For Better Assembly Visualization, Try Combination States

Written By: Dave Martin
  • 4/12/2021
  • Read Time : 4 min.
Engine front view and exploded state.

In previous blog posts, we looked at combination states in the context of model-based definition (MBD). We use combination states to organize our 3D annotations to make them more readable and user-friendly. However, combination states have enormous capability for controlling the visualization of your models. In assemblies, these include:

  • Simplified Representations
  • Explode States
  • Cross Sections
  • Style States
  • Appearance States

I use combination states for images in presentations and reports (“viewgraph engineering”). Also, when I present a model in Creo in design reviews, I display the combination states in tabs at the bottom of the graphics area. A single click switches between one prepared view and another.

Simplified Representations

Other blog posts have discussed simplified representations as a large assembly management tool. You can control how much detail you bring into your computer’s RAM so it can operate more efficiently. Simplified representations can exclude components from view. This can be easier to manage than Hide and Layers to turn off the display of components.

Explode States

To communicate how the components in an assembly are put together, we can translate and rotate them from their final positions. In CAD, this is called an explode state. Furniture assembly instructions from Ikea are like explode states.


Exploded and cross-section view of engine.

Image: Explode state of an engine assembly in Creo.

Cross Section

To understand how a part needs to be manufactured, we want to see the interior wall thickness or cutaways of holes and voids. At the assembly level, we may want to see the components inside an enclosure. To do so, we may put a slice through the model using a plane or a sketch of straight lines. This is a cross section.

Cross-section view of engine.

Image: Cross section view in Creo.

Style States


You can display your model in various modes in Creo. These include wireframe, hidden line, no hidden line, shaded, and shaded with edges. When you have the model displayed in one of these modes, for clarity you can make individual components appear in other modes. The model could be shaded with edges, but exterior components could be in no hidden line display so people can see inside. This combination of display modes can be stored as a style state.


Appearance States

Each part model has its own defined appearance, which can be a color or a texture. Appearance states allow you to have multiple appearances applied to components in the assembly and choose which one is active.


Putting It All Together

A combination state consists of a saved orientation, any or all of these visualization states, 3D annotations, and more. In this way, a combination state gives you full control over managing the display of your models exactly how you want to communicate it and have others perceive it.

Exploded view of engine.

Image: A combination state incorporating multiple view states in Creo.

Additional Power

These combination states can be published to viewables that can be opened using Creo View. In this way, you can extend visualization across the enterprise. People downstream in the supply chain and in other groups like planning, sales, and marketing can view your combination states.

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About the Author

Dave Martin

Dave Martin is a Creo, Windchill, and PTC Mathcad instructor and consultant. He is the author of the books “Top Down Design in Creo Parametric,” “Design Intent in Creo Parametric,” and “Configuring Creo Parametric,” all available at He can be reached at

Dave currently works as the configuration manager for Elroy Air, which develops autonomous aerial vehicles for middle-mile delivery. Previous employers include Blue Origin, Amazon Prime Air, Amazon Lab126, and PTC. He holds a degree in Mechanical Engineering from MIT and is a former armor officer in the United States Army Reserves.