Quite impressive that these speeds were reached so quickly compared to with the motors. Btw, maybe you could try using a steel lego axle instead of the plastic ones to mitigate the problem of the axle bending. I wonder what speeds could be achieved with that
There's just something about this channel thats so satisfying and deserving of the views. Maybe it's the fact there's no bs, no merch plugs, and that it gets right to the point. Eitherway, love the random experiments, keep it up!
That tire could blow a 12 foot hole in the wall had it broke off the axle. I mean the damage it could create. My friend did this once and the tire came loose at 6000 rpm and it blew out his Wi-Fi. They had to use cellular data for 8 hours!
Man I love this. My kid is still 3 years old and we just introduced Lego as next step from Duplo. I can't wait to do stuff like this and teach physics :)
For me, it was from Mega Bloks to LEGO and Mega Bloks, (I think it was them) because they were somewhat compatible. Probably didn't have motors or technic stuff, though.
The wheel looks around 7 cm in diameter, meaning if this tiny wheel was on the ground, spinning at 20.000 rpm, it would be traveling at a speed of ~ 264 km/h For reference a regular car tire on the freeway does around ~720 rpm to travel 115 km/h If your car tires were doing 20.000 rpm, you would be traveling at 3.150 km/h, or about 20% faster than an AK47 bullet
What if there was somehow a method to release that wheel like a beyblade? It would become a weapon of mass destruction OR a really really good beyblade
I see someone else has already suggested the steel axle. The ripcord was a great idea! I wonder if the rubber tire induces air resistance. Maybe you can achieve a higher top speed by removing the rubber tire
@Marshall Williams I'd be interested to see the tradeoff if the rubber tire was instead a lead wheel: You'd get an increase in duration of the system, but probably at the cost of RPM given how briefly the energy inputted lasts.
Do you think intentionally setting the lowest gearing to disconnect after dumping the power in would make it work better? The last one at least seemed to spin longer when that happened unintentionally. Not sure how you would make it disengage, but I wonder how long it could go, and what might make the length of time spinning go up.
youte definitly right, if they disconnected the gearing from the wheel at the end of the pull, that would allow it to spin longer and free-er. Idk that it would improve rpm, but it would give more time to measure the rpm before it dropped off.
@@EllaBananas you're absolutely right it wouldn't spin faster; it only speeds up because of power being put into it, and disconnected it can't put in more power. But spin time and reducing friction tests would be neat to see.
@@Airin258 good point, I forgot that was the only one lubricated, but removing the second shaft by disconnecting it making it spin longer could be interesting. Also, decoupling might make it spin more as less sections experiencing friction, but also less inertia because it is removing weight, but also also it's a minor weight change because the spinning wheels are obviously vastly heavier, but also also also the bearings on the spinning section could be made more focused on low friction while the power train focuses on maximum power and ignores friction because the decoupling . . . basically it could be cool to try?
The speed doesn't really matter that much since it's all about energy in vs energy out. We would be talking about some fraction of how much energy our hands provide into the system which isn't that much. Imagine people using exercise bikes to provide electricity, it hasn't caught on because it's not that effective.
Yes, obviously. The less mass on the wheel, the less torque needed to spin it, even with the part limitations (as in, the axle twist and the damage from lack of lubrication). So given the same amount of torque applied (same person and gear set), you will see an increase in RPM.
What I like with your channel, to compare with other "bricks experiment channel" is that you do not want to break record, just to break record, which can lead to bad design choice. You make it for testing, with the correct solutions. Even if I am not interested by breaking record, I am always surprised by the idea you come up to figure out the problem in a smart way, instead of just using 100x motors for instance. It is a nice way to show how a problem can be solve using mechanic.
That's cool! And while it's fun to experiment with LEGO it actually had been interesting to see what's achieveable with metal instead of plastic. It should allow far higher rpm.
If you're attempting the highest RPM I'd suggest using a flywheel with a smaller diameter than the wheel and tyre. The larger the diameter the faster the surface speed, if you like, of the outer diameter of the flywheel, thus resulting in a higher energy requirement. You probably wont see much improvement without using the ripcord method however. All in all, though, a very enjoyable video 👍
its so cool how you can multiply the speed by getting a bigger wheel to rotate a smaller one, the amount of energy this would be making would be quite impressive
For the string and lube tremendously gives me beyblade vibes, for the ones who doesn’t know (the string and lube) actually works like a string launcher in beyblade, sheesh I wish I could see a beyblade launch with the use of lego. Your videos are amazing!
I'd be interested in seeing how fast you can get the wheel to spin by hand, but continuously, maybe for about 30 seconds or so. Getting a high peak RPM is interesting, but using a rip cord design makes it impossible to maintain that speed once the string is exhausted.
This is a neat twist to the spin a wheel challenge! Really brought joy to my night Would there be a way to reinforce the input shaft? Perhaps could make hand turning get a little further
That was really, really cool. It makes me think about how human tech is so advanced that a toy can be made to spin a thing faster than was probably even possible with state of the art tech what, 300 years ago?
So I was curious how fast a vehicle with these tires would be travelling if we used the final figure of 19,300RPM: Lego studs are spaced 8mm apart from stud centre to stud centre. The wheel used appears to be about 8 studs long ending in the centre on either side. This means that our wheel has an approximate diameter of 7 times the stud centre spacing ([Stud 1 to Stud 2] + [Stud 2 to Stud 3] + ... + [Stud 7 to Stud 8]) which is 56mm or 5.6 cm. The circumference of a circle is 2*π*r, or π*d, giving us a circumference of π*(56mm) or 175.9291886...mm, rounded to 175.929189mm since we are multiplying by 19,300 RPM, and we want to be as accurate as possible here. multiplying our circumference by our RPM will give the theoretical speed of this wheel. 175.9291886mm*19,300RPM gives us 3,395,433.33998mm per minute (RPM = Rotations Per Minute). We then multiply by 60 to get the distance travelled in an hour, which is 3,395,433.33998mm*60 = 203,726,000.3988mm/hour. Finally we convert this to KM which means we divide our result by 1,000,000, giving us a speed of 203,726,000.3988mm/hour÷1,000,000 = 203.7260003988km/hr, rounded to 203.7km/hour. This of course ignores factors like the wind resistance on the theoretical vehicle, friction between the tire and road, and the weight of said vehicle, but this was still a fun thought experiment.
I think you could hit 20k rpm if you made the construction more sturdy, I've noticed that with a couple of your builds, that things are vibrating quite a lot.
I feel like you could potentially hit the speed of sound at the edge of a large wheel. At 20k rpm you'd need about a 33cm diameter wheel. Not sure how feasible it would be to make the whole thing out of lego, tho.
Maybe steel axels, gears and supports but then I suppose eit kinda defeats the purpose of being made relatively easily using lego. Still would be cool too see
Nah, it already is way beyond speed of sound. Sound is moving by 340m/s, so 34.000cm divided by 20.000 RPM = 1,7cm circumference per rotation would already be enough. 1,7cm divided by π = 0,54cm diameter of the wheel
@@philruu you're confusing rpm with Hz. 20k rpm is 333.3Hz At 333.3Hz you need a perimeter of 340/333.3=1.02m to reach the speed of sound This gets us a radius of 1.02/(2pi)=0.162m, which is a diameter of 32cm.
