As a physics grad, I just want to commend you on making understanding physics accessible to many people with very little oversimplifying. This is one of your best videos for sure.
@TheDofflin Could a Gyro be used to generate electricity? Like, could you use rotation (and the resulting increase in speed) to drive a shaft, kinda like a steam turbine? Or by using magnets on the rotating part, like an electromagnetic dynamo?
I've wondered about these balls for years (decades maybe?). I always assumed there was something about precession that I didn't understand, which allowed the work to be backfed into increased RPM. Turns out it's actually about the shaft rolling along those races in the ball. Man, this was like pulling a splinter that's been stuck in my brain since I first playd with one of those things. Thank you!
As soon as I got one I couldn't stop thinking about it until I figured it out. I wanted to just believe in the math and say it all worked out somehow, but it feels so much better to actually understand the mechanism!
@@TheActionLab ...But do you really understand that friction? Can you build smaller ones, all the way up to bigger ones, and use the motion of robots to harvest the full energy of footfalls, jumps, shock absorbers, etc.? (If you could that would have interesting applications for robots and drones, right?) (And what about a drone that stabs a telescoping ultra-light-weight rod into the ground, then uses gravity plus a bike-chain+friction+"races" to get the gyroscope spinning, along with magnets passing over copper plates+coils to regenerate battery electricity?) The drone could slowly slide down the rod, which would be geared with a small gear running to a much larger gear, so a small downward motion harvests the maximum energy from gravity...like the gravity LED camping lights being used in Africa where no electricity/light exists.
There's no channel that consistently surprises me nearly as much as this does. There's always something new - to me - in every video. Either it's the thing being demonstrated, like this video, or a surprising result of an experiment, or a really intuitive explanation of a phenomenon I'd seen for years. It's the beauty of science - and the world in general - that there's always something to learn, and this is a great place to come for just that.
I remember reading about a practical joke, Perhaps done on "Candid Camera" where they placed a gyroscope on a briefcase with lots of sound insulation and asked people to carry it to another office. The briefcase kept trying to point away from the intended direction and it was a s if a ghost was trying to wrestle it away. The victims tended to become quite alarmed.
I just bought one from Amazon and I can say that whoever came up with the idea of designing a gyroscope which can be used as an exercise/fidget toy is absolutely ingenious. Big 👍🏻 thumbs up to Physics.
I remember applying WD40 in an attempt to make one of these to go faster. I ended up with a floppy powerball that wouldn't accelerate and it was ruined. This explains it.
The only correction to your description is that both ends of the axle contact opposite surfaces when it is twisted, thus, both contribute to increasing spin. The best motion is that of a wobble plate. You keep the axis ahead of the downward movement which causes it to pivot, the pivot causes it to push up maintaining pressure against the downward movement. The combination of the pivot and upward pressure create enough friction to accelerate the axle and the attached rotor. It only reverses pivot direction if you get ahead of the axle.
Exactly! This is what people without fine motor skills don't get... Also you don't get that horrible clicking/banging sound of the axle constantly having to change its friction surface, which can't be good for the overall lifetime of the plastics in particular.
I had to smile watching this. We've been selling Powerball worldwide since 1998 and have often been asked for the science behind the concept. You nailed it nicely here, thank you. Our customers also often make the mistake of oiling their Powerball in the hope that it'll make the rotor spin faster...a big no-no as you've demonstrated here. All is not lost if you've done so however; TWO deep cleans of all internal components with isopropyl alcohol (while holding the parts with tissue paper to avoid any further contamination with natural hand/finger oil) will do the trick and restore the natural friction once again (two full cleans mind...once isn't enough if you've oiled any part of the internals). Opening the ball can also be done by pressing down on the shell around its circumference while supported by a hard surface such as to flex the two halves which causes them to 'pop' apart instead of using a screwdriver which may damage the plastic.. Hope this helps and thanks again for the content, regards, Rory
I hardly ever comment on your videos, but I wanted say thank you for making them. They have generally been very informative and you make it fun to learn about these topics.
PhD in physics here and was sort of wondering about these toys for years, loved to use them, never quite got curious enough to research it myself (weirdly enough)... That was great. 🙂👍🏼 Really tied some loose ends. Thx 🙏🏼
As a beginning rock climber and recently just coming across these interesting forearm work tools this video was awesome!!! Now I can go to the rock climbing gym and when I see them totally understand what’s going on! Love your content keep it up!
Love these devices. Got my first one back in late 70s. Once you get the feel, you can sense the position of the axis and move accordingly. A bit like surfing a wave.
I got my first powerball (that's what they were called back then) about 15 years ago and i remember getting sore forearms after excessively playing with it the first few days. I also was interested how they work and noticed friction is a big part of it, because I ruined one, by slightly lubricating the running surface of the axle, and on the topic of skill, well i would slightly disagree. I've seen lots of people fail to get it going, because they were not able to feel the movement, once the rotor reaches a certain speed, you can feel the force and basically push it around in a circle slowly increasing the speed. Just wiggling your hand uncontrollably usually ends up stalling the ball.
That's what happened to my one - thought I would give it a squirt of wd40 to make it go faster and yep you know what happened!! Great video thank you for sharing.
well i think if you would have put it at the right spot it would work. You've got to only put it at these 2 rubber circles or remove them. Then it will go insane i think
10:23 A small error: The thin metal axis touches at both sides. But one end touches the upper shell and one end touches the other shell. So both ends roll clockwise or counterclockwise together. Nice video! Can you please show us the generator for the LED and the starter mechanism with the spring.
I just learned precession in physics about one or two months ago and completely failed but this genuinely makes a lot of sense, especially with how you explain it with so little incomprehensible math
I wish you were a school teacher for people everywhere. Always interesting stuff, always explaining things in a way most people can understand. The world could really use more people like you
I've been using those since the 70's, they work well. The first one I had was called a Dyna-Bee. You can hold your arm in different positions to work different muscle groups.
They're this old? I thought it was a late 90s thing. They were called Powerballs at that point, which makes it confusing to google, because of the Powerball lottery.
@@krzysztofczarnecki8238 The selling point for it in the 70's was. The shell was made of the same material as the Astronaut visors because the moon visit was just 6 years prior. I have one from the 90's and a newer one from the 2010's. They do work. Try different arm positions, you'll feel it.
Hats off to you. I’ve been wondering about this for decades. I’m still convinced there’s a way to extract energy from the earth’s rotation using exactly this method.
I got one of these back in 2018. A string pull one. You can start it with a quick flick of a thumb, too, with practice. Was surprised how much of a workout it is for the forearm. Good physiotherapy for people with grip issues :)
@@robertmckeown5315 WOAH COOL i didnt know they were around back then!!!! the first powerball i had was amber colored too, what was the inside ball's color?
BOTH ends are touching the groove at the same time, but on OPPOSITE SIDES. If that were not true, there would be a translational force on the rotor. When you reverse the torque on the ball, the rotor ends reverse sides they contact to. There are 4 possible places of frictional contact (2 shaft ends, 2 sides of the groove they can contact). This is in effect a full-wave rectifier, the 4 possible contact points forming a bridge rectifier, continuing to accelerate the rotor despite reversing the ball rotation. More effective rotor driving occurs if you orbit the ball in a circle (versus simple alternating rotation).
For those who don't use these a lot, swinging your wrist back and forth isn't the best\easiest way to use these. Everything about the ball is circular. If you swing it back and forth, you'll hurt your wrist. Rotate it like you're drawing circles on paper and you'll avoid joint damage or pain. Nice video! Never knew that's how they worked and I've been using them for decades.
When i had my first summer job at a warehouse, i would get on the pallet jack one leg on each side and start turning the handle left and right, and that side to side movement would turn into forward movement, and i could make it go really fast, the whole thing was so intuitive. Dont try this, but in case you have to stop, turn the handle all the way to either side VERY fast and the front wheel would act as the brake.
wow, I had a gyroscopica exercise ball too when I was a child. I can't believe I'm seeing it again in TH-cam and also found out that it has a way longer history than I thought (from the 70s) 😅
Funnily enough I had one of these and some of my coworkers wasn't able to keep it moving. Regarding the mechanics I suspected a little bit of how it works but this is great to learn all the small details. Great video as always!
I have a few of them and had the same experience. Various people can not get the smoothness required to get them to a fast enough rpm that they overcome an occasional stumble. I found if I got it going *really* fast, and handed it to them (easier said than done as that sometimes results in fingers going on the exposed part) they could *keep* it going, and get a feel for the motion, which sometimes resulted in them being able to figure out how to get it going in the first place. Mine do not have the fancy spring mechanism though, and instead have a cord that you wrap around the ball then use as a ripcord to get them going. One has lights, one has holes that make it scream like a banshee (oddly i don't use that one hardly at all, even compared to the minimal amount I use the other)
I've been using one of these to exercise forearms, glad to finally understand the physics behind it! Thank you for creating this video as always, amazing stuff!!!!
I remember having that gyro ball back in 2008, they were called powerballs, my friend had a "speed meter" on it, and we (not me) reached over 20k rpm :)
That's a really nice score. My best was 13,429, I still have a photo I sent in to their leaderboards on this computer. I remember one guy dominated the rankings and could top 20k easily with both hands, at the same time.
I used to play with one of these when I was a little child, but it's so long ago that I had already forgotten.. until I saw it in your video and remembered. Now I want one again!
I just tried mine that i haven't used in years. It starts up with a string wound around the gyro. Put a piece of reflective tape and meassured the RPM to 8000 at the fastest i could get it to spin. I'd get a bit worried if i had a ball spinning at 10k rpm in my hand held together by plastic.
I used to have one of those - it had a string start and could get it going mad fast! Don't know how many rpm though but must be thousands probably 4 or 5
PowerBall perhaps? I had a blue and transparent PowerBall, with a tiny screen and a string. Spring loaded makes so much more sense, yet I could get the ball spinning crazy fast with the string and then just go even faster. Yay physics!
Crazy informative! I instinctively understood it because mine got dirty, and the friction increased to the point where the ball would not move freely anymore to the point that it became unusable. But now that I know you can open them up, I’m going to buy another one and get back to it! Thanks for the video!
dude this was a great explanation. i got one of these gyros years ago and could never figure out why it increased in acceleration. I remember the instructions explicitly stated not to lube any part of the gyro just keep it clean. Thank you for this great video.
Fun fact: I had one of these, and noticed how gritty the procession axis was, I proceeded to put 3 in 1 oil on the outer ring which rendered the toy useless. These little things are really cool.
I had one of these years ago, I came to the same conclusion and also ruined one of these the same way by lubricating the bearing. For anyone who wants a gyroscope toy, these are really neat, the feeling of fighting a gyroscope is really strange.
it works because the outter shell allows the gyro to slip in either direction... so .. what pumps the rpms is the constructive interference of your movements... or the inner and outter rotation..ie the movments you make in relation to the spinning gyrocope - you are in control of the outter shell( constructive interefrence is only possible in phi ratios)..once u get it moving fast ( high rpms) grip it with your hand like you want to crush it... you will feel your skeleton vibrate .. and all the muscles up the chain from your hand to your shoulder to your lats turn on.. from here it doesnt take much movement to keep it moving.. more strength to control the tiny movements..... it is used as rehab for gymnast and such... it is tendon/ ligament conditioning
if u get a hold of an older model.. one that has the string start.. instead of the crank spring.. and learn to start it without using the string .. manual ..and then controlled rotation to get it slowly moving ( prettty hard). u will learn more about how it works intuitively...
if you want to know the speed of rotation, you can match the sound to an app like “sonic” and the sound frequency (lowest harmonic) equals the spinny rate. your ears are good sensors.
There is a device called the sea keeper, same overall gyroscopic idea but to stabilize the boat. I'm very curious what would happen if someone put a sea keeper gyro in an offroad truck. I think it would eliminate nose diving and make out stable in a sharp turn instead of rolling on two wheels.
Interesting idea. If it was powered and gimbaled it might work. Imagine rock crawling Jeeps climbing higher because they have a controllable center of gravity…. with gyros. Just don’t lose power to your gyros in a high place or you’ll crash. I know higher tech gyros are powered and encased in a housing under vacuum for high speed rotations… this is where air bearings or actively lubricated bearings help to keep the rotational speed up and the wear down… Just food for thought..
Well, a sea keeper relies on the following: most boats are much longer than they are wide, so only suppression of rolling is required. The sea keeper gyro uses the stability of the ship against pitching motion as source of leverage to counteract rolling motion. So: if the sea vessel would be some sort of circular raft the sea keeper system would not have the leverage it needs. On an offroad truck you would need both capabilities: suppression of hard pitching motion and suppression of rolling motion. (But only very rarely both types of suppression at the same time.) That would require a much more complicated system than what suffices for a sea keeper. If for offroad trucks computerized stabilization is possible at all I expect it would have to consist of an onboard computer taking in video of the ground, processing the input, and with the computer anticipating what is coming up actively moving the suspension to match the profile of the ground as much as possible.
@@cleon_teunissen Or accelerometers and pitch/roll sensors feeding a programmable/tunable computer that puts out signals to servos on the gimbals and gyro speed control….. less complicated than video to cpu processing with more off the self parts. Maybe even have the gyro/gimbal assembly on a geared rack on a sliding track to accentuate pitch even more for forward/reverse climbing? At that point weight and complexity grows. Rock crawling is usually slow unless it’s King Of The Hammers type racing… I guess speed of climb and maneuver would dictate type of system. You idea is better for high speed because the suspension is responding before the obstacle in anticipation rather than reacting. I guess at what point does the stability system sacrifice durability/serviceability in the middle of nowhere? At what point does it become a robot that a trail rig? Interesting idea. 🤷🏻♂️
Seeing a video from this channel on these devices makes me happy. One of my high school classmates brought one of those in back in the late 90's before they were available because his uncle invented them and sent him one to test out. It didn't have the spring start, though. It was a pain to get going.
That was fascinating. Had me wondering just how in the world that worked all the way up until almost the end when you explained the friction. I was thinking it was some complex physics to do with it changing directions but being held in one spot or something like that. Now I want to get one. Not really to exercise with but just to play with haha
The device has 3 axis of momentum. If you add resistance to the second and power to the third, the first one gains incredible momentum. Fascinating. I wonder if this applies to rotating magnetic fields too..
If you «spin» your wrist you get a smooth motion, avoiding that harsh knocking. You can also change which way the ball rotates at full speed by spinning your wrist the other way
For a more comprehensive exercise, try to picture a laser coming out of the center of the ball int he direction away from the palm of your hand, and try to draw circles on the ceiling, floor, or wall with the laser.
I had a Dyna-Bee blow up when I had it revved up. It made quite a loud noise and blew shrapnel out, but the shell protected my hand. It was really fortunate that a nearby child was not in the blast zone. The rotor material looked like a composite of fine particles like clay that broke into many pieces.
If that was one of the plastic-overmolded ones, I think the rotor core was zinc. Obviously a defective rotor in your case, though. There's a thing about zinc, where if it is contaminated with lead, this causes "zinc rot" or "zinc pest", which causes the zinc to crumble. Could be that's what happened to it.
@@BrightBlueJim Interesting about the zinc cores. I am pretty sure it did not have a plastic coating on the rotor. I remember thinking it was way too dangerous the way it was. It mIght have been one the earlier ones.
Great video! Just a little bit of info on the gyro ball, the tiny groove that the axle sits in. As you change the angular momentum by rotating your wrist either clockwise or counter clockwise you can change the direction of the spin. Also, as you rotate your wrist you are causing the axel to run on the top of the groove on one side and the other side of the axle to run on the bottom of the groove. So as you slowly increase wrist rotation the end result is faster gyro rotation! Ps . Where did you get the regular gyro? Again thanks for the great videos!
I was looking for specifically this comment - I felt he missed the point that one axle rides on the top lip and the other on the bottom when you're accelerating. Then the rotation of the spinning gyro can stop when you stop tilting the device. Interestingly, the races can become pitted if you allow this to happen too much at high RPM. A lat point to understand is that the nylon harness ring holds the ends of the axle just so the gyro won't run off in one direction and rub against the inside of the shell when it's spinning in place (ideally only upon startup or at low RPM).
First time I used one of those when I was a kid, I played with it all day & caused my forearms to be so overworked they locked up & I couldn't use my hands the next day. Fun to play with, just be aware it IS working out your muscles even if it doesn't seem like it.
I have couple of them, the ones called "powerball", with included rpm counter, my record is around 13k rpm. There was a model of powerball that included several magnets on it's rotor, and an attachment meant to generate power to even charge phones!! Really cool gadgets, but just one drop and it's ruined because it gets out of balance, noisy and vibrating machines.
I had one back when they were called "Powerballs" and everyone around me had one. Recently I got another one that has the spring so there's no need to use a cord like the old one. The thing is, it's not just twisting your wrist, you need to get a feel and "help" the rotor by syncing to it. If you do it correctly, you'll feel it and it will easily spin faster, otherwise it will start making loud noises as the rotor is fighting against your timing.
😎 i got one of those when they first came out, back in the early 70s, a little primitive compared to this one with the built in starter and the addition of the lights. They originally were called 'DynaBees', 'dynamic' and they sound a little like bees, more a hum really, goes up in pitch with increasing speed. Still have the old one, durable goods. Mine, you have to start by rolling it on a surface or spin it with a thumb. That can be an art in itself, does take a little practice. You don't mention there's a trick to getting it to spin faster, you have to feel for the motion that is being resisted or it dies, takes a little practice. Making circles, have to start with larger circles, slowly making the circles smaller and smaller to get it to go faster. Surprisingly hard work to get it to go really fast, you'll 'feel the burn' pretty quick. Thanks for the explanation of how they work, never wanted to take mine apart, like it too much, 'fraid i'd break it.
Wow! You described my experience with the original Dynabee to a T. I could never understand why people were so uncoordinated that they couldn't adjust their wrist motion to the rotor. Essentially you were keeping up with the angular velocity. Just like you push a swing at the right time and not randomly.
I wore mine out. There's a teflon (I think) ring that keeps both ends of the axle directly across the center of the housing, and that ring has notches cut in it that the axle fits in. After I had it for about five years, the axle wore through one side of this ring, and that was the end of it. I suppose I could have made a replacement ring for it, but by then I was starting to get tired of it anyway.
i really love just watching this guys explanation on gravity, simple experiments, and he really make some explanation easy.. i really love his channel i still have another one tho but still i love watching it
I paused right at the ad, so I haven't heard your explanation yet (which I am assuming is the correct answer) - I THINK it increases it's speed the same way a swing increases it's speed when you move your legs back and forth... you will intuitively twist your arm at the correct time to speed it up= in the same way you intuitively swing your legs back and forth at the correct time to swing higher... human have that ability because we intuitively understand balance and inertia because we walk on 2 feet and HAVE TO to 'understand'/"feel" it - MIND YOU I have NEVER seen nor PLAYED WITH one of these gyroscopic 'exercise' balls - to me it just seems intuitive as to what is happening and what you feel when you are twisting your arm back and forth...... -- I'll unpause it now and see what you say about it and I'll respond in the reply as to how I did :)
ok, so I described how a human interacts with it and why we are able to get it moving where as Action Lab described the mechanical parts and how it is able to work.... so it's not like he or I were wrong, I was just describing a different part of the explanation...... BUT I NEVER would have guess it was built the way it is... It is INGENIOUS!!!!! I hope you didn't permanently ruin it with that Super Lube!!! LOL I hope you were able to remove it afterwards..... I would REALLY LOVE to have one of these.... where did you get it? I've never seen it before and I think it would be tons of fun as a stress toy/fidget toy :) You did a GREAT JOB of explaining how it works.. much better than I did..... I wouldn't have though it was the friction that made it happen... and I probably wouldn't have believed you until you showed it.... and the way its built so that it only rotates in one direction is AMAZING!!! THANKS FOR THE GREAT VID!! :D
I bought (and was given) a lot of these things in the past. The ones I got were branded "250Hz," since 15,000 rpm was considered the limit. (Not the limit of the Powerball, but the limit of human ability to spin them that fast.) They've since been rebranded 280Hz, due to some people spinning them to over 16,000 rpm, and one guy breaking 17,000 rpm!
Isn't there something about finding the resonate frequency of the motion of your hand to maximize the transfer of energy? Also, isn't this like the interaction of the electric and magnetic fields in AC power? It is the change of position of the momentum vector that causes the gyroscope to process. You can't just move it once, you have to keep moving it to add energy.
