CADfix 12 Gets Clever with Your Geometry

CADfix geometry morphing automatically to create morphed CAD geometry using simulation results. (Image courtesy of ITI.)

CADfix 12, the latest version of International TechneGroup’s (ITI’s) computer-aided design (CAD) simplification, translation and repair software, has been released. The new release offers faster performance, GUI enhancements and a number of new tools for model comparison, defeaturing, virtual reality (VR) and more.

CADfix began its life as one of the first engineering analysis pre- and post-processors on the market, with an extensive set of geometry processing and advanced meshing tools. However, CADfix has shifted its focus since then to concentrate on CAD geometry, in particular its role in engineering analysis and striving for greater application integration and process automation.

“We see ourselves as having this very rich set of geometry tools that we can do some pretty clever things with,” said Andy Chinn, ITI managing director. “Everything that we’re doing with geometry handling is geared toward making models more useable, more meshable.” 

Making Models More Meshable

Mesh to CAD comparison in CADfix 12. (Image courtesy of ITI.)

CADfix 12 adds several new features to this rich set. One of the biggest additions is a new set of tools for geometry comparison. The first of these, the mesh to CAD comparison tool, allows a CAD model to be compared to its corresponding computer-aided engineering (CAE) mesh. This tool allows users to verify that their mesh accurately represents the CAD geometry. In the same vein, the new scan-to-CAD comparison tool allows users to compare CAD geometry to a 3D-scanned part. Finally, CADfix 12 offers a new CAD-to-CAD comparison tool that can find the differences between two CAD models and create a hybrid model using selected features from each.

In the interest of making better meshes, CADfix 12 adds three new tools to prepare a geometry for meshing. The first is an automatic splitting tool that can subdivide faces of a CAD model into quadrilateral regions. This allows meshing systems to more easily create high-quality meshes across the entire face. 

The new “Split faces into quads” tool in CADfix 12. (Image courtesy of ITI.)

The second new tool for geometry mesh preparation is the hex-skin partitioning tool for hybrid meshing. This tool will automatically partition a CAD model into regions suitable for more accurate hex meshing and regions better for faster tet meshing.

“There’s always this balance between whether you want a cheap and fast tet mesh or whether you want a fully structured high-quality hex mesh,” Chinn said. “The geometry partitioning tool allows you to split a CAD model up into different regions to which you can apply different meshing algorithms to get different mesh styles. It’s something that you wouldn’t be able to do if you were just treating the original geometry as one complete part.”

Auto hex-skin subdivision and hybrid meshing in CADfix 12. (image courtesy of ITI.)

The final mesh preparation tool new to CADfix 12 is Complex Zone Parametrization, a tool meant to get around problematic geometry like small sliver surfaces, fillets and detailed features. Rather than defeaturing the model, which can skew CAE results, the zone parametrization tool creates what Chinn describes as a virtual topology.

“Our zones are effectively a type of virtual topology,” he said. “They are a group of CAD surfaces that you join together such that you can mesh them without worrying about the internal edges that run between the faces. So, the nodes that get put on there are no longer constrained by those internal topological edges.”

Meshing across surface edges using a zoned parametrization in CADfix 12. (Image courtesy of ITI.)

Macros, Morphing and Virtual Reality

Another new feature in CADfix 12 is the Macro Record and Playback tool. In previous versions of CADfix, users looking to create an automated workflow were constrained to batch scripting. With the new macro tools, these same users can now approach scripting through the graphical user interface (GUI). Users can record a macro on a model, save it and edit it after the fact to add additional functionality. When playing back the macro, users can go through it step by step to see its effect on the model.

CADfix 12 approaches macros with the same geometric intelligence found throughout the program. A macro defined on one model may have trouble when applied to a different model. CADfix 12 addresses this concern with an automatic 3D comparison between the two models. This comparison identifies similar entities between the models and can map the correct entity to the macro during playback.

Screenshot of Macro Manager in CADfix 12. (Image courtesy of ITI.)

Capping off the new feature list for CADfix 12 is geometry morphing, another clever manipulation of geometry.

When doing a simulation on a model, engineers often look at the displacement field of their model under some set of conditions. Knowing what the part will look like under these conditions provides valuable insight into the real-world performance of the part. Engineers will often perform further simulation or design based on the deformation.

The new geometry morphing tool in CADfix 12 gives engineers the model they need to do this. The tool takes in both meshes—one for the original geometry and one for the deformed geometry—and can map the original model onto the deformed mesh. This automatically gives the user CAD geometry that matches the deformed results from the simulation, eliminating the need for manual rework of the original model.

The new geometry morphing tool in CADfix 12 automatically creates geometry from simulation results. (Image courtesy of ITI.)

Finally, CADfix 12 has added new export options that will appeal to developers working with VR and augmented reality (AR) applications. CADfix now has export support for FBX, OBJ, XGL and ZGL, all of which provide lightweight geometry for applications that demand quick and responsive rendering like VR.

“We're hoping to use a lot of the simplification repair technology to give better prepared models out to those VR systems,” Chinn said.

In addition to the new feature set, CADfix 12 boasts a large performance boost over CADfix 11, with a three to five times speed increase for most tools. The CAD import and export interfaces have also been updated to support the newest versions of CATIA V5, SOLIDWORKS 2018, Creo 5.0, and JT v9.0. CADfix 12 also introduces a new GUI layout.

CADfix 12 is now available. CADfix users with a Maintenance, Enhancement and Support (MES) plan will receive the update. For others interested in CADfix 12, visit the ITI website.

ITI has sponsored this post. They have no editorial input to this post. All opinions are mine. —Michael Alba