Computer Aided Design
Objectives
The main objectives of the Computer-Aided Design Course are:
1. To have an in-depth knowledge of the rules of Technical Drawing and Machine Drawing;
2. To understand and interpret 2D drawings correctly;
3. To be able to carry out detailed drawings of components and assemblies in CAD 2D software (bill-of-materials included);
4. To use CAD 3D software, in order to represent complex 3D parts and assemblies through parametric solid/surface modelling. To understand the concepts associated with the modelling of solids and surfaces using CAD 3D software.
5. To be able to create, edit and modify 3D parametric models of parts and assemblies, as well as to know how to measure and model components of machines also taking into account their assembly;
6. To be able to carry out CAD 3D modelling and CAD 2D drawings of mechanical elements and machines elements taking into account standardisation;
7. To understand the concepts of surface finish, dimensional tolerance, as well as geometric tolerance and to know how they are linked to the manufacturing processes. To know how to calculate tolerances taking into account standard adjustments recommended and to represent them through adequate symbology (CAD 2D);
8. To know the main welding processes used in the mechanical industry and to represent welded joints through adequate symbolic representation (CAD 2D);
9. To introduce the concepts of structural analysis by using the Finite Element Method (Solidworks Simulation) and reverse engineering (ScanTo3D).
10. To be able to print 3D parts using the FDM technique.
General characterization
Code
10633
Credits
6.0
Responsible teacher
António José Freire Mourão, Rui Fernando dos Santos Pereira Martins
Hours
Weekly - 5
Total - 70
Teaching language
Português
Prerequisites
NA
Bibliography
Cunha, Luís Veiga da, Desenho Técnico, Ed. Fundação Calouste Gulbenkian, 15ª Edição, ISBN: 972-31-1066-0, 2004, Lisboa
Silva, A., Ribeiro, C.T., Dias, J. e Luís Sousa, “Desenho Técnico Moderno”; 11ª Edição, Editora Lidel, ISBN: 978-972-757-337-0
Manfé, G., Pozza, R., Scarato, G., Desenho técnico mecânico : curso completo : vols. 1, 2, 3; trad. Carlos Antonio Lauand, São Paulo : Hemus-Livraria Editora
Simões Morais, J., Desenho Técnico Básico, ISBN: 978-972-965-252-3, Ed. Porto Editora, 2006
Américo Costa, Projeto 3D em SolidWorks, 1ª Edição, Editora FCA, ISBN: 978-972-722-820-1
Teaching method
The teaching method mainly used in the theoretical-practical classes is the oral exposition, accompanied with sketches, drawings, diagrams and resumes made by the teacher on the classroom’s board. Audiovisual media are also used for slide projection. During the resolution of exercises - involving freehand drawing and the use of CAD 3D and/or CAD 2D software, or, for instance, the calculation of tolerances - the teacher presents an exercise and solves it. Then, other exercises are presented, and the teacher defines a period for their resolution. The teacher tracks the progress of the exercise’s resolution and will attend and clarify any doubts arising during this period. After the allotted time, the teacher solves the exercises, explains them, and other solution approaches are discussed. The parts, assemblies and drawings are made by both the teacher and the students at the classroom’s computers.
The two projects to be carried out, one individual and one in teamwork, as well as the theoretical and practical test foreseen, will allow the students to review all the subjects taught during the semester and will allow the teachers to evaluate the knowledge acquired by the students, as well as the effectiveness of the transmission of knowledge.
Evaluation method
Thirty per cent (30%) of the final grade is obtained through one theoretical and practical test (TP) to be carried out by every student at the theoretical-practical classes of the 13th week of the semester. The grade will be rounded and approval on TP is dependent on obtaining a score of at least 9.50 (out of 20).
The final project (FP), which is mandatory, should be done by a maximum of 4 students per group, during nine weeks, and will count 40% for the final grade. The final project must only include parts and assemblies modelled after March 2022. At least ten different parts per student should be modelled. Each project should be presented (10 minutes) and discussed (10 minutes) with the teachers (mandatory; otherwise, a classification of zero (0) will be attributed to the Final Project).
The classification of the final project will take into account the quality and technical complexity of the modelled parts, the number of the modelled parts, the degree of complexity and effectiveness of assemblies carried out, the quality of the written report, as well as accuracy, technical quality and clarity of 2D drawings.
The final project must be sent by email to the teacher, which must contain the files of all modelled parts, all sub-assemblies and the final assembly, as well as three 2D drawings of three parts modelled, the 2D drawing of the sub-assemblies and the 2D drawing of the final assembly with the bill-of-materials. In addition, the final project’s report in a PDF format should also be sent.
A final project proposal must be delivered to the teacher by the end of the third week of the semester.
The third form of evaluation, which will count 30% to the final grade, will be the individual project, IP, which should be given to the teacher by the end of the seventh week of the semester. Considering the final project proposal submitted for approval, each student should make a CAD 2D drawing of a part (of intermediate complexity, >than 19 dimensions) that belongs to the final project that was, meanwhile, endorsed by the teacher. The 2D drawing should be printed and be given to the teacher.
The 2D drawings to be included in the final project report should be different from the drawings made by each student in the individual project.
The attendance, valid for one year, is obtained when the average of the final project (FP) and of the individual project (IP) is equal to or greater than 9.50 (out of 20). In order to get approval, the average of the final project (FP) and of the individual project (IP) should also be equal to or greater than 9.50 (out of 20).
The final grade (NF) is calculated according to the following formula:
NF = 0.3 x TP + 0.4 x FP + 0.3 x IP (for being approved NF> = 9.50)
Subject matter
1) Introduction to Computer-Aided Design (CAD3D and 2D): evolution, modelling and advantages. 2) General aspects of Technical Drawing: Standards, formats of papers, bill-of-materials, types of lines and their thicknesses, standard scales and writing. 3) Orthogonal projections. 4) Dimensions. 5) Creating, editing and modifying parametric CAD 3D models (solids and surfaces). 6) Detailed drawings, assembly drawing and revision of drawings, exploded view. 7) Drawing of machine elements and machine drawing according to standards. 8) Dimensional and geometrical tolerances. 9) Symbolic representation of surface finish and welding (CAD 2D). 10) Sheet metal technology. 11) Introduction to structural analysis by using the Finite Element Method (Solidworks Simulation) and Reverse Engineering (Solidworks ScanTo3D). 12) 3D printing.
Programs
Programs where the course is taught: