Cable and Pulley Routing help needed for Fitness Machine

AI Thread Summary
Edmond is seeking expert assistance for designing a fitness machine that utilizes up to fifteen pulleys, specifically to achieve a mechanical advantage where one area requires half the travel distance of another. He aims for a setup where 1/2 pound at one point equals 1 pound at another, indicating a need for precise cable and pulley arrangement. The discussion highlights the importance of understanding the mechanical interactions between the pulleys and weight stack. There is a request for clarity on whether the cables are directly attached to the weight stack or routed through a pulley system, as this will affect the design outcome. Expert guidance is sought to resolve these mechanical challenges effectively.
Edmond Daunte
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Hello,

I am trying to put together a fitness machine that used up to fifteen pulleys. Is there anybody here that is an expert in this field or knows someone who is? I am willing to pay a reasonable consulting fee if they can help solve my problem.

Thank you,

Edmond
 
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What kind of expert are you looking for?

If this is checking the theory behind the cable and pulleys, it should possible to help.

Cheers
 
Well I am ok with the concepts but not good at the exact cause and effect of cable and pulley mechanical advantage. I have a problem where one area of this fitness device needs half the travel of another area. Ideally the area with the desired half travel would have a mechanical advantage so that its for example 1/2 pound would be equal in resistance to 1 pound at the end of the front cable where the weight plates are.

So "B" needs to go half the distance as "A"

1/2 a pound at X needs to equal 1 pound at Y

The pulleys you see can be arranged in any way or more pulleys/cables added. Please help!

Thanks!
 

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Hi there,

From your diagram, I can't see if the cables in A are attached directly to the weight stack, or if you want to hook them to a pulley. The result will be different in the two cases scenarios.
 
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