for these things to be covered in real lab grown
| human skin and tissue and kept alive by nutrient packs held in
| the prosthetic itself. That way it doesn't use any resources from
| the prosthetics wearer and we don't have to deal with immunity
| issues.
| rpmisms wrote:
| This has been tossed around as a theoretical for a long time, and
| it looks fantastic. Hopefully we can optimize this and move
| towards full biological integration. Amputees shouldn't have to
| deal with clumsy prosthetics.
|
| Edit: I am curious about what tech would be needed to bring this
| up to near par with a human arm.
| hrgiger wrote:
| First come to my mind Cellink has 3D tissue printers. Some of
| their products also supports soft robotics . I think they are
| not alone in the market.
| throwawaysea wrote:
| Wow that is an amazing demo, mainly because of how clean and
| contained the forearm is. I am not sure what the external
| hydraulic source is like (size, efficiency, etc) and of course a
| mechanical design like this isn't self-healing the way a
| biological arm is, but still pretty cool to see.
| mbrumlow wrote:
| Yah. But it also bleed out or really care if it losses a limb.
| Just needs another buddie to attach a new one.
| zakary wrote:
| This guy is a great engineer, I've been following his stuff for a
| while now. But there are unfortunately several fundamental limits
| which mean this type of system will likely never reach human
| level performance in a real world system.
|
| I work in robotics, specifically compliant and modular actuators,
| similar to the ones in the video.
|
| As I see it, (and many others in the field) One of the biggest
| issues in robotics is a lack of good artificial muscles. The need
| for them is that in a robot which can work with people you want
| it to have both high enough force output and power density to
| actually move things, but you also want the robots arms to be
| back drivable; you want to be able to move its arms by an outside
| force. For welding robots you want the opposite, zero backdriving
| and zero backlash.
|
| To get back-drivability, good torque and reasonable power
| density, you generally can't use spinning electric motors. You
| need to hear them too much. This is why Boston dynamics use
| hydraulics. It's also why Boston dynamics is unlikely to ever
| sell you an Atlas in its current form because those custom
| hydraulic actuators make the system so unreliable and expensive,
| even a mining or gas company would struggle to justify it.
|
| The short and long of it is this: if you want a robot that can do
| the things humans can do, like play soccer and rock climbing and
| knitting, then you need muscles like humans have.
|
| So you need artificial muscles. There are a lot of different ways
| of making them. [1] the issue is no published technology is able
| to give you want you need to make a good analogue of human
| muscles.
|
| The muscles in the video are (correct me if I'm wrong) soft
| fluidic actuators. These actually have pretty good potential,
| especially compared to things like piezoelectric actuators. But
| when taking into account how you would actually put these in a
| real world robot, problems arise.
|
| But the main downside is you need lots of pumps and tubing to
| make it work, and it has limited maximum stress and relatively
| low actuation bandwidth. In a nut shell, to make these strong
| enough to do much useful work, you need them to be really big,
| and that means they can't move very fast. There is a reason you
| don't see any commercially available robots with this kind of
| actuator.
|
| I really hope this creator can make his system do what he has set
| out to achieve. And perhaps he will be the one to figure out a
| new kind of actuator which does tick all the right boxes.
|
| Conflict of interest: The startup I work at is developing a
| commercial product using a new kind of artificial muscle. So my
| views may be coloured by that.
|
| [1] See this paper for a good breakdown of artificial muscles:
| https://sci-hub.se/downloads/2019-10-12/7c/zhang2019.pdf?ran...
| arturventura wrote:
| Hey, I've been looking into artifical muscles myself. Are you
| guys stealth or can you talk about your company?
| zakary wrote:
| Yes we're in stealth, so there is little to be said on
| details.
|
| I can say that I'm a big fan of K. Eric Drexlers work and
| that you should read it if you want to know what the future
| will look like.
| conjectures wrote:
| This and op is all wholesome content.
|
| On the criticism, do you think more limited / lab-bound systems
| will help develop control technology in advance of better
| muscles?
| zakary wrote:
| Short answer: yes.
|
| Long answer: I think that the more minds there are working on
| this (or any other interesting) problem, the more progress
| will be made. And we shouldn't let the perfect be the enemy
| of the good enough.
