Import Geometry

If you only have 2 minutes

Only STEP files (.stp / .step) are accepted. Prepare your geometry as clean, closed, watertight solid bodies before exporting. A model may contain several solids: keep parts that must stay physically separate, such as the bodies in a contact simulation, as separate solids.

Why STEP only?

• IGES lacks reliable solid definitions, causing open edges and gaps
• STL is purely triangulated surface data, no topology for FEM meshing
• Native CAD formats require proprietary licensed kernels

Preparing the geometry

Before exporting, create clean, coherent solid bodies without unnecessary details:

• Keep distinct parts as separate solids; never fuse bodies that interact through contact
• Remove superfluous surfaces, sketches, and construction geometry
• Avoid overlapping bodies and tapered zero-thickness surfaces
• Remove small details that aren't relevant to the analysis (fillets < mesh size, small holes)
• Verify units are set to millimetres

Combining fragments of one body

If your CAD system exports a single part as several disconnected fragments, combine them into one clean solid. Keep genuinely separate parts, such as contacting bodies, apart.

CAD system	How to combine
Autodesk Inventor	Combine bodies (Boolean union)
SolidWorks	"Combine" feature with "Add" operation
CATIA	Boolean operations + Part Cleanup
Siemens NX	Combine Bodies → Unite
Fusion 360	Modify → Combine
PTC Creo	Boolean → Merge
Onshape	Boolean → Union

Automatic healing

Dr.Q automatically detects and repairs minor geometry issues such as open edges, missing surfaces, and small overlaps. Significant problems trigger a warning: in that case, go back to your CAD system and repair the geometry there.

Common pitfalls

• Wrong units (geometry exported in metres instead of millimetres)
• Non-STEP format used
• Contacting parts fused into one solid, leaving no contact interface
• Construction geometry included in export
• Features too fine for the intended mesh size