Simple Pulley analysis

reymart.laranjo
Enthusiast

Simple Pulley analysis

reymart.laranjo
Enthusiast
Enthusiast

Hi,

Is there a way to simulate a pulley like this.

reymartlaranjo_0-1694669937506.png

Green ones are the constraints. Rope behavior. and a simple pulley that pulls the ropes/cables.

I wanted to get the reactions to the constraints.

kind regards,

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John_Holtz
Autodesk Support
Autodesk Support

Hi @reymart.laranjo 

 

I cannot think of a way to simulate a pulley where one rope can get long and the other rope gets shorter (based on how the pulley rotates). But if you can ignore that effect, your figure is just a four bar linkage:

  • The ropes would be rod elements: "Connectors > Rod". See this article for creating truss-like structures. Solved: Truss in ASM - how in Nastran in CAD - Autodesk Community - Inventor Nastran
  • The pulley would be a beam element that is created in an Inventor sketch. You should create 2  line segments: one from the center to the where the left rope is tangent to the pulley, the other segment from the center to where the right rope is tangent. This will give a point at the center of the pulley where you can apply the load (and other things).

Note that 4 bar linkages are statically unstable. You will need to do something to get the analysis to solve, such as a dynamic analysis (nonlinear transient response) or springs or constraints to make a static analysis stable.

 

John



John Holtz, P.E.

Global Product Support
Autodesk, Inc.


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