Technical Drawing and CAD Concepts Quiz

Engineering Design and Material Selection Lecture 1

• The lecture is about Engineering Design and Material Selection, specifically the introduction and sketching.
• The instructors are Prof. Dr. Kristina Shea and Dr. Tino Stankovic.
• The lecture welcomes students to mechanical engineering.
• Images of various mechanical engineering designs were shown, including a boat, a medical device and a wind turbine.

Engineering Design: Basic Process

• This is a basic process for Engineering Design
• There are 5 stages:
  • Phase 0: Planning
  • Phase 1: Concept Development
  • Phase 2: System-Level Design
  • Phase 3: Detail Design
  • Phase 4: Testing & Refinement
  • Phase 5: Production Ramp-Up

Topic Overview

• The lecture covers multiple aspects of Engineering Design, which include:
  • Sketches
  • Technical Drawings
  • Computer-Assisted Design (CAD)
  • Additive Manufacturing
  • Sustainable Design
  • Design Process
  • Requirements
  • Ideation
  • Prototyping
  • Material Properties
  • Ashby Diagrams
  • Sustainable Materials
  • Working in Small Teams
  • 2D/3D Representations

Course Schedule

• The course schedule includes lectures and exercises.
• Each week has a specific topic.
• There are mandatory quizzes, and exercises.

Learning Objectives

• Students will learn to tackle design tasks, generate, evaluate, and select concepts and appropriate materials.
• Students will gain the ability to create and interpret technical drawings and 3D CAD models.
• The course will cover the interconnections between engineering design, manufacturing (additive), and material selection.
• Students will learn about medical, mobility, and sustainability problems presented in engineering.
• Hands-on exercises connected to real-life situations.

Course Information

• A weekly lecture schedule
• Weekly exercises are conducted through Moodle.
• Students will have 2 mandatory online quizzes that are graded and open book.
• Course fee of 14.- per student.

Exercises + Quizzes

• Hand in exercises to get feedback from tutors.
• Mandatory online quizzes are held in regular exercise sessions.
• The quizzes are closed-book.
• A maximum of one quiz can be missed and taken at another date if needed.
• Sample quiz on Moodle.

EDAC Team for EDMS

• The Instructors are Prof. Dr. Kristina Shea, for lectures and Moodle leader
• Andreas Walker who is the Moodle leader
• The Exercise leaders are:
  • Martin Schütz
  • Andreas Walker
  • Marc Wirth
  • Rafaela Louis
  • Maxime Escande

Course Relation to Bachelor Study

• The course connects with the Bachelor's program in Mechanical Engineering, covering topics including mechanics, machine design, innovation projects, engineering materials and production, focus projects, and various electives.
• The program is 6 semesters and totals 180 ECTS.
• It outlines all the subjects in each semester.

Learning Objectives – Lecture 1

• Gaining understanding about engineering design and the engineering design process.
• Understanding the need for a new mechanical ventilator and the basic design.
• Learning sketching fundamentals.
• Learning fundamentals of projections and views.

###Case Study on Health Introduction: A Mechanical Ventilator

• Current medical devices are expensive, break easily, and are not easy to maintain.
• Mechanical ventilators are needed in low-and middle-income countries, but there is often a shortage.
• There are around 0.14 ventilators for every 100,000 people in low-income countries, while there are 8–36 in Europe.

Principle of a Mechanical Ventilator

• Resuscitator bags are commonly used in manual resuscitation, are easily accessible, and are comparatively cheap.
• Automatic, cyclic compression of the bag using a mechanical ventilation system.
• Resuscitator bags can connect to standard and already accessible parts.
• The air pathway is already approved for medical use.

From a Need to a Product

• The diagrams show the progression from a sketch to several prototypes of a mechanical ventilator.

It takes an Interdisciplinary Team to...

• The mechanical ventilators were designed by a team (with the images) to address medical procedures, intuitive usability, robust hardware, and reliable controls.

What is needed to be a good engineer?

• Raw talent is important (either you have it or not).
• Hard work is essential.
• Learning is key.
• Knowledge of the latest technologies can help an engineer.

Conveying Ideas Graphically

• Devices for use with AMBU bags are shown graphically, explaining a device with a flexible squeeze bag and a curved outer surface.

Different Representations

• Various representations of the ventilator design are shown, including sketches, technical drawings, 3D models, and photorealistic renderings.

An Introduction to Sketching

• Sketching is a simple idea communication tool and is used in design concept phases
• Common tools are pen, pencil, or tablet.

Process from Mental Model to a Sketch

• The process of sketching includes defining goals, building a mental representation, selecting a representation mode, creating the sketch, validating the sketch.

Define Goals for Sketches

• The goals of creating sketches should be kept in mind when creating sketches, including defining what to show, who the target audience is and what the goal of the sketch is. Several types of sketches are presented

Projections: What do I want to show?

• Different viewpoints and projections of an object are shown.

Taxonomy of Projections

• Types of planar geometric projections (including Orthogonal, Axonometric, Oblique, and Perspective) are explained.

Perspective Projection

• Explanation of the perspective projection concept.

