When producing engineering output (3D Models, Detailed Drawings)
it is essential to be precise and adaptable to change. This is where parametric
modelling comes in handy.
Unlike with non-parametric design software (such as SketchUp,
Rhino or 3Ds Max), SOLIDWORKS geometry is built with relations and dimensions
in mind. This leads to easily editable shapes and sizes. A well-structured
sketch allows intelligent changes to be made with a few mouse clicks.
Take a look at this example of a house layout. The base of
the model is a sketch of straight lines with assigned dimensions. To resize the
rooms we simply drag the dimension handles and walls move maintaining the wall
thickness. Door width is linked to a single global value, changing it will
update all the doors immediately.
It is not just 2D layouts that are intelligent, same is
applicable to 3D commands such as Pattern. In the following welded structure
the roof trusses are patterned out from the middle. The pattern is parametric
and attempts to fit as many sections as it can with a predefined spacing. Increasing
the overall length of the structure increases the number of copied sections.
Try to increase the spacing and the number goes down. Tweak the model and get
multiple configurations within seconds.
Another advantage comes from the fact that geometry is
analytical and not faceted. Circles and arcs are infinitely round objects and
not polygons. This allows precise mass calculation and greatly helps with
dimensioning. To place a diameter there is no need to select two facet vertices
diametrically across from each other, simply pick the circle and diametric
dimension will pop out.
The video below shows how visual roundness of a circle is solely
dependent on the image quality setting, the actual circle is always regarded as
a circle by the system. It is easy to dimension various items with a single
command called Smart Dimension.
These are just the few advantages of parametric modelling.
And there are many more industry specific ones!