Design Principles and processes for Cad applications

1. INDUSTRIAL
TECHNOLOGY
SECTION 2:
DESIGN
PRINCIPLES
AND
PROCESSES
BY
O.JACOBS

2. GENERAL OBJECTIVES
1. understand the design principles and
processes used in the development and
modification of
2. industry goods and services; and, apply the
design principles and processes used in
industries.

3. THE DESIGN PRINCIPLES
(a) Line, direction and style
(b) Shape and size
(c) Colour
(d) Texture
(e) Space.
(f) Form.

4. THE DESIGN PRINCIPLES
(a) Line, direction and style-
• A point extended becomes a line. Conceptually, a line
has length, but no width or depth.
• Whereas a point is by nature static, a line, in
describing the path of a point in motion, is capable of
visually expressing direction, movement, and growth.
• Style is a set of characteristics and features that make
a product, assembly, component, building or other
structure notable or historically identifiable.

5. THE DESIGN PRINCIPLES
(b) Shape and size-
Shape is the principal aspect by which we
identify and categorize forms. The characteristic
outline or surface configuration of a particular
form.
Size- The physical dimensions of length, width,
and depth of a form. While these dimensions
determine the proportions of a form, its scale is
determined by its size relative to other forms in
its context.

6. THE DESIGN PRINCIPLES
(c) Colour-
• A phenomenon of light and visual perception that
may be described in terms of an individual’s
perception of hue, saturation, and tonal value.
• Color is the attribute that most clearly
distinguishes a form from its environment. It also
affects the visual weight of a form.

7. THE DESIGN PRINCIPLES
(d) Texture-
• The visual and especially tactile quality given to a
surface by the size, shape, arrangement, and
proportions of the parts.
• Texture also determines the degree to which the
surfaces of a form reflect or absorb incident light.

8. THE DESIGN PRINCIPLES
(e) Space-
• an area or volume bounded actually or
theoretically
• a continuous extension in three dimensions

9. THE DESIGN PRINCIPLES
(f) Form-
• Form is the point of contact between mass and
space.
• Form is an inclusive term that has several
meanings. It may refer to an external
appearance that can be recognized, as that of a
chair or the human body that sits in it.

10. THE DESIGN ELEMENTS
(a) Line
(b) Colour.
(c) Shades.
(d) Hatching.

11. THE DESIGN ELEMENTS
(a) Line: weights and line types;
Line Weights and Uses
• Line weight refers to the blackness (intensity) and width of a line on the
drawing surface. In general, heavy (dark) lines are used to represent cutting
planes and contours (or outer boundaries) of and objects.
• Medium and lighter lines appear to be farther away from the viewer and are
used for secondary emphasis. Drawings for most design projects generally
use three line widths, thick (dark), medium, and thin (light). Thick lines are
generally twice as wide as thin lines, usually 1/32 inch or about 0.8 mm wide.
Thin lines are approximately 1/64 inch or 0.4 mm wide. Medium lines fall
between these two extremes.

12. LINE WEIGHTS

13. LINE TYPES
These are common line
types used in drawings to
describe objects, hidden
conditions, and the
importance of relationships
between components and
space.

14. THE DESIGN ELEMENTS
(b) Colour-
• Colour is an element consisting of hues, of which there
are three properties: hue, chroma or intensity, and value.
• Colour can be used to communicate concepts, ideas,
control movement (safety signs) or perception of depth,
time or space.
• Colour can aid organization so develop a colour strategy
and stay consistent with those colours. It can give
emphasis to create a hierarchy to the design of building

15. COLOUR
Use in Building and Electrical Engineering

16. COLOUR
Use Mechanical Engineering and Industry

17. THE DESIGN ELEMENTS
(c) Shades
• Light and Shade: Any abrupt shift in brightness
stimulates the perception of a spatial edge or
profile separated from a background surface by
some intervening space.
• This depth cue implies the existence of
overlapping shapes and the use of contrasting
tonal values in a drawing. Usually represented
through use of gradients in place of hatching.

18. SHADES

19. THE DESIGN ELEMENTS
(d) Hatching-
A combination of
lines used to
represent
materials, surfaces,
spaces or
boundaries in
industry.

