9.1.3 Solving for Multiple Parameters

Building coupled systems with multiple parameters.

Multiple parameter values are solved for by supplying an equal number of geometric conditions to be satisfied. A coupled system is used here to find the values of bar2 and bar3 that simultaneously cause the X coordinate of point 3 on the center bar to be 0.8 and the distance from the global origin to point 2 on the center bar to be 3.5, both at T = 0.1.

This finds the X coordinate of point 3 and the distance from the origin to point 2 at T = 0.1.

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This builds the CoupleSystem object.

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This solves the CoupleSystem object and finds new values for bar2 and bar3.

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This shows that the desired conditions have been satisfied.

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In all the preceding examples, the value of time T at which the coupled model has been solved has been taken from the default initial guess list. The Time option is used to explicitly set the value of time in the CoupleSystem object, or to specify that time is a dependent variable.

An option for SetCouple.

Instead of fixing time at 0.1, time can be a dependent variable to be solved for. The following example seeks the values of bar2 and T that satisfy the same pair of conditions that were used in the previous example.

The parameter bar3 is reset to its original value before building the new CoupleSystem.

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Here is the solution for T and bar2.

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The desired conditions are satisfied.

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