Next we need to use a computer algebra program to solve equations $(13)$ and $(16)$ for ${}_1^{\text{'}\text{'}},{}_2^{\text{'}\text{'}}$ in terms of ${}_1,{}_1^{\text{'}},{}_2,{}_2^{\text{'}}.$ Note that we also include the definitions given by equations $(1-4),$ so that we have $2$ equations $(13,16)$ and $2$ unknowns $({}_1^{\text{'}\text{'}},{}_2^{\text{'}\text{'}}).$ The result is somewhat complicated, but is easy enough to program into the computer.

These are the equations of motion for the double pendulumm.

tell me step by stem to cleate simulink model $($blocks diagram$)$

what the block i use and number of them and how connection between them