The force you exert with your hand does need to be matched to the motion of the gyro wheel inside, but it is sufficiently different from resonance to not categorize it as an instance of resonance. As pointed out in the video, in order to transfer energy you must move in such a way that the ends of the axle are pressed firmly onto the sides of the internal groove. The timing of your motion is crucial. In effect you have to offer a downhill ramp to the gyro wheel. For comparison: imagine holding a plate in your hands, and you are rolling around a marble on that plate. (Let the plate have a sufficiently high rim to ensure that the marble cannot escape the plate.) To get the marble up to speed you wobble the plate in such a way that the marble has a downhill ramp ahead of it all the time. To keep increasing the velocity of the marble you have to increase the frequency of your wobbling motion, to match the speed of the marble. With the powerball: There is transfer of energy when the axle ends are rolling without slipping. The diameter of the axle is a given, so the faster the gyro wheel is spinning the faster the axle is rolling. To keep transferring energy you have to keep matching the rolling speed of the gyro wheel. Incidentally: you can slow the gyro wheel down by shifting the timing. You maintain a motion such that the axle still presses hard against the side of the internal groove, but to slow down the gyro wheel you offer it an *uphill* ramp. About the word 'resonance'. Generally that word is used in circumstances where you have a system that can be whipped to an oscillating state of motion. By matching the frequency of that oscillation you can efficiently transfer energy, increasing the amplitude. Powering the powerball does involve frequency matching, but the motion isn't oscillating motion.
Thanks for finaly confirming my thought about how they work. I always supected that pin in the groove to be driving it, but now I know for sure. Keep up this terrific channel.
I had one of those as a kid my dad got it from a good friend i would always use it in a dark room and it would be so cool to see the room light up brighter and brighter seeing how fast i can spin it.
This video is a gift. I just bought one of those and actually (as a physics total dummy) to understand the whole idea behind it and also tought it was a cool idea to attach magnets on it and do a phone induction charger. This comes right on spot and even though this tool exists since 20 years, only in 2023 we have a video explaining it. It's a work of genius
I've had a Powerball on my desk for years and years now. It's always fun to show to people, and is a great workout for your arm. My version has a little LED readout on the top that shows current RPM and record RPM. It is also battery-less and I assume it works via the same induction(?) method as the lights, as there is a whole load of coiled copper wire in the display. My current record is around 13k, as it gets much harder the higher you go, as you have to fight the increased loss to friction and air resistance etc.
If you turn the axle one way, the other side of the axle would want to move the opposite direction. I don't think it's the friction spinning the axle at all, I think that it's the difference in the angular momentum that you're applying vs the direction that the axle is facing. That classic professor on a spinning chair with a bicycle but in reverse so that he is spinning around and you grab him and stop him (the friction on the axle preventing the ball turning,) the bicycle wheel will then spin a bit.
I also have a toy like that, and I also believe that the reason for the acceleration is related to the forced change of angular momentum, rather than the friction of the axis.
Jiggling it back and forth and causing it to rattle and change direction will wear out the internals faster. The best motion I can describe is face the opening towards the ground and move your hand as if you are swirling a glass of water and trying to swirl the water steadily faster and faster. The people who chase records with these usually keep them spinning in one direction rather than rattling it back and forth :)
If any of you is interested it's Xiaomi Yunmai Wrist Ball in the video... I've bought it myself few days ago and I was really surprised that it's similar quality as 3x expensive NSD powerballs pro.
I've had one of these for probably about 16 years, the original one. It's fairly easy to hit 11,500 RPM, but you don't just wiggle your hand, there is a technique. Imagine stirring a pot of soup with a wooden spoon. That's it Edit: by easy I'm being sarcastic....it's a fire in your forearm, and tricep, but it is doable
I used to use one of these in high school!!! My neurologist had me use it like a fidget, and I also used it to build wrist strength for marching band 🙃
As a physics grad, I just want to commend you on making understanding physics accessible to many people with very little oversimplifying. This is one of your best videos for sure.
I'm really glad the explanation didn't require diving down into Euler angles and all that.
The physics textbooks that I used in college couldn’t explain how to pour piss out of a boot with the directions printed on the sole.
*commend
@@Drad_ They put that
@TheDofflin
Could a Gyro be used to generate electricity? Like, could you use rotation (and the resulting increase in speed) to drive a shaft, kinda like a steam turbine?
Or by using magnets on the rotating part, like an electromagnetic dynamo?
I've wondered about these balls for years (decades maybe?). I always assumed there was something about precession that I didn't understand, which allowed the work to be backfed into increased RPM. Turns out it's actually about the shaft rolling along those races in the ball. Man, this was like pulling a splinter that's been stuck in my brain since I first playd with one of those things. Thank you!
As soon as I got one I couldn't stop thinking about it until I figured it out. I wanted to just believe in the math and say it all worked out somehow, but it feels so much better to actually understand the mechanism!
Anjayyy
Likewise! I got one years ago at a physics teachers’ conference but have really puzzled over the energy transfer
I'm sad it's not through some precession magic
@@TheActionLab ...But do you really understand that friction? Can you build smaller ones, all the way up to bigger ones, and use the motion of robots to harvest the full energy of footfalls, jumps, shock absorbers, etc.? (If you could that would have interesting applications for robots and drones, right?) (And what about a drone that stabs a telescoping ultra-light-weight rod into the ground, then uses gravity plus a bike-chain+friction+"races" to get the gyroscope spinning, along with magnets passing over copper plates+coils to regenerate battery electricity?) The drone could slowly slide down the rod, which would be geared with a small gear running to a much larger gear, so a small downward motion harvests the maximum energy from gravity...like the gravity LED camping lights being used in Africa where no electricity/light exists.
There's no channel that consistently surprises me nearly as much as this does. There's always something new - to me - in every video. Either it's the thing being demonstrated, like this video, or a surprising result of an experiment, or a really intuitive explanation of a phenomenon I'd seen for years. It's the beauty of science - and the world in general - that there's always something to learn, and this is a great place to come for just that.
Yes, I experience the same while watching this channel.
Yes!!
couldn't agree more
You need to explore more. There are a lot more channels that put out consistent quality content.
@@CadillacDriver BOOOO
I remember reading about a practical joke, Perhaps done on "Candid Camera" where they placed a gyroscope on a briefcase with lots of sound insulation and asked people to carry it to another office. The briefcase kept trying to point away from the intended direction and it was a s if a ghost was trying to wrestle it away. The victims tended to become quite alarmed.
That sounds like a cool effect
No being able to explain is one of the main sources of superstition
😂👍 Gaaahahahaa! What a superb idea! Oh geez, you can fit quite a large wheel inside a briefcase! Massive angular momentum possible!
HAHA DO IT!! 😂🎉
I just bought one from Amazon and I can say that whoever came up with the idea of designing a gyroscope which can be used as an exercise/fidget toy is absolutely ingenious.
Big 👍🏻 thumbs up to Physics.
I remember applying WD40 in an attempt to make one of these to go faster. I ended up with a floppy powerball that wouldn't accelerate and it was ruined. This explains it.