20. THE DESIGN ELEMENTS
(d) Hatching examples-

21. THE DESIGN PROCESS
(a) Identifying the problem.
(b) Critical analysis of a problem.
(c) Generating alternative solutions.
(d) Selecting the best solution.
(e) Communication of the design ideas.
(f) Development of working drawings.
(g) Manufacture of the prototype/model (functions, ergonomics, material,
construction, economy, aesthetics, virtual).
(h) Testing and evaluation of the product.
(i) Codes and conventions (ISO and BS – British Standards).

22. THE DESIGN PROCESS
(a) Identifying the problem-
Methods:
• Interview
• Reports
• Review of Diagnostic data
• History
• Project brief
• Feasibility study

23. THE DESIGN PROCESS
(b) Critical analysis of a problem-
Methods:
• Brainstorming
• Compare similar Case study
• Checklists
• Assessment of required codes and standards
• List of tolerances/ constraints
• Story board

24. THE DESIGN PROCESS
(c) Generating alternative solutions-
Methods:
• Paper models
• Run virtual simulations by modifying tolerances/ constraints
• Modify schematic diagrams

25. THE DESIGN PROCESS
(d) Selecting the best solution
Methods:
• Checklists
• Mockup samples
• Application of codes and standards
• Analysis of simulation data
• Design brief
• Usage scenario

26. THE DESIGN PROCESS
(e) Communication of the design ideas-
Methods:
• Scaled drawings with annotations
• Process diagrams
• Wireless breadboard circuits
• Schematic circuit simulations
• Mock assemblies
• Castings/ clay sculptures

27. THE DESIGN PROCESS
(f) Development of working drawings-
Methods:
• Detailed plans including orthographic views and
projections, sections and elevations
• Schematic diagrams, wiring diagrams, line and block
diagrams
• Assembly drawings including orthographic views and
projections
• Exploded perspective views
• Constraints, tolerances, codes and standards guidelines

28. THE DESIGN PROCESS
(g) Manufacture of the prototype/model
• Functions- as both an outcome and a process. As an outcome, it
describes products that work well to perform their assigned tasks; as
a process, is a set of practices guided by the principles that produce
that positive outcome
• Ergonomics-the applied science that coordinates the design of
devices, systems, and environments with our physiological and
psychological capacities and requirements
• Material- anything including; metal, plastic, wood, glass, ceramics,
synthetic fibres, composites (made from two or more materials
combined together) used to create the prototype/model

29. THE DESIGN PROCESS
(g) Manufacture of the prototype/model continued
• Construction- is the process of creating a solution or architectural,
engineering and technical applications of the design; method of
producing physical scaled representation of working drawings.
• Economy- Commercial outcomes of the process; a balance
between cost and profit determined by the market/need.
• Aesthetics- is our perception or opinion of an object based on what
we see, feel, hear, smell and even taste.
• Virtual- computer aided simulation of concepts; represented by 3d
renderings/ animations, graphics or exploded views of assemblies.
Circuit Simulations.

30. THE DESIGN PROCESS
Prototype/Model
While the virtual model also allows a type of visual immediacy through the
rapid selection of views, these views are ultimately limited by the screen
size and the limitations of the software interface.

31. THE DESIGN PROCESS
(h) Testing and evaluation of the product.
Methods:
• Prototypes
• Experimentation
• Virtual Simulation
• Rendering
• Walk through
• Remediation ( fixing defects)
• Code and standard compliance check

32. THE DESIGN PROCESS
• Codes and conventions -these give recommendations for good
practice relative to design, manufacture, construction, installation and
maintenance with the main objectives of safety, quality, economy and
fitness for the intended purpose. Each code of practice number is
prefixed CP or BS.
• ISO -International Standards-these are prepared by the International
Organization for Standardization and are prefixed ISO. Many are
compatible with, complement and have superseded BSs, e.g. ISO 9001
Quality Management Systems and BS 5750: Quality Systems.
• BS – British Standards- these are publications issued by the British
Standards Institution which give recommended minimum standards for
materials, components, design and construction practices. These
recommendations are not legally enforceable but some of the Building
Regulations refer directly to specific British Standards and accept them
as deemed to satisfy provisions. All materials and components
complying with a particular British Standard are marked with the British
Standards kitemark thus: together with the appropriate BS number.

