Display Quality

By default the model display quality is set low to maximise graphics speed, this will result in an unrealistic display of your model surfaces, faceted curves, gaps between patches, etc.

To maximise display quality:

File > Options

Model Display > Shaded model display settings > Set shade quality to > 50

Model Display > Shaded model display settings > Shade very small surfaces

Entity Display > Geometry display settings > Edge quality display > Very High

Entity Display > Geometry display settings > Show smooth lines

Be aware this will increase the model file size significantly – particularly if you have a lot of small fillets. If this is an issue, reduce the quality and re-save your model.

 

Surface and Section Analysis

Much of the work in creating good surface models goes into fine tuning the curves and surfaces once they have been built.  There are various formal analysis tools available but don’t forget to use the most important one – your eyes.

Before you even start any analysis make sure you define what quality level is needed. Physically large auto body panel painted in a gloss black will show every deviation. A small electrical product in a matt finish or a product in a semi transparent low density polymer is not going to require the same level of quality

 

1800.analysis.tab

Sketcher

Many of our surface section curves will start as splines in a sketch (see Curvature and Splines).

Curvature analysis can be displayed in the general sketching environment through the Analysis tab but the analysis cannot be permanently displayed.

Whilst in the modify spline (Dbl click the spline) environment the analysis can be displayed while manipulating the spline. With the default scale the curvature plot generally doesn’t show clearly, increase to about 50.

1800.spline.mod.toolbar

 

Surface Selection

The selection filter – bottom right of window – defaults to Smart or All.  Is this mode you will have to Ctrl select the individual patches you want to analyse.  Change the filter to Quilt to select whole quilts.

 

Visual analysis

Always make a visual analysis the first level – ultimately, that’s all the consumer will do.  To make a good visual analysis of your surfaces need to be a dark, high gloss finish with a directional light.

1800.analysis_eye

Through the render toolbar, turn off the default ambient light.  Change the part colour to a dark colour with high reflectivity.

Also turn off your datum curves so they do not hide edges – if you have the lab config files installed there is a Mapkey setup to turn off – type ‘hc‘ – and turn on – type ‘sc‘ – curves.

 

Zebra stripes

Simulates a mirror finish on your part in a black and white stripe environment.  These stripes are then reflected across boundaries and you can visually check continuities.

1800.analysis_zebra

Here is an example of how this might look in reality. Consider the light horizontal reflection from the car door to the rear quarter panel and the highlights around the lock mechanism. In a CAD model these would have a perfectly smooth transition, pressed steel body panels have an acceptable fit quality according the the market position of the car.

1800.analysis.car.door

 

Section analysis

This tool with analyse the curvature of multiple cross sections.  We are looking for a smooth change in curvature along the section.

1800.analysis_sections.2

 

  • ico.curvature.analysis curvature icon in analysis toolbar
  • Ctrl pick the surfaces to be analysed
  • Select a planar surface or datum plane to which the cross sections will be parallel.
  • Change the number of sections and drag the position of the first and last section.
  • Adjust the scale of the curvature spines.

In the above image, point A shows the curvature is discontinuous, although the is a G1 connection (the spines point in the same direction at the junction) there is an abrupt change in curvature (spine length) – it is not curvature continuous – G2

Point B shows the curvature flips from convex to concave – curvature spines are placed on the convex side of a curve.

 

Gap and Flush Analysis 

Mainly used in automotive but certainly something to consider in larger consumer products where how flush adjacent components are and the gap between them has a significant effect on the final appearance.