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Kind: captions Language: en there are robots the size of bees others that can jump on water and some that are powered by tiny combustion engines the size of a penny one day they could work in swarms they could save your life or even spy on you we got access to the best micro robotics labs in the world the flip to learn how these robots work and what are they for this video is sponsored by onshape this is a tiny Yellow Submarine underwater it can move around by flapping these miniature Wings Nine times per second but you can use those same Wings when the submarine is out of the water only now you have to Flap them 250 times a second to make it fly so this robot can do both it can fly and swim but since it weighs only 175 mg about the mass of two Cheerios surface tension is a problem that's a consequence of physics at a smaller scale the surface tension is like a wall that blocks the transition process this happens because water molecules are slightly polar groups of these molecules pull in all directions but at the surface there's no water above so the pull is only sideways and downwards this imbalance creates strong cohesive forces that compress the surface into a tightly packed layer making it difficult to break this is the same effect that lets water striders walk on on the surfaces of ponds and lakes this other robot weighs only 68 mg and by using a spring mechanism that mimics a flea's leg it can jump without breaking the water's surface just like a water Strider it's like there's Solid ground below now that's great if you want to stay on top of the water but this barrier can also be a problem if you want to go underwater to escape this trap the submarine splits water into hydrogen and oxygen and then stores these gases in a buoyancy chamber it does this because the wings are super fragile if they started flapping while the robot was still trapped underwater they would break right off so the buoyancy from the gas helps bring the fragile parts of the robot out of the water but the robot is still stuck in that top layer of surface tension so a sparker in inside the chamber ignites the gas and the explosion breaks the surface tension and shoots the robot 30 cm into the air and once it's free this robot can fly this robot found a different way to break through the surface tension it uses these large water repellent copper pads on its feet to walk on the water but when it needs to dive beneath it applies 600 volts to those pads which creates a positive charge that attracts water molecules to it and breaks the hydrophobic barrier and that allows it to sink on command then once submerged it can walk underwater both of these robots were made by Dr Kevin Chan at MIT we looking at the flight room and this is where we do all of our flight experiment as you can see has motion capture cameras this lab is one of the only places in the world where robots this small attempt flight Okay so because this robot's so small it has such low inertia right so you're saying that it could flip faster than any other drone in the world Beyond 7,000 de per second I mean you can actually hit the button you let me hit the button yeah I'd love to ready yep okay 3 2 one you know who [Laughter] F getting these robots flying is tough I mean they're the size of bees so the internal mechanisms have to be even smaller like the parts of a watch y components have to be precise to within five microns that's a tenth the width of a human hair in the summer we have those very big flies sipping by in the lab and I was making the stain of oh they're just showing off take two 3 2 1 woo yeah that fli go I [Music] got so these Bots fly but not like birds I mean they don't soar instead they have to use a whole lot more energy flapping their wings hundreds of times per second so why do they do that well it comes down to this scale phenomenon larger objects typically have less surface area relative to their volume and that's important let's just approximate a flyer by a cube let's say it's 10 cm on a side well then that would have a volume of 10 x 10 x 10 or 1,000 cubic cm and it would have an area of 10x 10x 6 sides 600 square cm so the surface area to volume ratio would be 6: 1 but now imagine we have a much smaller flyer that is just one cubic cm in volume well its surface area is going to be 1X 1 * 6 that is 6 square cm so that's going to be 10 times the surface area to volume ratio it's going to have a surface area to volume ratio of 6 to 1 now why is that so important well it's because drag depends on surface area so if you have more surface area to volume well you're going to have a lot more drag and also at that small scale you'll be much lighter relative to that drag so you're not going to have as much inertia so you'll get pushed around more by the air so you can't just soar through it like a bird and that's why bees and other insects flap their wings a lot what they're doing is generating swirls of air above the top of the wing and those vortices create low pressure zones when combined with a high pressure below the wing that is what generates lift so they're pushed up into that low pressure region by flapping their wings back and forth this robot was inspired by seeds from a maple tree their unique shape creates the same swirling vortices above the seeds Leading Edge and as they fall they spin and generate surprisingly high lift these seeds are still just falling but if you add miniature electric rotors to the ends of each wing tip on this robot then it can generate enough lift to [Music] fly but this robot isn't quite insect scale it actually weighs about 50 times more than the robo bees in Kevin's lab so to power something that small you can't just use electric motors I mean the magnets and coils don't scale down effectively to such a small size so to to power the first robab bees they had wings driven by special crystals called pel electric crystals by applying a voltage across the crystal they contract slightly but only around. 