Thats a cool point. The friction is actually NECESSARY for accelerating the ball at all.
mmm shoulda used the material F1 wet tires are made of
@@BC-hu6yq Exactly! I foolishly thought less friction would equate to higher rpms. I was sadly mistaken 😂
Specifically the wet tires cause they are formulated to produce more friction at lower temperatures
If it didn't work, then you haven't applied enough WD40.
“Now that we know how that works, we can get even more confused”
I love this way more than I should
Question about why something works if it shouldn't is as much important as question about why something don't work when it should.
The only correction to your description is that both ends of the axle contact opposite surfaces when it is twisted, thus, both contribute to increasing spin. The best motion is that of a wobble plate. You keep the axis ahead of the downward movement which causes it to pivot, the pivot causes it to push up maintaining pressure against the downward movement. The combination of the pivot and upward pressure create enough friction to accelerate the axle and the attached rotor.
It only reverses pivot direction if you get ahead of the axle.
Exactly! This is what people without fine motor skills don't get...
Also you don't get that horrible clicking/banging sound of the axle constantly having to change its friction surface, which can't be good for the overall lifetime of the plastics in particular.
This is the skill of a powerball! Glad other people understand
I had to smile watching this. We've been selling Powerball worldwide since 1998 and have often been asked for the science behind the concept. You nailed it nicely here, thank you. Our customers also often make the mistake of oiling their Powerball in the hope that it'll make the rotor spin faster...a big no-no as you've demonstrated here. All is not lost if you've done so however; TWO deep cleans of all internal components with isopropyl alcohol (while holding the parts with tissue paper to avoid any further contamination with natural hand/finger oil) will do the trick and restore the natural friction once again (two full cleans mind...once isn't enough if you've oiled any part of the internals). Opening the ball can also be done by pressing down on the shell around its circumference while supported by a hard surface such as to flex the two halves which causes them to 'pop' apart instead of using a screwdriver which may damage the plastic.. Hope this helps and thanks again for the content, regards, Rory
I hardly ever comment on your videos, but I wanted say thank you for making them. They have generally been very informative and you make it fun to learn about these topics.
PhD in physics here and was sort of wondering about these toys for years, loved to use them, never quite got curious enough to research it myself (weirdly enough)... That was great. 🙂👍🏼
Really tied some loose ends.
Thx
🙏🏼
As a beginning rock climber and recently just coming across these interesting forearm work tools this video was awesome!!!
Now I can go to the rock climbing gym and when I see them totally understand what’s going on!
Love your content keep it up!
Love these devices. Got my first one back in late 70s. Once you get the feel, you can sense the position of the axis and move accordingly. A bit like surfing a wave.
I got my first powerball (that's what they were called back then) about 15 years ago and i remember getting sore forearms after excessively playing with it the first few days. I also was interested how they work and noticed friction is a big part of it, because I ruined one, by slightly lubricating the running surface of the axle, and on the topic of skill, well i would slightly disagree. I've seen lots of people fail to get it going, because they were not able to feel the movement, once the rotor reaches a certain speed, you can feel the force and basically push it around in a circle slowly increasing the speed. Just wiggling your hand uncontrollably usually ends up stalling the ball.
ha this was my thought... was painful to watch him incorrectly using it
That's what happened to my one - thought I would give it a squirt of wd40 to make it go faster and yep you know what happened!! Great video thank you for sharing.
Did the same thing! 🙈
A common mistake. Many people think WD40 is lube. It is Water Displacement formula 40. Not to suffice as a lubricant!
Guess you learned it a little late😆
What happened
well i think if you would have put it at the right spot it would work. You've got to only put it at these 2 rubber circles or remove them. Then it will go insane i think
10:23
A small error:
The thin metal axis touches at both sides.
But one end touches the upper shell and one end touches the other shell.
So both ends roll clockwise or counterclockwise together.
Nice video! Can you please show us the generator for the LED and the starter mechanism with the spring.
nice that I was looking for this, thx
I just learned precession in physics about one or two months ago and completely failed but this genuinely makes a lot of sense, especially with how you explain it with so little incomprehensible math
I wish you were a school teacher for people everywhere. Always interesting stuff, always explaining things in a way most people can understand. The world could really use more people like you
I've been using those since the 70's, they work well. The first one I had was called a Dyna-Bee. You can hold your arm in different positions to work different muscle groups.
How? The way he was moving the thing in the video just made me think of carpel tunnel syndrome.
Need a Ben WA ball version.
They're this old? I thought it was a late 90s thing. They were called Powerballs at that point, which makes it confusing to google, because of the Powerball lottery.
@@krzysztofczarnecki8238 The selling point for it in the 70's was. The shell was made of the same material as the Astronaut visors because the moon visit was just 6 years prior. I have one from the 90's and a newer one from the 2010's. They do work. Try different arm positions, you'll feel it.
Hats off to you. I’ve been wondering about this for decades. I’m still convinced there’s a way to extract energy from the earth’s rotation using exactly this method.
I got one of these back in 2018. A string pull one. You can start it with a quick flick of a thumb, too, with practice. Was surprised how much of a workout it is for the forearm. Good physiotherapy for people with grip issues :)
Got one back in the 70s. The first ones were amber colored housing.
I had a string one, I used to get mine started by running it across my leg, from thigh to knee.
@@robertmckeown5315 Woah! I didn't know they've been about for that long.
@@robertmckeown5315 Ya, called 'DynaBee', still got mine. Early 70s. 🙂
@@robertmckeown5315 WOAH COOL i didnt know they were around back then!!!! the first powerball i had was amber colored too, what was the inside ball's color?
BOTH ends are touching the groove at the same time, but on OPPOSITE SIDES. If that were not true, there would be a translational force on the rotor. When you reverse the torque on the ball, the rotor ends reverse sides they contact to. There are 4 possible places of frictional contact (2 shaft ends, 2 sides of the groove they can contact). This is in effect a full-wave rectifier, the 4 possible contact points forming a bridge rectifier, continuing to accelerate the rotor despite reversing the ball rotation.
More effective rotor driving occurs if you orbit the ball in a circle (versus simple alternating rotation).
*_FULL BRIDGE RECTIFIER!!_*
I agree about a circle being MUCH more effective.
*your way of explanation simplifies even most complex phenomenons*
You look like a bot
Basically ur saying: The way you explain things also solves other scientific solutions
@@rainhat1 pseud
For those who don't use these a lot, swinging your wrist back and forth isn't the best\easiest way to use these. Everything about the ball is circular. If you swing it back and forth, you'll hurt your wrist. Rotate it like you're drawing circles on paper and you'll avoid joint damage or pain.
Nice video! Never knew that's how they worked and I've been using them for decades.
😂😂😂😂😂😂 you have no idea how funny your comment is.
@@Sam-zu5mr Speaking as another regular Powerball user - trust me, we all know.
