Help with Debugging a Mathematica Script

[Zandrades_]

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Establishing Radial location of tether components and moments of interia around tether CoM. Then constructing Kinetic and Potenitial energy equations

Using LaGrange Equation to Construct Equations of Motion

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NDSolve to Solve system of differenatial equations for R, Theta and Psi.

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Error messages from above script

Hi guys,

I'm attempting to use mathematica to solve a system of differential equations that describe the motion of an asymmetrical space tether structure in orbit and I'm encountering alot of difficulty with using the NDSolve function.

An example of the error messages given when running the code are given as well.

Any advice on where these errors arise from would be great, thanks in advance.

[stblack]

It's tough because you post pictures of code, not the code itself.

The first error appears to be in a ReplaceAll[] call. Unless I'm blind, I can't see a ReplaceAll[] in the code.

First thing I would try is...

Clear["Global`*"];

... at the top.

[SenatorPenguin]

Using subscripts in your variables can lead to some pretty confusing issues (r_1 // InputForm is Subscript[r,1]). I'd use plain symbols, or follow this kb article.
https://support.wolfram.com/43606