1% not nearly enough of a deflection to make a robot fly so roboticist designed a chassis that mechanically amplifies the motion 30 times if you then turn the voltage on and off 120 times per second the robo be flaps its wings and flies [Music] but there is a downside to piso electric crystals which is they're fragile even a small impact to the wings and the Crystal cracks and the robo be stops working so at MIT they are building their Robo bees differently they're so confident that it will survive being dropped that they're going to let me throw it off of a building so I mean here we go okay we got to go see come on [Music] I mean it looks pretty good this is amazing like H how does this thing survive I have no idea well these robots have a secret ingredient so put it scale zero it instead of using pisos to drive the wings these bees use soft polymers they effectively work like tiny muscles let's drop it here they take a polymer and they coat each side with carbon Nano tubes that creates two effective conducting plates so if you apply opposite charges to these plates that pulls them together stretching out the polymer but if like charges are applied to both plates they repel and so the polymer shrinks and if we roll up layers like this into a tube we can amplify the force they generate it stretches up to 25% of its length by cycling the voltage hundreds of times per second these muscles Drive the robo's wi when you shrink down to smaller scale your flapping frequency goes up higher so we at the 400 HZ range just a right in between a honey bee and a mosquito yes this flexible muscle can take bumps and scrapes and keep working but if it's pierced by a needle the carbon nanot tubes get pulled in and then the plates touch causing a short circuit that renders the muscle useless but the scientists have even found a way around this when high current is cycled the carbon nanot tubes that are touching burn off and so the muscle self-heals Kevin and his team even invented a process to perform laser surgery on the robot you're creating smaller defect around a very very big defect and then by isolating the small defect you're using the small defect to isolate the big defect so that was what we call the laser assisted clearing process one robot was really tested to its limits its artificial muscle muscle was pierced by Cactus needles and hit by a laser beam and it could still fly but these muscles are energy intensive and for robots at this scale that have to be so light there's no room for extra batteries luckily there is another way to get around that's a jumping flying robot this Robo be conserves energy by hopping this Tech was used on another drone at the City University of Hong Kong normally this drone can only fly continuously for 6.3 minutes but with the hopping attachment it can keep moving for 50 minutes nearly 10 times [Music] longer scientists believe this could be even more effective in Low Gravity low air resistance environments like Mars so it would be perfect for an Ingenuity version 2.0 but Micro robots are already being used today every day planes complete hundreds of thousand thousand of flights and most of them have multiple turbine engines now a crack in a turbine can be catastrophic so manufacturers inspect them every 3,000 flight Cycles or 180 days but inspections cost tens of thousands of dollars and can take a whole day that's where this cockroach inspired robot from earlier Hammer comes in it's incredibly fast it can run 10.5 body lengths per second speaking in relative terms that's faster than a horse and and it's versatile its special foot pads can apply a voltage to polarized metal surfaces creating an opposite charge underneath its feet and that's how it's able to stick to metal surfaces similar to a balloon sticking to a wall after you rub it on your hair Rolls-Royce and Harvard are working to put Hammer inside of engines to inspect for Turbine cracks even upside down and since its mass is so small adhesion forces are much stronger relative to its weight so hammer can get into some tight spaces and that can be pretty useful one of the first times that robots were deployed in an emergency situation was during the 9/11 search for survivors at Ground Zero Unfortunately they didn't turn out to be that helpful they were big and expensive and they'd get stuck three different types inspected eight sections of Rebel but none found survivors so an ideal rescue robot should be able to navigate tight spaces with stand damage and debris operate across varied environments and be inexpensive enough to be replaced if destroyed the material cost is actually quite low for making the robot the the the human labor is high but in terms of the material couple of dollars per robot it's really enough yeah right yes so the idea is to deploy swarms of insect sized microbots to search for survivors in disaster zones [Music] but I understand when I say swarm you might get a little worried I mean swarms of miniature Killer Robots are straight out of dystopian sci-fi think the hunter Seeker from Dune or the killer robot bees from Black Mirror you might be familiar with that like famous black mirror TV episode where all like the bees yeah when that came out everybody that I had ever met in my entire life sent me a text message it was like hey bro you seen this but this idea isn't so farfetched in the early 2000s bees were dying off it's called colony collapse disorder Congress is holding hearings even the vice president has been briefed in fact the whole Robo be project started with the goal of replacing the bees thankfully that idea didn't last long bees can do much better jobs in terms of pollination than those robot much more cheaply to pollinate you need a huge colony of Beast to do those effectively also from an Environmental Protection perspective I think it doesn't make sense to replace bees with robotics bees from a cost effective perspective and also from the perspective of you know if you have so much money why why making those bees and protecting the real bees okay so they won't