Academic Year 2023/2024 - Teacher: MICHELE CALI'

Expected Learning Outcomes

The student will acquire theoretical and practical skills in the field of 3D solid modelling. Know current computer-aided design techniques and methodologies in parametric solid modelling. Know how to use specific software for the design of mechanical components using integrated CAD-FEM, Multibody and CFD techniques.

Course Structure

Frontal teaching and use of specific software for integrated CAD-FEM, Multibody and CFD design.

Required Prerequisites

Knowledge of Industrial Technical Drawing, Linear Algebra and Geometry and the basics of mechanics.

Attendance of Lessons

Attendance obligation

Detailed Course Content

- Introduction to geometric modeling of machines. CAD in the design cycle. Comparison between conventional and CAD design approach. Generations of CAD systems and integrated CAD / CAE systems.

- Parametric forms and cubic polynomial curves. Geometric shapes in space. Lagrange's method and Hèrmite's method. Interpolating and approximating curves. The conditions of continuity.

- The Bèzier curves, the Bèzier cubic. The Splines, the cubic spline. The B-Splines, notes on NURBS. Graphical and analytical construction of a cubic polynomial curve.

- The mathematical description of surfaces applied to geometric modeling. The striped surfaces. The bilinear surfaces. The bicubic surfaces. The surfaces of Bèzier. The B-spline surfaces. Use of NURBS for the construction of a conic. The twist vector.

- Solid modeling techniques. Three-dimensional geometric modeling. Wire-Frame. Geometric data and topological data. Properties of r-sets. Operations on primitives. Solid construction geometry. Internal representation. Solids of revolution and extrusion. Bondary evaluation. B-Rep modeling. Topological structure. Outline of advanced modeling functions: blending, lofting, skinning, local operations, shelling, hollowing.

- Associative geometry. Acquisition of constraints. Parametric or procedural approach, variational approach. Mathematical expression of the constraints. Interactive systems.

- The solid modelers. Variable-driven. Features and feature-based modeling. Advanced modeling functions. Hybrid modelers.

- Virtual prototyping. The simulation of the product. Process simulation. Electronic data management. CAD / CAE modeling techniques

- Rapid prototyping.

- The integrated CAD / CAE design and the finite element method applied in the design of mechanical parts.

- The multibody methodology.

Textbook Information

a) Lecture notes

b) G. Farin, Curves and Surfaces for CAGD, a Practical Guide - Fifth Edition, Morgan Kaufmann Series in Computer Graphics.

c) F. Caputo, M. Martorelli, Disegno e progettazione per la gestione industriale, Ed. Scientifiche Italiane.

d) K. Lee, Principles of CAD/CAM/CAE Systems, Addison-Wesley.

e) C. Gianini, Ingegneria strutturale computazionale. Calcolo automatico di strutture meccaniche, Idelson - Gnocchi.

f) G. Manfé, R. Pozza, G. Scarato, Disegno Meccanico, Vol.I,II,III, Ed. Principato, Milano.

Learning Assessment

Learning Assessment Procedures

The oral test is intended to verify that the theoretical and practical knowledge and skills in the field of 3D solid modelling and integrated CAD-CAE design have been acquired.

The practical test is intended to verify knowledge of integrated CAD-FEM, Multibody and CFD techniques using the PTC Creo modeller.

Examples of frequently asked questions and / or exercises

 1 Parametric forms and polynomial curves;

 2 Lagrange's method and Hèrmite's method;

 3 Interpolating curves and approximating curves. Continuity conditions;

 4 Bèzier curves;

 5 The NURBS curves;

 6 The mathematical description of surfaces;

 7 The torsion vector;

 8 Solid modelling techniques;

 9 Operations on primitives;

 10 Constructive solid geometry;

 11 Modelling functions (blending, lofting, skinning, local operations, shelling, hollowing);

 12 Associative geometry. Parametric or procedural approach, variational approach;

 13 Solid modellers. Variable-driven. Features and feature-based modelling. Advanced modelling functions;

 14 CAD/CAE modelling techniques;

 15 Integrated CAD/CAE design;

 16 Finite element modelling techniques;

 17 Multibody modelling techniques;

 18 Rapid prototyping.