There's a similar neat video, "Most People Don't Know How Bikes Work", where they fix the steering so the handlebars can only be turned left, and people then aren't able to turn left.
Holy moly!! I didn't realize I didn't know how I actually ride a bicycle!!
Obligatory sound track for this excellent post:
> When the distance between the force-line and the center of mass is large, the box spins faster as well. That distance doesn’t change the acceleration of the box to the right and both boxes move with the same linear speed. However, that distance affects the angular acceleration of a box – the longer that arm, the faster the box spins.
This does not make sense to me. If the two forces are truly of equal magnitude, then shouldn't the one that is in-line with the center of mass accelerate it faster, since 100% of the force is being converted to linear momentum, while the off-center force is being split between increasing linear momentum and rotational momentum?
This would appear to violate the conservation of energy.
It's pretty much impossible to believe without thinking it through, and yet everyone naturally intuits it.
It's one of my favourite examples of how the brain can just 'feel' forces and make the right adjustments incredibly fast. So amazing.
I wish physics teachers start using geometric product of vectors, instead of the cross product. This allows forces and torques to be combined into a single concept "Forque". Really, translations are just rotations around infinity and rotations are just composition of two reflections. If we allow the algebra to take care of rotations, physics becomes a lot simpler.
Compare bicycles with steel making, for example. Steel making happened thousands of years ago. The modern bicycle was what - under 200 years ago?
Bikes seem like such a primitive technology, and yet as this article demonstrates, it takes a lot of engineering to design even primitive products.
It makes me wonder how many other simple or primitive products are out there which have yet to be discovered.
Be careful if you have deadlines for today though, you may be there for a long and awesome time.
How many neurons does it take to ride a bycicle?
How I wish our schools would teach like this.
Voluntary contribution of $3 or more per article, via Patreon: https://www.patreon.com/ciechanowski
(Not sure what "per article" means though. How to donate for past articles? Will I get billed whenever a new article drops?)
Not fancy looking, but very interesting.
If the applied force is anchored to the ground too, if doesn't matter how heavy the planet is.
Derek Muller (Veritasium) on YouTube has a related video diving into the mechanics of bicycle riding. It shows what happens if you prevent the rider from performing the countersteer before leaning into a turn [1].
Except you don't really turn the handlebars to steer, movement is far more than just pedaling and it's never an effortless activity if done right. Everything else in this sentence is correct though ;)
"Computers are like a bicycle for our minds." https://youtu.be/ob_GX50Za6c
E=(mv^2)/2 - so we put more energy accelerating the bike from 10-20m/s than 0-10m/s, no?
Yet a=F/m - which suggests the acceleration is proportional to force, which would suggest that applying force F for time t should speed you up 0-10m/s the same way as 10-20m/s?
I suspect the force applied to the pedals is not the force which is acting on the bike (counter-force of the ground-bike system) and this second force is somehow relatable to the current speed of the bike, no?
I've been having some trouble adjusting the tension in my spokes lately. It seems like no matter how much I try, I just can't seem to get it right. Does anyone have any tips or tricks they could share with me?
On a related note, I've been wondering about the differences between mountain bikes and road bikes. One thing I've noticed is that when you take a sharp turn on a mountain bike, you tend to move the bike away from your body. But on a road bike, you maintain that alignment with your body and the frame. It's fascinating how these small differences can have such a big impact on the way we ride.
What do you all think? Have you noticed any other differences between these two types of bikes? Let's chat and share our experiences!
https://www.gianlucagimini.it/portfolio-item/velocipedia/
> Little I knew this is actually a test that psychologists use to demonstrate how our brain sometimes tricks us into thinking we know something even though we don’t.
> I collected hundreds of drawings, building up a collection that I think is very precious. There is an incredible diversity of new typologies emerging from these crowd-sourced and technically error-driven drawings. A single designer could not invent so many new bike designs in 100 lifetimes and this is why I look at this collection in such awe.
In reality, the wheel turns slightly away from the turn. This is called "counter steering"
This is a great article. It showcases lots of the "simple, but surprisingly advanced" things surrounding bicycles. Which was what got me hooked in the first place. The visualization of how you have to turn right to go left is excellent. I've mentioned that fact multiple times here on HN, it's not commonly known, you just "do it" when you bike! And it explains why you sometimes can feel the curb "sucking" you towards it when you try to avoid it: you unconsciously avoid turning the wheel towards it, but that actually makes it so that you're unable to actually steer away from it!