|
| The field of robotics, and especially soft robotics like
| this, is so new and uncharted that individuals tinkering in
| their garage can and have made real advances for the field.
|
| That said, really good control systems for these kinds of
| actuators are something very much lacking. The human nervous
| system, and in particular the vestibular system is so
| absurdly effective, efficient and complex all at the same
| time that it boggles my mind. Nothing anyone has ever
| designed has ever come close to that level of functionality.
| But to make a robot that can do human things, we need that
| level of functionality. We need to have really good
| proprioception which is integrated with force and feedback
| sensing.
|
| To give an example; open a bag of potato chips and pull out a
| decent handful. Now eat the chips one by one out of your hand
| without dropping any and without using your other hand. I
| dare say you can probably do this, and without crushing the
| chips in your hand. You can feel just how much force to
| apply, you can feel where to place your fingers so that all
| the chips are held just so. You can make subtle adjustments
| after each chip is taken away.
|
| There is no robot hand in the world that can do that simple
| task. Ask any arm amputee. And to get to that point, a lot of
| really difficult stuff has to be invented and worked out. I
| suspect this is a problem which will be solved piecemeal,
| over time, but much of the fundamental work in things like
| the mathematics of motion control, material science and
| compliant mechanisms will come from very well funded labs. If
| I had to guess, I give a 60% chance a robot can do the chip
| eating task within a 5 years. And 85% within 10 years.
| (Especially if the work of my team pays off)
| fstrthnscnd wrote:
| > There is no robot hand in the world that can do that
| simple task.
|
| Is the technology dealing with interfacing with the brain
| good enough, even if on the arm side it's not?
| naasking wrote:
| > In a nut shell, to make these strong enough to do much useful
| work, you need them to be really big, and that means they can't
| move very fast.
|
| Strength is additive. Why can't you just add more smaller
| muscle fibers that work in concert? That's basically how real
| muscles work. This seems so obvious there must be something
| wrong with the idea.
| zakary wrote:
| > Why can't you just add more smaller muscle fibers that work
| in concert?
|
| Great question. And yes, you can have lots of smaller ones to
| do the work of a few larger ones. The strength (stress) comes
| essentially from the cross sectional area of the muscle (or
| bundle of). And no matter how thin you make the spaghetti,
| you still need an equivalent volume of it to get the same
| cross section, For a given length.
|
| The reason speed, as in how many times a second you can make
| it contract and lengthen, is a limiting factor comes down to
| good old force = mass x acceleration. Want to make it go
| faster?then you need higher pressure. So now You have a lot
| of water you need to move at high pressure with very rapid
| acceleration. This means the scale of the pumping equipment
| gets prohibitive very rapidly.
|
| Real muscles work at a fundamental level by a kind of
| ratcheting mechanism between proteins that pull each other
| together. This process can happen very quickly. Mammal
| muscles don't need to pump lots of liquids around with high
| acceleration and velocity. So there is actually a lot less
| inertia from moving mass in real muscle.
|
| Another issue I didn't touch on in my earlier post is that
| this kind of muscle is very difficult to do strain and force
| sensing with. To make motion with this kind of actuator that
| is both rapid and smooth is extremely difficult and still an
| open problem.
| edumucelli wrote:
| Do you remember that Terminator 2 scene where Arnold cut his own
| skin to show the underlying robotic arm? This video seems like
| the "behind the scenes", but for real.
| aaaaaaaaaaab wrote:
| >forearm with hand [weighs] only 1 kg
|
| * without the power source and pumps
| calvinmorrison wrote:
| * cuts arm off *
|
| wow how can you even say this is a human arm? I don't even see
| any power source!
| m0zg wrote:
| For comparison, a decently trained human male can hold
| approximately 80kg (175lb) per hand (350lb total) fairly easily
| without any assists such as straps, and without using hook grip.
| With hook grip or straps, the strength of your back is the
| limiting factor.
|
| That said, as a first step this is very impressive and very
| lifelike, too.
|
| The main issue with this is going to be proprioception more than
| anything - it doesn't seem like you'd be able to do what robots
| do: rely on position encoders. To make this do something for real
| it's going to need a way to know its own position, and feel
| pressure.
