2.4.5 SetSymbols

The default symbols that appear in the solution rules returned by SolveMech can be changed with the SetSymbols function.

A model set-up function.

Default settings.

Because SetSymbols changes the behavior of all Mech functions that return symbolic expressions, SetSymbols must be run before building any other part of the mechanism model with SetBodies or SetConstraints. SetSymbols has the effect of executing ClearMech[].
The x, y, and z symbols are used by Modeler3D to represent angular velocities used in 3D velocity analysis, which is discussed in Chapter 4. The symbol is a Lagrange multiplier used in static and dynamic analysis, which is discussed in Chapter 7. The d symbol is used in 2D and 3D velocity analysis to symbolically represent differentiation.
If the current model is rebuilt with a new setting for SymbolBasis, the solution rules returned by SolveMech are changed accordingly.

This causes new symbols to be used in all subsequent models.

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The model is rebuilt with SetConstraints.

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This runs the model at crankangle = 0.5.

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This returns MechanicalSystems to its initial state.

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