Humans burn something like 750Kc per hour on a bike, and go 15 miles
A Wh is ~1Kc (0.8:1 but ok)
That makes bikes, what, 5X more efficient?
I'm not even sure if the force responsible for this is friction-related, or torque related, or some combination of both (probably the latter). The force is transmitted to the chaindrive in an off-axis manner, but the pedal itself is further removed from the axis, so when you push down on the pedal axis that's ahead of the bottom bracket axis - one side will tighten clockwise from the pedal's perspective, and the other side will tighten anti-clockwise.
Wow I got it right after going through this post! That's a first, though I'm still not sure I got all the forces right.
> You may wonder how the wall knows how much back-force to apply, so let’s look at the interaction between these two objects up close and in slow motion. As we apply the force, the box actually starts accelerating into to the wall, pushing its surface to the right:
> As the box moves to the right, it compresses the molecules in the wall, which create a spring-like force that pushes the box back. If that force is too small to balance the pushing force, the box will continue to move to the right, which compresses the wall even more, creating an even larger push-back force.
As a fellow cyclist I've always thought about the physics on rides, it's why changing up the gear and getting the difference feels so good, but I don't think I could ever go into this kind of detail.
Beautiful creative work. Amazing effort. Top
I'm not sure about this. Yes, static weight _is_ fixed, but a rider can vary their dynamic downforce considerably. Skilled off-road riders (i.e. mountain bikers) vary their dynamic downforce for various reasons, including traction.
As always, I'm up for a discussion on this; it is possible the conventional mountain bike wisdom is a butchered version of the physics.
P.S. For offroad riders (i.e. mountain biking): some things to look up if you don't know them: the "attack" position; the "cockpit"; pumping; row and anti-row motions.
is it proven at least that "the bike needs to turn into the fall (the handlebars moving not necessarily being the cause of the bicycle turning)"?
I really wanted the article to close its opening statement that "There is something delightful about riding a bicycle", by closing with the initial simulation, but with the rider embedded in an infinite procedurally generated landscape of rolling green hills and small villages.
If we generalize this, we are missing out on some skills, which are awkward but which our bodies and nervous system can learn? but perhaps we are not trying to learn thinking its risky?
But as I've become older I'm less interested in it and more willing to accept things "just work". I'm pretty sure that no part of the bicycle was invented by thinking about it this way. This is kind of a reverse engineering exercise. The inventors of the bicycle just knew that if you sat on a moving wheel somehow you could balance. They knew that if you put something soft around the wheel it would feel smoother etc. Nobody was sitting there thinking about crates moving and suddenly thought, what if it was two wheels with a person on it?
I don't know. Maybe it's because I already knew all of this stuff too (I'm an avid cyclist who has studied Newtonian physics). But I found this one a bit exhausting.
In the book Snow Crash by Neal Stephenson, there is a quote that goes something like this:
"Most cars have tires that only contact the road in an area about the size of your tongue. Hiro's car had big radial tires where the contact area was the size of a fat person's thigh."
Seriously though, wonderful work.
Now do running?!
https://fellrnr.com/wiki/Running_Form#Running_Movements
I'd love to be able to see a runner in motion like the bicycle and then use sliders to adjust legs and arm movements with physics applied correctly.
If you apply the same force over the same amount of time to both boxes, the same amount of energy goes into both boxes. As one box is rotating faster, it has a higher rotational energy than the other box. As both systems (boxes) got identical amounts of energy this means, that the slower rotating box should move faster to the right because more energy goes into this movement. Becaus E_input has always to be the sum of E_forward and E_rotation. Am I wrong and why?
I asked it (with no context), 'What is "Bicycle (ciechanow.ski)" referring to?':
Response: "Bicycle (ciechanow.ski)" is referring to a blog post by Bartosz Ciechanowski, a software engineer and blogger. In this particular post, titled "Bicycle", he provides an interactive, in-depth explanation and visualization of the physics and mechanics behind the bicycle, covering topics such as steering, gyroscopic effects, trail, and more. The post aims to provide a comprehensive understanding of why bicycles are stable and how they function.
In a different response it volunteered the correct URL.
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