When i had my first summer job at a warehouse, i would get on the pallet jack one leg on each side and start turning the handle left and right, and that side to side movement would turn into forward movement, and i could make it go really fast, the whole thing was so intuitive. Dont try this, but in case you have to stop, turn the handle all the way to either side VERY fast and the front wheel would act as the brake.
wow, I had a gyroscopica exercise ball too when I was a child.
I can't believe I'm seeing it again in TH-cam and also found out that it has a way longer history than I thought (from the 70s) 😅
Funnily enough I had one of these and some of my coworkers wasn't able to keep it moving.
Regarding the mechanics I suspected a little bit of how it works but this is great to learn all the small details. Great video as always!
I have a few of them and had the same experience. Various people can not get the smoothness required to get them to a fast enough rpm that they overcome an occasional stumble.
I found if I got it going *really* fast, and handed it to them (easier said than done as that sometimes results in fingers going on the exposed part) they could *keep* it going, and get a feel for the motion, which sometimes resulted in them being able to figure out how to get it going in the first place.
Mine do not have the fancy spring mechanism though, and instead have a cord that you wrap around the ball then use as a ripcord to get them going.
One has lights, one has holes that make it scream like a banshee (oddly i don't use that one hardly at all, even compared to the minimal amount I use the other)
I've been using one of these to exercise forearms, glad to finally understand the physics behind it! Thank you for creating this video as always, amazing stuff!!!!
Thanks!
11:16 the little cheeky "hehe'' gets me xD
I remember having that gyro ball back in 2008, they were called powerballs, my friend had a "speed meter" on it, and we (not me) reached over 20k rpm :)
I have the box for my powerball still sitting on a dusty shelf in my room, no idea where the ball is tho
That's a really nice score. My best was 13,429, I still have a photo I sent in to their leaderboards on this computer. I remember one guy dominated the rankings and could top 20k easily with both hands, at the same time.
I still have mine in the original box with the two start threads since 2005. The battery of the tachometer is dead, but the ball works as new.
I used to play with one of these when I was a little child, but it's so long ago that I had already forgotten.. until I saw it in your video and remembered. Now I want one again!
I just tried mine that i haven't used in years. It starts up with a string wound around the gyro. Put a piece of reflective tape and meassured the RPM to 8000 at the fastest i could get it to spin. I'd get a bit worried if i had a ball spinning at 10k rpm in my hand held together by plastic.
I think the outer housing is a pretty thick chunk of polycarbonate - not much chance of an exploding rotor getting through it.
Bought the first model when they came out called PowerBall, glows blue when its spinning really good, still works flawlessly 20 years later :)
The Chinese inventor who invent this is a genius!
4:26 i almost spit out my beer laughing when he said "the past few years have been really tough on everyone" lol.
I used to have one of those - it had a string start and could get it going mad fast! Don't know how many rpm though but must be thousands probably 4 or 5
PowerBall perhaps? I had a blue and transparent PowerBall, with a tiny screen and a string. Spring loaded makes so much more sense, yet I could get the ball spinning crazy fast with the string and then just go even faster. Yay physics!
@@DipperDK I think that's what my brother had... Blue and yellow.
You could start it by hand if you got the motion right.
I have one with a tachometer. I got it up to 9k and wasn't even the fastest I could get it. Also had one about 15 years ago. We got that one to 11k
@@codylee1682 that's neat! Makes me want to find a new one like that.
@@volvo09 20 bucks on Amazon.
Crazy informative! I instinctively understood it because mine got dirty, and the friction increased to the point where the ball would not move freely anymore to the point that it became unusable. But now that I know you can open them up, I’m going to buy another one and get back to it! Thanks for the video!
I just bought mine 1 week ago.. 5 fase colors model.. very fun... good content
dude this was a great explanation. i got one of these gyros years ago and could never figure out why it increased in acceleration. I remember the instructions explicitly stated not to lube any part of the gyro just keep it clean. Thank you for this great video.
Fun fact: I had one of these, and noticed how gritty the procession axis was, I proceeded to put 3 in 1 oil on the outer ring which rendered the toy useless. These little things are really cool.
I had one of these years ago, I came to the same conclusion and also ruined one of these the same way by lubricating the bearing.
For anyone who wants a gyroscope toy, these are really neat, the feeling of fighting a gyroscope is really strange.
Kudos to the sponsor!! súper important that more people talk about mental health issues without fear or stigma. Thanks!
You are seriously one good teacher 👍
it works because the outter shell allows the gyro to slip in either direction... so .. what pumps the rpms is the constructive interference of your movements... or the inner and outter rotation..ie the movments you make in relation to the spinning gyrocope - you are in control of the outter shell( constructive interefrence is only possible in phi ratios)..once u get it moving fast ( high rpms) grip it with your hand like you want to crush it... you will feel your skeleton vibrate .. and all the muscles up the chain from your hand to your shoulder to your lats turn on.. from here it doesnt take much movement to keep it moving.. more strength to control the tiny movements..... it is used as rehab for gymnast and such... it is tendon/ ligament conditioning
if u get a hold of an older model.. one that has the string start.. instead of the crank spring.. and learn to start it without using the string .. manual ..and then controlled rotation to get it slowly moving ( prettty hard). u will learn more about how it works intuitively...
Gyro, Spin, The Power. Ah, I see where this is going to.
Everything's a JoJo reference 🔥
Yep
if you want to know the speed of rotation, you can match the sound to an app like “sonic” and the sound frequency (lowest harmonic) equals the spinny rate. your ears are good sensors.
There is a device called the sea keeper, same overall gyroscopic idea but to stabilize the boat. I'm very curious what would happen if someone put a sea keeper gyro in an offroad truck. I think it would eliminate nose diving and make out stable in a sharp turn instead of rolling on two wheels.
Interesting idea. If it was powered and gimbaled it might work. Imagine rock crawling Jeeps climbing higher because they have a controllable center of gravity…. with gyros.
Just don’t lose power to your gyros in a high place or you’ll crash.
I know higher tech gyros are powered and encased in a housing under vacuum for high speed rotations… this is where air bearings or actively lubricated bearings help to keep the rotational speed up and the wear down…
Just food for thought..
Well, a sea keeper relies on the following: most boats are much longer than they are wide, so only suppression of rolling is required. The sea keeper gyro uses the stability of the ship against pitching motion as source of leverage to counteract rolling motion. So: if the sea vessel would be some sort of circular raft the sea keeper system would not have the leverage it needs.
On an offroad truck you would need both capabilities: suppression of hard pitching motion and suppression of rolling motion. (But only very rarely both types of suppression at the same time.) That would require a much more complicated system than what suffices for a sea keeper.
If for offroad trucks computerized stabilization is possible at all I expect it would have to consist of an onboard computer taking in video of the ground, processing the input, and with the computer anticipating what is coming up actively moving the suspension to match the profile of the ground as much as possible.
@@cleon_teunissen
Or accelerometers and pitch/roll sensors feeding a programmable/tunable computer that puts out signals to servos on the gimbals and gyro speed control….. less complicated than video to cpu processing with more off the self parts.