| adminscoffee wrote:
| good points, if the system had tension connectors to other
| points on the body than it would be able to increase output. an
| arm using more than what is available in the arm, other parts
| of the body help the strength of an arm. think jiu jitsu and
| types of hits, and their impact
| animal531 wrote:
| I have a really bad back and as a result I can't really
| exercise. So let's say I can carry 8kg max per hand (1/10th).
|
| And yet I'm a fully functional adult human being and can get by
| perfectly fine in life.
|
| So for me from a robotics point of view a much smaller starting
| range is perfect, once you've built it into a platform you can
| start optimizing and increasing potential.
| harperlee wrote:
| I always joke that if I build a robot I will first target a
| very old person that can ask for help in a lot of situations.
| Weak muscles, slow moving, and yet the world will adapt to
| it, seeing that it is fragile and it needs our help for some
| things.
| jjk166 wrote:
| A trained human might be able to deadlift 350lbs under ideal
| circumstances like being in a gym. No one is capable of lifting
| and holding that sort of weight for an extended period of time.
| For an average human under realistic circumstances, lifting
| 100lbs over your head is a difficult task. Lifting much more
| than 50 lbs unassisted frequently in a work environment is
| likely to lead to injury.
| titzer wrote:
| I've watched the video three times and I have my doubts.
|
| Why is the robot arm a right arm and the one manipulating it a
| left arm?
|
| Why is nothing above the elbow shown?
|
| I am not saying this is fake, but it wouldn't be hard to fake. A
| few little zipping noises, some body paint, speed it up slightly,
| add in some CGI muscles underneath the skin...
|
| Again, I'm not saying it _is_ fake, but it could easily be.
| Extraordinary claims require extraordinary evidence.
| alex_duf wrote:
| >Why is the robot arm a right arm and the one manipulating it a
| left arm?
|
| are you asking about the person manipulating it? If so I guess
| that person is just right handed and needs to hold the camera
| somehow...
| tokamak wrote:
| Just check the other videos on the cannel. It gets pretty clear
| it's not a fake because you can see different stages and
| components that make it.
| titzer wrote:
| I did as well, so I don't think it's fake now. It is still
| weird to me that the video uploaded was shot so poorly. The
| OP could use a tripod.
| eagsalazar2 wrote:
| If they worked a little on making those things quieter, they'd be
| like 10X more creepy by virtue of being 10X closer to crossing
| the uncanny valley. When you make a robotic arm that is so
| closely modeled after a human arm, isn't that one of the goals?
| kortex wrote:
| The uncanny valley is wrong. Or rather, it is a result that
| appears due to the juxtaposition of robots with different goal
| criteria.
|
| Turns out, when you focus just on the devices which try to
| replicate both human likeness and emotional relate-ability
| (drop all the WALLe style cute but abstract ones), it's pretty
| linear based on how well that goal of emotional affect is
| achieved.
|
| https://youtu.be/LKJBND_IRdI
| robomartin wrote:
| Well, this technology dates back to the 1950's.
|
| https://en.wikipedia.org/wiki/Pneumatic_artificial_muscles
|
| Hydraulic, rather than pneumatic, operation has also been
| attempted.
|
| Fun stuff, but nowhere close to being practical in any way for
| real world robotics. And, no, it isn't a matter of iterating and
| optimization. These kinds of actuators will never be anywhere
| close to the energy efficiency and technical simplicity necessary
| to build something like a full function humanoid with hundreds of
| actuators that can run without a small power plant connected to
| it via an umbilical cord and everyone in the room wearing hearing
| protection.
|
| That said, it is great to see people experimenting and learning.
| Nothing wrong with that. Great video.
| goldenkey wrote:
| Reusable rockets weren't practical either. But someone was
| maverick enough to attempt it anyways. [1]
|
| You provide valuable information but I just hate how you
| succumb to easy thinking, an appeal to tradition [2]: "well it
| hadn't been done then so it can't possibly be done now." It's a
| form of anachronistic gatekeeping. It doesn't belong in the age
| we currently reside in.
|
| We have totally different computational abilities today,
| powerful beyond reason. Our hardware is smaller and better
| performing. We can perform digital simulations billions of
| times before we even execute one physical experiment.