Sketching One and Two-Point Perspective Projections

• Illustration of one-point and two-point perspective projections.

Parallel Projection

• Explanation of the parallel projection concept.

Parallel vs Perspective Projection

• Comparison of parallel and perspective projections, including their application contexts.

Orthogonal Projection

• Explanation of orthogonal projections, showing top, front and side views

Axonometric Projections

• Explanation of Isometric, Dimetric, Trimetric, and Cavalier projections, focusing on axis ratios and angles.

Oblique Projections

• Explanation of Cavalier and Cabinet projections, focusing on axis and angles

Circular Shapes in Parallel Projections

Sketching Circles and Ellipses

Sketching Techniques

• Two approaches for sketching (Outline and Refine, Reduce to Basic Structure and Complete)

Example from Student Work

• Diagrams and descriptions are used to illustrate example problems and solutions from student work in the field of mechanical engineering, focusing on 'mechanized latrine emptying,' using a 'torpedo' approach.

Checklist for Validating Sketches

• Checklist with questions to evaluate sketch quality (object/function clarification, alignment with goals, technical soundness, perspective clarity, annotations, and overall satisfaction).

Validate: Scale and proportion

• Explanation of how to validate scale and proportions in sketches (using dimensions)

What is needed to be a good engineer?

• Multiple choice question about attributes of good engineers.

Engineering Design and Sketching: Wrap-up

• Summary of the key concepts covered in the lecture.

Exercise 1: Sketching and Engineering Design

• Questions about sketching objects (different shapes)

Stand up for respect!

Where does the joking end?

• Discusses mobbing, bullying, and sexual harassment, highlighting that these behaviors are not acceptable.

Where can I find help?

• Information on how to report disrespectful behavior and contact information for support

Ellipses and Circles

• Identifying when the shape is correctly shown

Overview of Key Elements in Engineering Design

• The diagram shows the relationship between the user, process, organization and product.

A Product Development Process

• Shows a product development process from the start to the end, covering 5 stages.

Phase 1: Concept Development

• Defining product requirements, generating concepts, and selecting for further development and testing.

Product Development – An Interdisciplinary Process

• Explains the interdisciplinary nature of product development and the importance of effective communication between engineers with different disciplines.

Requirement Definition

• Identifying and describing product requirements, including user-centric and solution-independent needs.

Which Device Fits Your Requirements?

• Choosing the proper charging device, given various criteria

Challenges of Understanding User Needs

• Discusses how user needs can be challenging to understand, and how to identify implicit needs, in addition to the importance of standards, norms and regulatory bodies.

Types of User Needs

• Discusses specific types of needs: explicit and latent, including the difficulties some users have expressing their needs in the latter.

Product Specifications: Motivation

• Defining product specifications and requirements to achieve success.

Product Specifications: What are they?

• Detailing the precise specifications of a product.

Product Specifications: Bicycle Example

Establishing Product Specifications

• Defining measurable user needs and how to specify them, using benchmarks and existing regulations.

Ideal and Marginal Values

• Defining ideal value and marginal value, and shows examples of how to specify criteria with examples.

Mechanical Ventilator: Product Goals

Technical Specifications

• Listing out specifications of the product.

Requirements can be very specific, i.e. to follow a curve

• Explains how requirements for product development can include detailed specifications about the product's behavior and functionality.

Concept Generation and Selection

• Discussing the methods of generating concepts include problem clarification, external research, internal research, systematic exploration and concept selection, and the process of going between stages for better results.

Clarify the Problem – Main Function and Functional Decomposition

• Identifying the central question from which a main function can be derived for a product to effectively solve the problem.

External Search – Look for Existing Concepts

External Search - Results for the Ventilator

• Presenting the results of external search.

Internal Search – Development of New Concepts

• Showcasing creativity techniques (such as making analogies, wish/wonder, and setting quantitative goals) to generate new designs

Related Stimuli

• Hand pumping of bag

Unrelated Stimuli

Creativity Methods – Brainwriting

• Explaining how brainwriting works in team design projects.

Explore Systematically – Concept Classification Tree

Explore Systematically – Concept Combination Table

Concept Combination Table – Concept Combination A

Concept Combination Table – Concept Combination B

Based on what you have learned so far: How would you approach the concept generation phase?

Concept Selection – Approaches

• Explain explicit and implicit concepts and selection methods

Concept Selection Method – Pugh Concept Screening Matrix

What are pitfalls of concept selection methods?

-Explaining when concept selection methods go wrong when certain behaviors/actions are made.

Concept Testing and Prototyping

• Explains the method of testing through user interviews and prototyping.

Mechanical Ventilator: Usability Study

• Summary of findings in a usability study of a mechanical ventilator with anesthesiologists.

Concept Generation and Selection – Wrap Up

• Summary of methods and concepts in concept generation and selection for design projects and design process

Exercise 2: Design and Concept Generation

• Questions about designing and generating concepts for a particular type of ventilator

Exercise 2: Design and Concept Generation - Tips for Teamwork/Tips for Creative Mood

• Tips for effective teamwork and improving creativity methods in a group.

