Modelling and simulation
Modelling and simulation are good ways to check whether your design assembly works without all the hassle of building it.
Using a model or a simulation (for example, in Solidworks), you can easily and cheaply find the weaknesses or mistakes in your design.
Modelling and simulation each demonstrate different aspects of a design prior to the build. What are two aspects which modelling will that simulation won't, and visa versa?
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