|
| I've seen the same attitude with age-old mathematics problems
| and it makes even less sense in that domain. The ability to
| perform computational experiments that our predecessors
| couldn't, changes the viability of almost every unsolved
| problem.
|
| Boston Dynamics would have never created Atlas or Spot if they
| clung to common tropes about robots. And now, due to battery
| technology, the once tethered robots are dexterously mobile.
| [2]
|
| [1] https://www.fool.com/investing/2020/10/05/how-much-
| cheaper-a...
|
| [2] https://en.wikipedia.org/wiki/Appeal_to_tradition
|
| [3] https://youtu.be/tF4DML7FIWk
| robomartin wrote:
| > I just hate how you succumb to easy thinking, an appeal to
| tradition
|
| No. I appeal to PHYSICS.
|
| This isn't an emotional argument. Or one out of "tradition".
|
| The reusable rocket was a question of implementation, not
| physics. The math actually supported the idea of being able
| to do that. It wasn't some magical juju bean Musk pulled out
| of his behind. They did the math. The math proved you could
| do it. They built it. It took a lot of trial and error and,
| yes, failure, but they KNEW the math supported the concept.
|
| This inflatable muscle thing (air or fluid) isn't supported
| by the PHYSICS.
|
| What do I know anyhow? I've only been in robotics since the
| early 80's. I have literally seen <insert fantastical claim>
| in robotics and artificial intelligence since that time. And
| here we are, we still don't have a robot of any kind that is
| as capable as a house fly, even with a supercomputer running
| it remotely.
|
| And that, BTW, is the test for fantastical actuators. The
| technology has to support an amazing range in terms of scale.
| At one extreme you have something like an ant and, opposite
| that, an elephant. Even within a human being the range of
| size and strength in muscles is likely 1000 to 1 (haven't
| done the math).
|
| > Boston Dynamics would have never created Atlas or Spot
|
| I don't think you have a good sense of what these machines
| are and are not. Hint: They are not what you think they are.
| goldenkey wrote:
| No, your appeal is to the "cult of science." Science is a
| moving target. Hydraulics involves materials known as
| hydraulic fluid. Material science is in its infancy. Your
| appeal is nothing more than to pessimism and the edifice of
| cocksure.
| cma wrote:
| Reuse has been a goal since the at least 70s, with the
| Shuttle project, Buran, later the DC-X, etc. It wasn't one
| guy maverick enough to attempt it. And it wasn't given up on
| and then revived by one guy. Blue Origin, Armadillo, Scaled
| Composites, etc. were all attempting it. It is the largest
| scale (comparing heavy vs shuttle, though heavy hasn't seen
| much use) and seemingly most successful, and several other
| firsts.
|
| The upper stage still is discarded, but if they can pull off
| the Starshuttle it will be huge and the first operating at
| anywhere near that scale with full reuse.
| zakary wrote:
| It is always good to question assumptions. One you could
| consider is the assumption that all problems are created
| equal. This isn't the case. There are fundamental and
| practical limits to things.
|
| For this kind of artificial muscle actuator, there are
| fundamental limits to the way the physics works for this
| design which prevent it from ever simultaneously having good
| efficiency in energy and power density, high strain and high
| frequency operation. There are certainly ways to make
| artificial muscles work, but hydraulics is not the way.
|
| For rockets and space vehicles, the limit has more to do with
| technology and material science.
| goldenkey wrote:
| Material science is part of hydraulics. The hydraulic fluid
| could end up being next-gen.
| imtiyaz wrote:
| For the first time I have seen something like this. It's an
| amazing demo video.
| feelandcoffee wrote:
| I love how this project looks. Feels closer to Metal Gear Solid 4
| sci-fi bio-tech, than to regular mechanical arms.
|
| Maybe falls a little bit under the uncanny valley but with
| clothes on, I could see this achieving a pretty natural look to a
| prosthetic, plus this type of design seems more analog to an
| actual arm in terms of control.
|
| I know that there is a long way for real-life use, and maybe I'm
| naive because I don't know all the caveats that need to solved to
| make it feasible, but this type of tech gives always puts a smile
| on my face.