Views

• Explanation of different types of views in a technical drawing

3D Model of a Mechanical Ventilator

• Shows an example 3D model of the mechanical ventilator.

Why Do We Need Technical Drawings?

Use of Technical Drawings in Product Development

• Showing examples of applying technical drawings in communication, manufacturing, testing and inspection, and maintenance and service stages of engineering products.

Technical Drawings Key Components

Technical Drawings: Main Shaft

• Showing example of main shaft technical drawing

Main Types of Views

First Angle Projection Method

Arranging Views: First Angle Projection Method

Third Angle Projection Method

Arranging Views: Third Angle Projection Method

Selecting Views: Use The Fewest Views Needed

Arranging Projections

Cover Plate: Which Additional Views Are Needed?

Better Solution: Section View

Final Result

Tips for Choosing Projected Views

• Tips for drawing optimal technical drawings.

Cuts and Sections

• Explaining different types of cuts and sections in technical drawings.

General Representation Rules II

• Explains general representation rules for drawing and dimensions.

Types of Sections

• Explaining different types of sections.

Hatching

Choice of Cuts

• Explanations and application illustrations of the usage of different cutting planes.

Second Example: Motor Holding Plate

Motor Holding Plate: Which View Should Be the Principal View?

Motor Holding Plate: Possible Orthogonal Projections

Showing What Is Inside: Hidden Lines

Showing What Is Inside: Cuts and Sections

More Complex Cutting Planes Are Possible

Tips for Sections

• Giving general direction for making cuts and sections

Final Drawing

Question: Which Section Cut is Shown?

Checklist for Verifying Your Technical Drawings

• Checklist for verifying technical drawings

Reading Technical Drawings: From 2D Back To 3D

Exercise 3: Projections and Cuts + CAD Intro

• Questions about projections and cutting.

Electric Mobility

Mechanical Systems are Highly Interdisciplinary

Introduction to Kyburz PLUS II

• Explains the structure of the Kyburz PLUS II, and its functionality.

CAD Model of the PLUS II: Exploded View

• Explains the parts of the PLUS II diagram.

Drivetrain

• Explores the drivetrain and the component parts.

Use of CAD Models in Product Development

• Explains various uses and applications of CAD models in product development by creating models from 2D concepts to testing and visualizing.

Types of Geometric Models

• Explaining the types of 3D geometric models, including wireframe, surface, and solid.

Which Body is Represented by this Wireframe Model?

Step 1

• Detailing how solid modeling systems work, with illustrations of basic solid primitives.

Step 2

• Detailing how solid modeling systems use Boolean operations.

3D Solid Models I: Different Modeling Steps

• Explaining the different solid modeling methods in technical diagrams, through step-by-step illustrations.

3D Solid Models II: Boundary Representation Model (B-rep)

• Explaining the boundary representation method (B-rep) and its applications.

Parametric Modeling

• Detailing why and how parametric modeling is used by creating links between geometric entities.

Sketch and Parametric Modeling – Overview

Sketching in CAD systems

• Explanations and methods used in CAD systems for 2D and 3D modeling

NX Sketching Example

Suggested CAD Sketching Process

• Presenting the sketching and drawing process in CAD systems.

Basic Sketch Geometry

Reference Sketch Plane Selection

Sketch Positioning

Constraints and Dimensions in Sketches

• Discussing constraints and dimensions in sketches

Constraining Sketches

• Explaining the constraints in sketches.

Modeling Operations

• Detailing modeling operations

Extrusion

• Describes how extruding works in CAD

Revolving

Sweeping

Example: Wheel hub from the PLUS II

Wheel hub modeling steps

Modeling operations: which statements are true?

CAD Introduction and Modeling Operations – Wrap-Up

• Summarizing CAD systems, models, and operations.

Design Task:

• A design task for a self-powered toy car and how to make it using 3D printing

3D Models

3D Surface Model

Representations: Analytic vs. Parametric

Basics: Control Points, Interpolation and Approximation

• Explanation about control points, interpolation and approximation in relation to curve and surface design.

Surface Models

• Definition of surface models.

Continuity between Curves and Surface Patches

Bézier Curves and Surfaces

• Explanation of Bézier curves and surfaces, including degree and control points

Question: Bézier curves

Bézier Curves – Summary

B-spline Curves

B-spline Curves - Examples 5 control points and for k = 3

• Discussing examples of B-spline and curves considering the different parameters

B-spline Curves - Examples 5 control points and for k = 2

• Discussing examples of B-spline and curves considering the different parameters

B-spline Curves - End-point Interpolation for 5 control points and for k = 3

• Discussing examples of B-spline point interpolation

B-spline Curves - Summary

Question: Which control point(s) Pi affect the segment p4(t) if k = 3?

• Question/answer about the specific segment in a B-spline curve.

Rational Curves

NURBS Curves and Surfaces

Lofting - Extrusion Based on Several Profiles

Creating Splines and Surfaces in NX (1)

Creating Splines and Surfaces in NX (2)

Creating Splines and Surfaces in NX (3)

Creating Splines and Surfaces in NX (4)

Continuity between Curves and Surface Patches