Maybe even have the gyro/gimbal assembly on a geared rack on a sliding track to accentuate pitch even more for forward/reverse climbing?
At that point weight and complexity grows.
Rock crawling is usually slow unless it’s King Of The Hammers type racing…
I guess speed of climb and maneuver would dictate type of system.
You idea is better for high speed because the suspension is responding before the obstacle in anticipation rather than reacting.
I guess at what point does the stability system sacrifice durability/serviceability in the middle of nowhere? At what point does it become a robot that a trail rig?
Interesting idea. 🤷🏻♂️
Seeing a video from this channel on these devices makes me happy. One of my high school classmates brought one of those in back in the late 90's before they were available because his uncle invented them and sent him one to test out. It didn't have the spring start, though. It was a pain to get going.
That was fascinating. Had me wondering just how in the world that worked all the way up until almost the end when you explained the friction. I was thinking it was some complex physics to do with it changing directions but being held in one spot or something like that.
Now I want to get one. Not really to exercise with but just to play with haha
I love how you clearly explain the mechanic, instead of trying to stretch it into a 30 minute video
I have the pull string version of this, it’s fun! I got it to at least 8k I think. The noise can get annoying though.
I love this channel. For the science. For the knowledge learned and to watch the evolution of the hair. Best hair on the TH-cam's man.
The device has 3 axis of momentum.
If you add resistance to the second and power to the third, the first one gains incredible momentum.
Fascinating.
I wonder if this applies to rotating magnetic fields too..
Plot twist: You are the gyro and the ball is spinning you and trying to lift you up at the same time.
wow it was very clarifying! Thanks from Brazil😁👍🏼
Are you Leonardo? Of Brazil.
Or are you Leonard ulhoa.
Be yourself kid don't stick to imaginary lines.
@@jagadishgospat2548 ??? I'm Leonardo Ulhoa from Brazil and I really don't understand what your mean...
@@LeonardoUlhoa it is quite alright, I hope you get there one day.
If you «spin» your wrist you get a smooth motion, avoiding that harsh knocking. You can also change which way the ball rotates at full speed by spinning your wrist the other way
I'm going to need Steve Mould to weigh in on this.
For a more comprehensive exercise, try to picture a laser coming out of the center of the ball int he direction away from the palm of your hand, and try to draw circles on the ceiling, floor, or wall with the laser.
He has mastered 「Spin」
YUP!!!
I had a Dyna-Bee blow up when I had it revved up. It made quite a loud noise and blew shrapnel out, but the shell protected my hand. It was really fortunate that a nearby child was not in the blast zone. The rotor material looked like a composite of fine particles like clay that broke into many pieces.
Ouch
If that was one of the plastic-overmolded ones, I think the rotor core was zinc. Obviously a defective rotor in your case, though. There's a thing about zinc, where if it is contaminated with lead, this causes "zinc rot" or "zinc pest", which causes the zinc to crumble. Could be that's what happened to it.
@@BrightBlueJim Interesting about the zinc cores. I am pretty sure it did not have a plastic coating on the rotor. I remember thinking it was way too dangerous the way it was. It mIght have been one the earlier ones.
Great video! Just a little bit of info on the gyro ball, the tiny groove that the axle sits in. As you change the angular momentum by rotating your wrist either clockwise or counter clockwise you can change the direction of the spin. Also, as you rotate your wrist you are causing the axel to run on the top of the groove on one side and the other side of the axle to run on the bottom of the groove. So as you slowly increase wrist rotation the end result is faster gyro rotation! Ps . Where did you get the regular gyro? Again thanks for the great videos!
I was looking for specifically this comment - I felt he missed the point that one axle rides on the top lip and the other on the bottom when you're accelerating. Then the rotation of the spinning gyro can stop when you stop tilting the device. Interestingly, the races can become pitted if you allow this to happen too much at high RPM. A lat point to understand is that the nylon harness ring holds the ends of the axle just so the gyro won't run off in one direction and rub against the inside of the shell when it's spinning in place (ideally only upon startup or at low RPM).
First time I used one of those when I was a kid, I played with it all day & caused my forearms to be so overworked they locked up & I couldn't use my hands the next day.
Fun to play with, just be aware it IS working out your muscles even if it doesn't seem like it.
I have couple of them, the ones called "powerball", with included rpm counter, my record is around 13k rpm. There was a model of powerball that included several magnets on it's rotor, and an attachment meant to generate power to even charge phones!! Really cool gadgets, but just one drop and it's ruined because it gets out of balance, noisy and vibrating machines.
I could only get 10200, congrats.
Great forearm workout.
But sounded like a washing machind in your hands
2:40 similar to what Veritasium shown long before , Lifting spinning 20kg gyro using one hand
5:31 is when sponsor ad ends
I had one back when they were called "Powerballs" and everyone around me had one. Recently I got another one that has the spring so there's no need to use a cord like the old one. The thing is, it's not just twisting your wrist, you need to get a feel and "help" the rotor by syncing to it. If you do it correctly, you'll feel it and it will easily spin faster, otherwise it will start making loud noises as the rotor is fighting against your timing.
😎 i got one of those when they first came out, back in the early 70s, a little primitive compared to this one with the built in starter and the addition of the lights. They originally were called 'DynaBees', 'dynamic' and they sound a little like bees, more a hum really, goes up in pitch with increasing speed. Still have the old one, durable goods. Mine, you have to start by rolling it on a surface or spin it with a thumb. That can be an art in itself, does take a little practice. You don't mention there's a trick to getting it to spin faster, you have to feel for the motion that is being resisted or it dies, takes a little practice. Making circles, have to start with larger circles, slowly making the circles smaller and smaller to get it to go faster. Surprisingly hard work to get it to go really fast, you'll 'feel the burn' pretty quick.
Thanks for the explanation of how they work, never wanted to take mine apart, like it too much, 'fraid i'd break it.
Wow! You described my experience with the original Dynabee to a T. I could never understand why people were so uncoordinated that they couldn't adjust their wrist motion to the rotor. Essentially you were keeping up with the angular velocity. Just like you push a swing at the right time and not randomly.
I wore mine out. There's a teflon (I think) ring that keeps both ends of the axle directly across the center of the housing, and that ring has notches cut in it that the axle fits in. After I had it for about five years, the axle wore through one side of this ring, and that was the end of it. I suppose I could have made a replacement ring for it, but by then I was starting to get tired of it anyway.
"Hey Johny, use the spin!"
In a strange kind of way, you are the reincarnate of Robert Hooke, his doing weekly demonstrations of science for the early Royal Society.
I've been waiting for this for many years! Ever since I was a kid and used that thing to train for Badminton!