| postalrat wrote:
| Why does it sound like servos? With those type of artificial
| muscles I'd expect to maybe hear valves, not servos.
| mikewarot wrote:
| It sounds a lot like there's a compressor driving things in the
| background, and a lot of servo operated valves controlling
| flow.
|
| I bet the "muscles" themselves are quite quiet.
| webmaven wrote:
| I'm pretty sure the sounds you hear (which resemble the sounds
| an articulating-arm desklamp makes) are the 'ligament'
| attachment points and joints.
| verytrivial wrote:
| The motion, form-factor and the range of movements is certainly
| good, but looking at some of the other videos[1] shows the arm
| really is the neat, tiny protuberance of much larger stack of
| technology. The pumps and everything else appear massive and
| bulky. Biological muscles are self-contained, not tethered. This
| is no doubt an impressive demonstration of integration, but
| unless all those pumps are _inside_ the arm, the further claims
| about how this technology will be used seem a bit ... stretched.
|
| [1] https://www.youtube.com/watch?v=-s8YiEBr_u0
| micromacrofoot wrote:
| These things always start off large and gradually get smaller
| (and often miniaturization is where the really interesting
| optimizations come), apparently this apparatus can already fit
| roughly within a human-sized body... which isn't a bad start.
| fho wrote:
| While this definitely is an impressive an impressive one,
| those artificial pneumatic muscles have been around for ages
| [1] but have not become much smaller. My guess would be that
| there is some physical limit on how useful they can be.
|
| [1]
| https://en.wikipedia.org/wiki/Pneumatic_artificial_muscles
| micromacrofoot wrote:
| Physics certainly makes fools of us all.
| Robotbeat wrote:
| Putting the pumps in the torso is a good idea. Putting them
| inside the arm itself increases the inertia of the arm.
| kobalsky wrote:
| you don't have an eureka moment and build a perfectly
| functional android from scratch. this is a necessary step
| towards a better-than-human arm
| arlattimore wrote:
| Impressive range of movement!
| juliusz_t wrote:
| We just start the incorporation process. Our team is looking for
| first clients and investors. We plan to start with the first
| preorder in the coming months.
|
| If interested, please contact us by e-mail:
| automaton.company@gmail.com
| espadrine wrote:
| A few comparisons:
|
| > _forearm with hand [weighs] only 1 kg_
|
| That is slightly below a human forearm with a hand.
|
| > _This artificial muscles robotic arm is operated by water and
| consumes 200W at peak_
|
| The ideal consumption necessary to raise this 7 kg dumbbell by 1
| meter in 1 second is 7 watts.
|
| Human muscle is about 20% efficient, so it probably consumes
| about 35 watts. Almost a tenth the power.
|
| A human arm can also achieve about double the maximum output of
| that robotic arm: for instance this crank[0] offers 400 W max,
| with a more typical 50 W sustained output.
|
| > _achieve human immortallity [sic] by transplanting the brain
| into the machine_
|
| That feels like a stretch, given the complex needs of a brain
| (not just in glucose fed through veins, but also immunity
| protection and so much more). Brain transplant into an organic
| body seems easier, and even that does not address the fact that
| brain cells themselves age.
|
| [0]: https://www.electricpedals.com/hand-crank-generator
| KronisLV wrote:
| > Human muscle is about 20% efficient, so it probably consumes
| about 35 watts. Almost a tenth the power.
|
| Being just an order of magnitude away from biology that took
| millions of years to develop and evolve is really impressive in
| my eyes!
|
| > That feels like a stretch, given the complex needs of a brain
| (not just in glucose fed through veins, but also immunity
| protection and so much more). Brain transplant into an organic
| body seems easier, and even that does not address the fact that
| brain cells themselves age.
|
| That said, this is probably the more reasonable argument.
| Ideally, eventually we'll just find ways to prevent much of the
| cell damage with aging - initially it probably won't lead
| anywhere near "biological immortality" (so it's pretty likely
| that everyone reading this will die and will cease to exist),
| but at the very least it'll lead to better quality of life at
| the more advanced ages and less human suffering overall!
