© 2011 Autodesk Automotive Surfacing Techniques with Autodesk ® Alias ® Surface Nils Kremser Major Accounts Automotive - Subject Matter Expert

© 2011 Autodesk Introduction & Agenda 110:15–10:30 “Automotive Shapes” What is different here? 210:30–10:50 Transitions & Continuity Terms and Differences 310:50–11:00 Surface Quality Criteria 411:00–11:25 Automotive Surfacing Techniques Workflow demonstration: Which tools are necessary? 511:25–11:30 Q&A Discussion

© 2011 Autodesk Automotive Shapes

© 2011 Autodesk Car Exteriors

© 2011 Autodesk Car Interiors

© 2011 Autodesk „Automotive“ shapes

© 2011 Autodesk What does „Freeform surface“ mean? source: Wikipedia: “Freeform surface modeling”

© 2011 Autodesk „Floating“ Shapes For Floating Highlights You need Perfect Transitions

© 2011 Autodesk Transitions & Continuity

© 2011 Autodesk Explaining terms: Radius Comb Radius plot:large radius = long comb

© 2011 Autodesk Explaining terms: Curvature Curvature plot:large curvature = long comb

© 2011 Autodesk Transitions & Continuity EXAMPLE

© 2011 Autodesk Transitions CAD Industrial Design ID / Automotive Tangent Curvature G3 continuity

© 2011 Autodesk CAD vs. Design shapes CAD Industrial DesignID / Automotive Tangent Curvature G3 continuity

© 2011 Autodesk CAD vs. Design shapes CAD Industrial Design ID / Automotive Tangent CurvatureG3 continuity

© 2011 Autodesk Surface Quality

© 2011 Autodesk Surface quality criteria 1.Number of Control Points: Fewer = Better! 3 point 4 points× 6 points ×

© 2011 Autodesk Surface quality criteria 1.Number of Control Points 2.CV distribution Proportional distances non-proportionally distances × All CVs follow positive shape CV does not follow positive shape ×

© 2011 Autodesk Surface quality criteria 1.Number of Control Points 2.Logical CV distribution 3.Internal G3 continuity (rate of change of curvature) Internal G3 continuity  Internal G3 break ×

© 2011 Autodesk Surface quality criteria 1.Number of Control Points 2.Logical CV distribution 3.Internal G3 continuity (rate of change of curvature) 4.Extendable extendable  not extendable ×

© 2011 Autodesk Surface quality criteria Single Surface: 1.Surface should be smooth: use just as few control points as needed! 2.Logical distribution of control points 3.Harmonic rate of change of curvature (internal G3 continuity) 4.Extendable Multiple Surfaces: 1.Highlights: surface transitions in required quality (depending on size and material)

© 2011 Autodesk Surface Quality Without Surface Quality emotions don‘t work!

© 2011 Autodesk Automotive Surfacing Techniques

© 2011 Autodesk Modeling Workflow Interior Data courtesy of EDAG

© 2011 Autodesk Modeling Workflow From Scan to Sections… … to centerline curves… … creating quickly surfaces EXAMPLE

© 2011 Autodesk Which Modeling Tools are needed? 1.Basic curve & surface creation and modification tools (draft / flange, square / rail / profile, revolve)

© 2011 Autodesk Which Modeling Tools are needed? 1.Basic curve & surface creation and modification tools 2.Modifying control points - move not only in x,y,z …

© 2011 Autodesk Which Modeling Tools are needed? 2.Modifying control points - move not only in x,y,z but also - in normal direction - slide along the hull curves (tangents) with lockable step size

© 2011 Autodesk Which Modeling Tools are needed? 3. Align (matching surfaces)

© 2011 Autodesk Which Modeling Tools are needed? 4. Fillet and Freeform Blend (with form factor)

© 2011 Autodesk Which Tools to analyse and diagnose are needed? 5. Managing sections and planes (x,y,z and radial sections, „true“ / normal section, interactive sections etc.)

© 2011 Autodesk Which Tools to analyse and diagnose are needed? 6. Diagnostics - Diagnostic Shaders (Zebra, iso-angle, Gauss etc.) - Highlight and Parting line analysis

© 2011 Autodesk Which Tools to analyse and diagnose are needed? 7. Visualization - photorealistic - but also technical (for design reviews, shutline discussions etc.)

© 2011 Autodesk Which Modeling Tools are needed - Summary 1.Curve & surface creation 2.Control point modification 3.Align (matching surfaces) 4.Sections and plane manager 5.Fillets / Blends 6.Diagnostics 7.Visualization

© 2011 Autodesk Learning Objectives At the end of this class, you will be able to:  understand better what is special in Automotive modeling  explain what “freeform surfaces” are  describe criteria for surface quality  describe different levels of surface continuity  know why a regular CAD system is not a sufficient tool for Automotive modeling  which modeling tools & features are needed

© 2011 Autodesk Thank you

© 2011 Autodesk Any questions?

© 2011 Autodesk Autodesk, AutoCAD* [*if/when mentioned in the pertinent material, followed by an alphabetical list of all other trademarks mentioned in the material] are registered trademarks or trademarks of Autodesk, Inc., and/or its subsidiaries and/or affiliates in the USA and/or other countries. All other brand names, product names, or trademarks belong to their respective holders. Autodesk reserves the right to alter product and services offerings, and specifications and pricing at any time without notice, and is not responsible for typographical or graphical errors that may appear in this document. © 2011 Autodesk, Inc. All rights reserved.