4. Model complexity

The complexity of a model depends on the degree of precision expected from the results. In general, what we expect from a model are trends or studies of sensitivities in relation to this or that parameter, rather than conclusions in relation to absolute values. We must therefore always take care to build a model that is just right, firstly because a heavy model requires powerful calculation tools, but also because interpreting the results is far more delicate. Let's take the example of the kinematic chain shown in figure 37 . We have adopted a 5-inertia model to study the main vibration modes we are likely to encounter. But let's imagine we're mainly interested in studying the...