|
| Definitely an area that should have anywhere from 10x-100x the
| resources that have been allotted to it currently. Of course,
| one can also dream about staving off the eventual and
| inescapable clutches of entropy, if that allows them to live
| without existential crises and dread sneaking up on them, as it
| does with me.
|
| Regardless, even advancements in robotics are immensely useful,
| paving way to everything from improving the quality of life for
| those who've suffered accidents, are differently abled in
| various ways, or have other factors that otherwise make their
| lives more challenging.
|
| As for robot transplants or even living transplants, unless you
| can connect back all of the nerve endings that map roughly to
| what the host body needs, it's likely that it'd be like being
| fully paralyzed. In that regard, cryonics would be a better
| bet, to preserve the human being until the medicine has
| advanced to the point where any ailments and such can be
| addressed. Of course, seeing how new and still fledgling (and
| niche) the industry is, it's unlikely that many if any of the
| people will ever actually be successfully revived, much like we
| can't unscramble the brains of mummies in tombs.
|
| But hey, if nothing else, it's an interesting pursuit and the
| trans-humanism movement is always curious to behold. Who
| doesn't enjoy racking their brains, imagining engineering
| solutions to problems that no one would have even considered a
| century ago?
| jaclaz wrote:
| >The ideal consumption necessary to raise this 7 kg dumbbell by
| 1 meter in 1 second is 7 watts.
|
| You sure?
|
| A HP is 75 Kg raised by 1 meter in 1 second (and is roughhy 750
| W): https://en.wikipedia.org/wiki/Horsepower
|
| Raising 1/10th of the weight by same distance in the same time
| should be 1/10th of that i.e. 70-75 W.
| progbits wrote:
| Yeah it is wrong. 68W ideal, assuming pure conversion to
| potential energy with no loss:
|
| https://www.wolframalpha.com/input/?i=7kg*1m*%289.8m%2Fs%5E2.
| ..
| amelius wrote:
| energy = force times distance
|
| force = 7kg times 10N/kg = 70N (roughly)
|
| So yes, more like 70W
| jaclaz wrote:
| Good, so if we take for good the mentioned 20% efficiency
| of human muscles[1], the robotic arm wins largely, as
| 70W/0.2=350 W vs. the declared 200 W of the robotic arm.
|
| (I still doubt that the robotic arm can be almost twice as
| efficient as a human arm, however, so probably the 20% is
| not accurate or there is some other factor involved) .
|
| [1] which I have no idea if correct even roughly
| zzzzzzzza wrote:
| > achieve human immortallity [sic] by transplanting the brain
| into the machine
|
| the intuition is that it's probably easier to figure out how to
| keep a brain alive than an entire body alive
| spacecity1971 wrote:
| Your intuition is correct, and it's already been done:
|
| https://www.nature.com/articles/d41586-019-01216-4
| Aeolun wrote:
| Brain without a body will feel really weird though.
| bserge wrote:
| Yeah, they better connect the "feel" parts to _something_ ,
| otherwise insanity/suicide/murder might ensue.
| maxyurk wrote:
| "... and even achieve human immortallity by transplanting the
| brain into the machine."
| arketyp wrote:
| That entire last sentence came off both naive and quite
| sinister. I'd like to think that if robots are to "serve people
| for fun, as butlers" at least they don't have to look like
| human slaves.
| ecpottinger wrote:
| What I don't see is how much hardware is needed to drive that
| arm.
| juliusz_t wrote:
| We use custom valves, single board computer, water tank, pump
| with controller and a dozen meters of tubing. Valves are not
| shown on purpose.
|
| All these things would fit in a human chest - we have a plastic
| skeleton next to it. We are working on further minimizing this.
| agumonkey wrote:
| you think there's a massive machinery outside the camera frame
| ?
|
| i've seen some wire twisting as motor few years back, maybe
| that's what they use
| [deleted]
| amelius wrote:
| Next: sensory input?
| juliusz_t wrote:
| I am the member of crew responsible for the control system. ;)
|
| We already have encoders in our fingers, however we have delays
| in electronics that will aggregate the data. The next hand
| model will have feedback.
|
| However, the real problem is refining the manufacturing process
| to be repeatable. Too many things are done "by eye" at the
| moment.
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