Course teached as: B024409 - INGEGNERIA INVERSA E PRODUZIONE ADDITIVA Second Cycle Degree in MECHANICAL ENGINEERING Curriculum MACCHINE
Teaching Language
italian
Course Content
-R.E. motivations, processes and technologies
-Processing of scanned data
-Geometry reconstruction from scanned data
-Practical demonstration of 3D scanners
-Practical demonstration of geometry reconstructions from 3D scanned data
-Practical examples and applications of R.E. techniques
-A.M. motivations and technologies
-The STL file format
-Polymeric materials
-A.M. Techniques
-Rapid Tooling
-Rapid Manufacturing
No reference books are available for the subjects of the course.
Support material consists of a set of slides used by the teacher during the lessons. Students will be provided with such material.
Learning Objectives
AQUIRED SKILLS
Part A: Reverse Engineering
Ability to cope with the issue of 3D model reconstruction of a real object by means of:
-choice of the most suitable 3D scanning device;
-definition of the necessary procedures for simplify/process the scanned data
-definition of the characteristics of the 3D model to be reconstructed and choice of the most suitable reconstruction technique.
Part B: Additive Manufacturing
Ability of pre-processing the CAD model of the starting object, in order to make it “usable” by the prototyping system.
Knowledge of the R.P. machines, techniques and of the respective usable materials.
Ability to define, for a given object to be built, the optimal R.P., rapid tooling and/or rapid manufacturing process.
CA4: Applying knowledge and understanding related to the implementation of engineering projects adapted to their level of knowledge and understanding, working in collaboration with engineers and non-engineers. The projects may concern components, equipment and mechanical systems of various kinds and for the widest possible applications.
CA5: Applying in-depth knowledge and understanding related to the choice and use of appropriate equipment, tools, procedures and methods, knowing their limits and potential; in particular the ability to conduct even complex experiments, manage and employ advanced instrumentation and software, with appropriate analytical capabilities.
CA6: Applying knowledge and understanding related to the identification, location and retrieval of data and information necessary for the assessment.
CA7: Applying knowledge and understanding related to the definition, design and implementation of researches useful for understanding problems, through the use of both theoretical and experimental models and techniques.
CA9: Applying knowledge and understanding related to the critically assessment of data and results, drawing appropriate conclusions, aware of the degree of uncertainty that may affect them.
CA12: Applying adequate knowledge and understanding to understand English texts.
CA15: Applying knowledge and understanding to achieve adequate preparation for tertiary level university studies (frequency to post-master's degree courses and doctoral schools) in order to further deepen knowledge and skills in research.
CC2: In-depth knowledge and understanding of the theoretical-scientific aspects of mathematics and other basic sciences. To be able to use this knowledge to interpret and describe complex and/or interdisciplinary engineering problems.
CC5: Knowledge and understanding of materials and their behaviour in the various loading conditions found in design practice. Methods for characterising material behavior.
Prerequisites
Base knowledge of Computer Aided Design and manufacturing technologies
Teaching Methods
Part A: Reverse Engineering
The first part of the program is dedicated to theory and practice of devices and techniques for R.E.; the second deals with practical demonstrations of 3D scanning machines and real case studies.
Part B: Additive Manufacturing
Most of the lessons are dedicated to the presentation of A.M. technologies (machines and processes); afterwards some practical demonstrations, about the CAD model processing and the definition of process parameters, will be provided.
Further information
In order to take the exam, please register to:
http://sol.unifi.it/prenot/prenot
Type of Assessment
The learning verification test consists of a written test with open questions and exercises. In particular, 2 questions/exercises relating to additive manufacturing processes (description of technologies, problems, processes); 4 questions/exercises relating to reverse engineering processes (description of technologies, processes, problems encountered). The student will have to demonstrate good knowledge of 3D additive manufacturing and scanning technologies; good knowledge of the preparation processes of 3D models for physical realization; good knowledge of the general process of Reverse Engineering; sufficient knowledge of the procedures for extracting geometric parameters from the measured raw data; sufficient knowledge of the procedures for the extraction of geometric parameters from the measured raw data; sufficient knowledge of the sources of error that characterize additive manufacturing and reverse engineering (ca4, ca5, ca6, ca7, ca9, ca12, ca15, cc2, cc5).
Course program
Part A: Reverse Engineering
1. R.E. motivations and application fields
2. R.E. process definition
3. Introduction to R.E. technologies
4. Classification of 3D scanning methodologies
5. Contact systems
a. general characteristics
b. active systems
c. passive systems
d. point mode and scanning mode acquisition
e. scanning strategies and possible error sources
6. No contact systems
a. general characteristics
b. optical systems
i. introduction to cameras and epipolar geometry
ii. calibration of a set of cameras
iii. passive optical systems
1. passive stereo-vision
2. shape from shading
3. shape from texture
4. shape from focus-defocus
5. shape from silhouette
iv. active optical systems
1. laser-camera triangulation
2. active stereo-vision (laser and structured light)
3. time of flight scanning
7. Pre processing of scanned data
a. overlapping and oversampling
b. simplification and registration of point clouds
i. techniques for scan lines
ii. techniques for 2.5 D point clouds
iii. techniques for 3D point clouds
c. error sources and dimensional assessment
8. 3D modeling: geometry reconstruction starting from scanned data
a. tessellation and triangulation
b. reconstruction by means of primitives and features
c. reconstruction by means of sections
d. reconstruction by means of surface patches
9. Practical demonstrations of a series of 3D scanners
10. Practical demonstrations of geometry reconstructions of objects starting from scanned data
11. Case studies
Part B: Additive Manufacturing
1. R.P. Motivations and application fields
2. Introduction to A.M. technologies
3. A.M. techniques classification
4. The STereoLithography Interface Format (STL)
a. file content description
b. geometry errors management and dedicated software packages
5. Polymeric materials
6. A.M. Techniques; processes, machines, materials
a. Stereolithography (SLA)
b. Solid Ground curing (SGC)
c. Fused Deposition Modelling (FDM)
d. Laminated Object Manufacturing (LOM)
e. Selective Laser Sintering (SLS)
f. Polyjet method
g. Three Dimensional Printing (3DP)
h. Multi Jet Modelling (MJM)
i. Ballistic Particle Manufacturing (BPM)
l. Drop On Demand (DOP)
h. A.M. with metal material
i. Selective Laser Melting (SLM)
ii. Electron Beam Melting (EBM)
iii. Laser Engineered Net Shaping (LENS)
7. Rapid Tooling