replace the bees but I can still easily imagine a world where these same robots that are supposed to help in a disaster are secretly being used to spy on me I mean it's a bug that would literally look like a bug that's terrifying is there any fear from you about what they could be used for like ethically we really focus on the fundamental science and solving the fun technical problems and as a society in general we all should think about collectively how to prevent those new technology from doing harm but we're getting a bit ahead of ourselves I mean most of the robots we've seen aren't able to spy on us in fact they're not even fully autonomous we have offboard uh sens from those cameras you have outboard power from those and outboard computation what what you see today is everything is offboard hopefully in 5 years then we can combine both sensing autonomy and power autonomy and that's the longer term goal Harvard's Robo be has managed short bursts of untethered autonomous flight so it's fair to say we aren't that far off from robot insects operating freely around us still there is a limit to how far these robots can go on just batteries batteries need shielding to prevent damage short circuits and leaks and the thing is as batteries are scaled down this shielding has to stay about the same thickness so that means smaller batteries become increasingly inefficient and that's ignoring that the energy to weight ratio of batteries is just fundamentally lower than that of chemical fuels at the insect scale every milligram matters we just said like let's just sail past all of that and just use a a video game cheat code and and just power our robot with the smallest explosions possible and put two tiny internal combustion engines on board it and it works and it sounds like a combustion engine which is probably the my favorite part of it Cameron's Penny sized engine runs on a constant stream of methane and oxygen this is fed into a chamber where it's ignited by a spark and so it combusts releasing a burst of energy the hot gases rapidly expand pushing against a flexible polymer membrane that acts like a piston so the membrane moves as the piston and then instead of having to like have any sort of elaborate system that brings it back down because it just naturally is elastic it it sort of has its own restoring force that was our our clever little Innovation as the membrane shrinks back it vents the exhaust gases allowing the cycle to repeat despite the continuous flow of methane and oxygen the fuel Co line never catches fire that's because as explosions get smaller their volume shrinks much faster than their surface area this causes them to lose heat more quickly to their surroundings in Cameron's robot only a small amount of gas Burns at a time so heat quickly escapes into the fuel line cooling the gas and stopping the flame from traveling back up the line with just two of these combustion Chambers on a little robot one for the front legs and one for the back Cameron can control its heading you can actuate just one of the two sides at a given time if you want because both sides are operational so if we spark in both sides it'll move straight but if we just do one or the other it'll pivot and this robot is super powerful for its size it weighs 1.6 G which is about as much as a gummy bear weighs it can jump like 2 fet in the air approximately it can carry 22 times its body weight which is about what a cockroach or a lot of beetles can do we'll be able to put a fuel tank you know uh micro Electronics sensors a camera battery and still have weight left over to go and and this thing will still chug along that's the future that's the goal scientists have created robots that can do what some insects do and there are clear applications for this work but for these roboticists these self-labeled Misfits that's not what it's all about if it's about application we should all like make a startup and try to like think about what we can do to make money right we think there are nice applications like inspection and search and rescue but I would say as a research lab we are mostly driven by curiosity I that's a very honest answer so cool if you are someone who designs Hardware like these robots mini or Mighty you know that you need to create a cad model first so you can prototype and bring your ideas to life but the problem with most mainstream CAD software is you need a very powerful computer and a mighty budget that's why we reached out to today's sponsor onshape onshape is a modern Cad and PDM system designed for businesses and unlike any other professional CAD system on shape is built entirely in the cloud powered by Amazon web services that means you don't need expensive computer hardware it never crashes and you never lose your work it just runs in your browser on any system be it Windows Mac Linux or even on your phone I can actually pull up that mini robot model right now and start moving some of these things around it's also built to be collaborative so you can work alongside friends or colleagues like never before on the same design in real time for businesses you can trial on shape for 6 months and for students hobbyists it's completely free to use just head over to onshape dopro veritasium and sign up to to get started today on shape also uses tried and tested git Style version control methods from software design so you don't have to worry about sending multiple large files around and keeping track of all the different iterations it is all done for you none of this emailing V2 final final for real this time one nonsense if you work for a government agency or have contracts with the government I have good news onshape now has a plan that enables teams to comply with Federal Regulations like itar and ear so nothing is holding you back go sign up for free at onshape dopro veritasium to get started engineering for the future today I want to thank on shape for sponsoring this video and I want to thank you for watching so cool
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