Leverage

Leverage is the mechanical advantage or power gained from the use of a lever. 

Lever
A lever is a simple machine consisting of a beam or rigid rod that hinges on a pivot point called a fulcrum. Levers are commonly known as a means of lifting heavy objects with minimal effort. More specifically, levers can provide a mechanical advantage (leverage), which is the measure of the force amplification achieved by use of a tool.

There are four parts to a lever: lever arm, fulcrum/pivot, effort (input force) and load (output force).

The advantage gained from the use of a lever depends on how far away the effort and load is from the fulcrum. To create the maximum mechanical advantage, you want the effort as far away as possible from the fulcrum and you want the fulcrum as close as possible to the load. 

More specifically, if the distance from the fulcrum to where the input force (effort) is applied is greater than the distance from the fulcrum to where the output force (load) is applied, then the lever amplifies the input force. If the distance from the fulcrum to the input force is less than from the fulcrum to the output force, then the lever reduces the input force

There are three classes of levers:

1. First Class Lever
With first class levers, the fulcrum lies between the effort and the load.

2. Second Class Lever (wheel bar
With the second class lever, the load is between the pivot and the effort.

3. Third Class Lever
Finally, with third class levers, the effort is between the fulcrum and the load.

A simple way to remember the three types of levers is the mnemonic FLE 123. The F refers to fulcrum in the middle which is a 1st class lever. L is for load in the middle, a 2nd class lever. E is for effort in the middle, which is a 3rd class lever.

Mechanical Advantage & Disadvantage

Points to remember:

1) An effective lever is rigid. A lever arm which is flexible can lead to inefficiencies. 

2) An effective fulcrum is solid. The fulcrum must be capable of handling the load without breaking. 


Principles and Concepts for Martial Arts

Rube Goldberg: Levers

Teach Engineering: Levers That Lift

Danaher outlines 4 Mechanical Principles You Need To Understand To Vastly Improve Your BJJ

John Danaher Says This Is One of the Most Overlooked Parts of a Successful Submision

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http://judotalk.com/profiles/blogs/judo-physics-ranking-martial-arts-throws

https://fs.blog/category/mental-models/

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https://www.youtube.com/watch?v=K6RYpUjfMOI