Quiz 1 (Lectures 1-4)

Name the two planar geometric projections and their subcategories:

Name the two planar geometric projections and their subcategories:

Parallel vs perspective projections:

Parallel:

• used in technical drawings

• Elements with equal length are equally dimensioned

• Dimensions can be measured in drawings

Perspective:

• Closer to the eyes’ perception

• Elements with equal lengths can have different dimensions

• Used in “Photorealistic: rendering (design, architecture)

Name this projection method:

Perspective Projection

Name this projection method:

Perspective Projection - Orthogonal

Name this projection method:

Perspective Projection - Axonometric

Name this projection method:

Perspective Projection - Oblique

Name this projection method:

Parallel Projection

Name this projection method:

+ what happens if you were to move the vanishing points further / closer?

One- and two point perspective:

• if you move vanishing points further: object becomes more orthogonal (rectangular, perpendicular, forming right angles…)

• || closer: object becomes more skewed, looks as if observed from a close distance.

Name the two main sketching techniques:

• outline and refine (outside to inside)

• Reduce to basic structure and complete (inside to outside)

What are the most important sketching tips? (What to use / make / add / focus on)

• Use outlines

• Use meshing as an aid

• Preserve proportions

• Make cuts to show what is necessary

• Focus on important aspects

• Add comments and annotations

Checklist for sketching - important questions to ask yourself:

• is the object / function sketched clearly?

• Is the sketch aligned with the goals set?

• Is it technically sound and clean?

• Are the proportions and scale correct?

• Is the perspective clear?

• Are annotations needed to understand the sketch?

Sketching: Wrap-Up

Product Development Process:

Name the 6 Phases, as well as the purpose and tasks of phase 1:

Phase 1: Concept Development:

Purpose

• Define product requirements

• Generalize promising concepts and select one for further development and testing

Tasks include:

• Identify lead users and competitive products

• Collect user needs

• Define product requirements

• Develop alternative design concepts and select one

• Build and test concept prototypes

Requirement Definition: What are they exactly and why do we need them?

What are they exactly?

• Needs product should fulfill

• Explicit description of product’s desired form / functionality

• Solution is independent

  • Define the WHAT not the how. Should be as specific as possible.

Why do we need them?

• Effective communication, definition of goals / priorities / interface of product

• To capture user expectation in binding contract

• To ensure fitness of product for its intended use

What are the challenges in understanding user needs?

What are the three types of user needs?

Key Requirements when producing:

• Prototyping is very important, to also always go back and redefine initial requirements

Concept generation and selection - design process and stages:

• Design processes do not strictly move in one direction

• Jumps between stages could be useful and necessary

• Infinite loops should be avoided and a design decision should be considered to revise.

External Search - important steps for deigning and producing machinery / devices

• search already existing patents

• Determine the state-of-art (= state of newest technology)

• Search published literature

• Benchmark related products

• Interview lead users > Evaluate reactions

• Consult experts

Internal Search (Creativity Methods / Creating a concept combination table)

Creativity Methods

• Brainwriting, as many ideas as possible, plenty of sketches, no judgment  (Generate ideas in groups)

• Create a concept classification tree

Create a concept combination table

• Combine different partial solutions to find best combination

• Think about physical and geometric interfaces among partial solutions

• Refine partial solutions to derive solution / final concept

  • e.g. in classification tree: Blue: Concept combination A / Purple: Concept combination B

e.g. Ventilator (Picture)

Concept Selection - Explicit vs Implicit:

Explicit: Decision process, discussion

Implicit: Formulation of requirements, task description, favoring of established solutions, dominance of group members.

Concept Generation and Selection - Wrap-Up

Views - Name these projections

Name the main types of views

• Over-/under-dimensioning

Name the line types:

Name the 5 steps in the technical drawing process:

1. Chose the principle view

2. Chose other required views and cuts

3. Draw views and cuts

4. Add dimensions

5. Verify

Arranging Views - first vs third angle projection method:

Important to look out for when choosing projected views

• Most informative view is used as the principle view

• All details have to be shown in a technical drawing

• The object has to be presented without ambiguity

• Number of views should be limited to the minimum necessary

  • By reasonable choice of views

  • By using partial and special views

• Unnecessary repetition of details should be avoided

Cuts and sections including stepped view:

Name the three types of sections:

What are the three possible cut choices?

What is hatching? What does it look like?

Hatching: Using parallel lines to show the shape / direction / orientation of an object.

It can also help to differentiate different parts or materials of an object, as well as emphasize edges or contours.

Tips for cuts and sections:

• Cuts and sections allow insights into parts and assemblies to illustrate hidden geometries

• Cuts and sections have to be drawn and annoyed unambiguously

• Cute are almost always needed when there are holes in parts

• To avoid complex cuts, local sections can be used

Checklist to verify technical drawings: three questions:

1. Is principal view most informative view?

2. Are there sufficient views to fully define the geometry?

3. Are the smaller details clearly visible?

Projections and cuts - Wrap-Up:

What are elements of dimensioning? And what do we dimension for?

We dimension for:

• Function

• Manufacturing

• Inspection

6 steps of the dimensioning process:

1. Define outside dimensions

2. Define functional dimensions

3. Add required manufacturing dimensions

4. Add any dimensions for inspection

5. Add auxiliary dimensions

6. Verify the dimensioning

What are functional dimensions?

Functional dimensions define the shape, size and location of features that are relevant for the function of a part when assembled (into a final product). Whether a dimension is functional or not depends on the engineering context of the part. If a part is used in a different way, different dimensions may become functional

What are non-functional dimensions?

Non-functional dimensions define the form, size and position of other features, which are not important for the function of a part (when assembled into a final product). They are to be selected and indicated as most suitable for manufacturing and inspection.

What are auxiliary dimensions?

Auxiliary dimensions are just for information and serve to avoid calculations. They supplement functional and non-functional dimensions. They are added in parenthesis. They cannot have tolerances associated to them.

Dimensioning of special elements (Name two)

• You have to put angle and linear dimensions for bevels / countersinks.

Name the two arrangements of dimensions:

Arrangement of dimensions - what is pictured here:

Arrangement of dimensions - what is pictured here:

Internal / External Dimensions:

Dimensioning - Wrap-Up: