Control theory | Rotation

Falling cat problem

The falling cat problem is a problem that consists of explaining the underlying physics behind the observation of the cat righting reflex. Although amusing and trivial to pose, the solution of the problem is not as straightforward as its statement would suggest. The apparent contradiction with the law of conservation of angular momentum is resolved because the cat is not a rigid body, but instead is permitted to change its shape during the fall owing to the cat's flexible backbone and non-functional collar-bone. The behavior of the cat is thus typical of the mechanics of deformable bodies. Several explanations have been proposed for this phenomenon since the late 19th century: * Cats rely on conservation of angular momentum. * The rotation angle of the front body is larger than that of the rear body. * The dynamics of the falling cat have been explained using the Udwadia–Kalaba equation. (Wikipedia).

Falling cat problem
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Falling cat

Cat falling and landing on 4 feet... Incredible! Credits: Microsoft Encarta

From playlist Mechanics, Elasticity, Fluids, Diffusion

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Donut escapes cat

Donuts are paralyzed with embarrassment (and as a result unable to escape) when someone is laughing at them.

From playlist Videos with my cats!

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SPIDER CAT

The surface the cat is climbing is a window screen, and it’s made on METAL WIRE! (Not good for getting claws out of)

From playlist Videos with my cats!

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Noisy ca launches escape mission and fails

Other cat makes an appearance too

From playlist Videos with my cats!

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Falling Cat - Rotation with zero net angular momentum

See: http://en.wikipedia.org/wiki/Falling_cat_problem This explains how cats turn around while having zero net angular momentum during a fall. Cat falling seen from a good angle to see the rotation: http://www.youtube.com/watch?v=Ua4Gh_4XdwQ Cat falling from around the minimal height to

From playlist Angular Momentum

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What is common between falling cats and the Quantum Hall Effect? by Alexander Abanov

PUBLIC LECTURE WHAT IS COMMON BETWEEN FALLING CATS AND THE QUANTUM HALL EFFECT? SPEAKER: Alexander Abanov (Stony Brook University, New York) DATE: 10 August 2018, 16:00 to 18:00 VENUE: Chandrasekhar Auditorium, ICTS, Bangalore. Have you ever seen how a cat lands on its feet? Even 6 we

From playlist Public Lectures

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How does a slinky fall!

Well, without taking into account air drag, if you consider half the mass of the slinky to be concentrated on the top part and another half on the bottom part, you can see that the top mass is influenced by two parallel forces (gravity and elastic force downwards) and the bottom mass is in

From playlist MECHANICS

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add 'em cats; there are two!

it's 3D with a twist. the rest of the room is coherently 3D, but the cat is different in each eye! be the best multitasker you can be by delegating one cat to each eye! lol, it's higher than 1080p music by http://youtube.com/losmmorpg Not using YouTube's 3D function because I got the di

From playlist Videos with my cats!

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Falling cat demonstrations go sour by Andy Ruina

COLLOQUIUM : FALLING CAT DEMONSTRATIONS GO SOUR SPEAKER: Andy Ruina (Cornell University, US) DATE: Mon, 25 April 2022, 15:30 to 17:00 VENUE: Online and Ramanujan Lecture Hall ABSTRACT There are two classes of interesting, at least to me, physical behavior that follow from the impossibi

From playlist ICTS Colloquia

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Double Jumps - Invent with Scratch 2.0 Screencast

Free online course in Scratch: https://www.udemy.com/scratch-game-programming/?couponCode=GET_SCRATCHING Many more games in the free Scratch Programming Playground book! https://inventwithscratch.com/book Run this game program in your browser at http://scratch.mit.edu/projects/11708677/

From playlist Scratch Programming

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Highlight: Pitfall style game 24 - More falling into pits

Brooks is building a Pitfall clone called Jungle (until he finds a better name). Don't know what pitfall is? Watch this gameplay of the original game at https://www.youtube.com/watch?v=pslbO6Fddhw&t=391s. On this stream Brooks Finished allowing the player to fall into the pit. It doesn't

From playlist Pitfall clone in web assembly (Rust)

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Q&A - Great Moments in Science - with Dr Karl

Dr Karl Kruszelnicki answers questions from the audience after his talk, including a special animated explanation of why it's safer for a cat to fall from 32 floors up than 7. Watch Dr Karl's talk here: https://youtu.be/XXaXXak5SG0 Subscribe for regular science videos: http://bit.ly/RiSubs

From playlist Ri Talks

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AI 101 with Brandon Leshchinskiy

MIT RES.6-013 Neuroscience and Behavior, Fall 2021 Instructor: Brandon Leshchinskiy View the complete course: http://ocw.mit.edu/courses/res-6-013-ai-101-fall-2021/ This is a video of Brandon Leshchinskiy's presentation "AI 101," which provides an introductory overview of the application

From playlist AI 101 with Brandon Leshchinskiy

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Week 0: Friday - CS50 2007 - Harvard University

Introduction. Bits. Binary. ASCII. Programming. Algorithms. Scratch. Statements. Boolean expressions. Conditions. Loops. Variables. Threads. Events. C.

From playlist CS50 Lectures 2007

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Why pedestrian bridges wobble: synchronisation and the wisdom of the crowd

Oxford Mathematics Public Lecture: Alan Champneys - Why pedestrian bridges wobble: synchronisation and the wisdom of the crowd. In this lecture Alan Champneys argues that Mathematics is at its best when it challenges assumptions. For example the wobbling of the Millennium Bridge in London

From playlist Oxford Mathematics Public Lectures

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Programming - CS50's Understanding Technology 2017

00:00:00 - Oscartime 00:01:09 - Software 00:01:44 - Finding Mike Smith 00:06:01 - Phone Book Algorithm 00:07:40 - Pseudocode 00:10:45 - Programming Constructs 00:11:35 - C 00:16:00 - C++ 00:17:26 - Python 00:20:38 - Other Programming Languages 00:21:24 - Introducing Scratch 00:26:03 - hell

From playlist CS50's Understanding Technology 2017

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Black hole Firewalls - with Sean Carroll and Jennifer Ouellette

What would you experience if you jumped into a black hole? Click here to subscribe for more science videos: http://bit.ly/RiSubscRibe Conventionally, physicists have assumed that if the black hole is large enough, the gravitational forces won't become extreme until you approach the singul

From playlist Ri Talks

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suite life on deck - CAT EDITION

The cat, named “Good”, is now on the deck, meowing super loudly!!!

From playlist Videos with my cats!

Related pages

Motion planning | Connection (principal bundle) | Nonholonomic system | Control theory | Rigid body | Angular momentum | Parallel parking problem