2.4.3 Initial Guesses

SetGuess serves both as an option for several Mech functions, and as a function for temporarily setting a model's initial guesses.

Various methods of setting initial guesses.

A SolveMech utility.

To advance the position for the model in large steps, it is sometimes necessary to specify a better initial guess than the current one. For example, to turn the crankshaft 3/4 of a turn at once, it might be necessary to set a new initial guess for 2 and Y3, the angular coordinate of the crankshaft and the height of the piston, respectively.

This runs the model at its initial position.

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This sets new guesses for 2 and Y3.

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This runs the model at 3/4 turn of the crank.

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If SetConstraints were to be run at this time with the default options, the initial guesses would remain at their current values, and . The SetGuess option resets the guesses to their defaults.

The SetGuess option resets the initial guesses.

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This shows the current guesses.

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