Thx
i really love just watching this guys explanation on gravity, simple experiments, and he really make some explanation easy.. i really love his channel i still have another one tho but still i love watching it
Now I am extremely curious about where this hand exercise come to play 😲
I paused right at the ad, so I haven't heard your explanation yet (which I am assuming is the correct answer) - I THINK it increases it's speed the same way a swing increases it's speed when you move your legs back and forth... you will intuitively twist your arm at the correct time to speed it up= in the same way you intuitively swing your legs back and forth at the correct time to swing higher... human have that ability because we intuitively understand balance and inertia because we walk on 2 feet and HAVE TO to 'understand'/"feel" it - MIND YOU I have NEVER seen nor PLAYED WITH one of these gyroscopic 'exercise' balls - to me it just seems intuitive as to what is happening and what you feel when you are twisting your arm back and forth......
-- I'll unpause it now and see what you say about it and I'll respond in the reply as to how I did :)
ok, so I described how a human interacts with it and why we are able to get it moving where as Action Lab described the mechanical parts and how it is able to work.... so it's not like he or I were wrong, I was just describing a different part of the explanation...... BUT I NEVER would have guess it was built the way it is... It is INGENIOUS!!!!!
I hope you didn't permanently ruin it with that Super Lube!!! LOL I hope you were able to remove it afterwards..... I would REALLY LOVE to have one of these.... where did you get it? I've never seen it before and I think it would be tons of fun as a stress toy/fidget toy :)
You did a GREAT JOB of explaining how it works.. much better than I did..... I wouldn't have though it was the friction that made it happen... and I probably wouldn't have believed you until you showed it.... and the way its built so that it only rotates in one direction is AMAZING!!!
THANKS FOR THE GREAT VID!! :D
Arigato, Gyro.
Jojo reference
I bought (and was given) a lot of these things in the past. The ones I got were branded "250Hz," since 15,000 rpm was considered the limit. (Not the limit of the Powerball, but the limit of human ability to spin them that fast.) They've since been rebranded 280Hz, due to some people spinning them to over 16,000 rpm, and one guy breaking 17,000 rpm!
Isn't there something about finding the resonate frequency of the motion of your hand to maximize the transfer of energy?
Also, isn't this like the interaction of the electric and magnetic fields in AC power? It is the change of position of the momentum vector that causes the gyroscope to process. You can't just move it once, you have to keep moving it to add energy.
The force you exert with your hand does need to be matched to the motion of the gyro wheel inside, but it is sufficiently different from resonance to not categorize it as an instance of resonance. As pointed out in the video, in order to transfer energy you must move in such a way that the ends of the axle are pressed firmly onto the sides of the internal groove.
The timing of your motion is crucial. In effect you have to offer a downhill ramp to the gyro wheel. For comparison: imagine holding a plate in your hands, and you are rolling around a marble on that plate. (Let the plate have a sufficiently high rim to ensure that the marble cannot escape the plate.) To get the marble up to speed you wobble the plate in such a way that the marble has a downhill ramp ahead of it all the time. To keep increasing the velocity of the marble you have to increase the frequency of your wobbling motion, to match the speed of the marble.
With the powerball:
There is transfer of energy when the axle ends are rolling without slipping. The diameter of the axle is a given, so the faster the gyro wheel is spinning the faster the axle is rolling. To keep transferring energy you have to keep matching the rolling speed of the gyro wheel.
Incidentally: you can slow the gyro wheel down by shifting the timing. You maintain a motion such that the axle still presses hard against the side of the internal groove, but to slow down the gyro wheel you offer it an *uphill* ramp.
About the word 'resonance'. Generally that word is used in circumstances where you have a system that can be whipped to an oscillating state of motion. By matching the frequency of that oscillation you can efficiently transfer energy, increasing the amplitude. Powering the powerball does involve frequency matching, but the motion isn't oscillating motion.
Thanks for finaly confirming my thought about how they work. I always supected that pin in the groove to be driving it, but now I know for sure. Keep up this terrific channel.
Sir big fan wanted to have a teacher like you , imagining a time I would be able to see you offline
Lol at that chuckle in the background right after he said on 11:14 "Now you do get better at it the more you play with it"
Yeah... A GYROscope
Lmao
Hi Giorno!
I had one of those as a kid my dad got it from a good friend i would always use it in a dark room and it would be so cool to see the room light up brighter and brighter seeing how fast i can spin it.
This video is a gift. I just bought one of those and actually (as a physics total dummy) to understand the whole idea behind it and also tought it was a cool idea to attach magnets on it and do a phone induction charger. This comes right on spot and even though this tool exists since 20 years, only in 2023 we have a video explaining it.
It's a work of genius
Gyro Zeppeli approves
Yes
I have lived my entire life to use that excercise toy
I will learn JJBA SBR
Hold on, lemme get Slow Dancer...
You are a master presenter and a dedicated physics research advocate. Excellent video again!
never clicked so fast in my life
Wot, did it excite you so much!
Ok.
I've had a Powerball on my desk for years and years now. It's always fun to show to people, and is a great workout for your arm. My version has a little LED readout on the top that shows current RPM and record RPM. It is also battery-less and I assume it works via the same induction(?) method as the lights, as there is a whole load of coiled copper wire in the display. My current record is around 13k, as it gets much harder the higher you go, as you have to fight the increased loss to friction and air resistance etc.
I was lucky to buy one of the last diablo Powerball, personal record 15000
I wonder if it uses the voltage in the coil to determine approximate RPM...
Ever see what happens to a spinning T shape in space? It periodically inverts its orientation while maintaining its rotational velocity.
If you turn the axle one way, the other side of the axle would want to move the opposite direction. I don't think it's the friction spinning the axle at all, I think that it's the difference in the angular momentum that you're applying vs the direction that the axle is facing. That classic professor on a spinning chair with a bicycle but in reverse so that he is spinning around and you grab him and stop him (the friction on the axle preventing the ball turning,) the bicycle wheel will then spin a bit.
I also have a toy like that, and I also believe that the reason for the acceleration is related to the forced change of angular momentum, rather than the friction of the axis.
This is a jojo part 7 reference
Jiggling it back and forth and causing it to rattle and change direction will wear out the internals faster. The best motion I can describe is face the opening towards the ground and move your hand as if you are swirling a glass of water and trying to swirl the water steadily faster and faster. The people who chase records with these usually keep them spinning in one direction rather than rattling it back and forth :)
Zeppeli would be proud
If any of you is interested it's Xiaomi Yunmai Wrist Ball in the video... I've bought it myself few days ago and I was really surprised that it's similar quality as 3x expensive NSD powerballs pro.
Gyro's Ball Breaker? 🤨
NYO-HO!
The post edit chuckle at 11:16 (watch from 11:13 to get it) is exactly what I needed today.
I've had one of these for probably about 16 years, the original one. It's fairly easy to hit 11,500 RPM, but you don't just wiggle your hand, there is a technique. Imagine stirring a pot of soup with a wooden spoon. That's it
Edit: by easy I'm being sarcastic....it's a fire in your forearm, and tricep, but it is doable
I used to use one of these in high school!!! My neurologist had me use it like a fidget, and I also used it to build wrist strength for marching band 🙃
Drums?
Gyro's successor