33. FACTORS THAT DETERMINE THE
APPROPRIATENESS OF A DESIGN
(a) Aesthetics.
(b) Functionality.
(c) Economics.
(d) Environment – resource conservation, environmental pollution.
(e) Ergonomics.
(f) Suitability of material.
(g) Innovation.
(h) Decoration.
(i) Anthropometrics.
(j) Selection of material.

34. FACTORS THAT DETERMINE THE
APPROPRIATENESS OF A DESIGN
(a) Aesthetics-
For industrial designers the aesthetic appeal of a product is often
top of the selection criteria. Internal and external finishes are
dependent upon the materials used.

35. FACTORS THAT DETERMINE THE
APPROPRIATENESS OF A DESIGN
(b) Functionality -
Purpose, designed chiefly from the point of view of use, whether
the building is functional from the viewpoint of the client is quickly
established; whether or not it is functional for the building users
will take a little longer to establish.

36. FACTORS THAT DETERMINE THE
APPROPRIATENESS OF A DESIGN
(c) Economics-
Financial factors. Good design is rarely possible within fees
offered by clients. Designers also make use of standard
components to reduce costs. Savings can also be made by
carefully selecting the best material and manufacturing process
for the item being designed.

37. FACTORS THAT DETERMINE THE
APPROPRIATENESS OF A DESIGN
(d) Environment – Resource Conservation, Environmental
Pollution
When designing products the designer must consider the effect
on pollution levels that their design will have. The product and its
manufacture may also be influenced by legislation which controls
pollution outputs. There has also been a major shift in public
interest in environmental issues and many people will take this
into account when purchasing a product.

38. FACTORS THAT DETERMINE THE
APPROPRIATENESS OF A DESIGN
(e) Ergonomics-
is the art and science of designing the work to fit the worker to
achieve
optimum productivity and cost efficiency, and minimum risk of
injury.

39. FACTORS THAT DETERMINE THE
APPROPRIATENESS OF A DESIGN
(f) Suitability of material-
When choosing the materials for a product the designer must
consider a number of factors
• use of product
• quantity to be manufactured
• market niche (cost)

40. FACTORS THAT DETERMINE THE
APPROPRIATENESS OF A DESIGN
(g) Innovation-
Products which appear on the market sometimes do so as the
result of technological innovation. Sometimes the new technology
has an obvious application and sometimes not. Sometimes
technology is transferred from one application to another.

41. FACTORS THAT DETERMINE THE
APPROPRIATENESS OF A DESIGN
(h) Decoration
The choice of finish of a product is influenced by similar factors to
those affecting the choice of materials, i.e.
• use of product
• quantity to be manufactured
• market niche

42. FACTORS THAT DETERMINE THE
APPROPRIATENESS OF A DESIGN
(i) Anthropometrics
Anthropometrics is the science concerned with the measurement
of humankind. Inevitably it is bound up with statistics, as people
vary considerably in most dimensions. Anthropometrics is of
crucial importance to architects as the ultimate basis of the design
of most buildings must be the size of the people using them.

43. FACTORS THAT DETERMINE THE
APPROPRIATENESS OF A DESIGN
(j) Selection of Material
The selection of material has to take into account how the
product/component will be used and what environment(s) it will
be used in.
Criteria:
• Purpose
• Properties
• Price
• Pollution
• Policy

44. USE THE PRINCIPLES, ELEMENTS
AND PROCESSES OF DESIGN
(a) Using sketches (manual or computer-aided)
To design a simple product in the areas of:
(i) Electrical and Electronic Technology;
(ii) Building and Furniture Technologies; and,
(iii) Mechanical Engineering Technology.

45. USE THE PRINCIPLES, ELEMENTS
AND PROCESSES OF DESIGN
(i) Electrical and Electronic Technology
Examples:
• Schematic drawings
• Line and block diagrams
• Installation drawings
• Wiring diagrams
• Component drawings

46. ELECTRICAL AND ELECTRONIC TECHNOLOGY

47. USE THE PRINCIPLES, ELEMENTS
AND PROCESSES OF DESIGN
(ii) Building and Furniture Technologies
Examples:
• Floor plans
• Elevations
• Furniture details
• Sectional details
• Framing plans
• Structural plans
• Drainage details

48. BUILDING SKETCHES

49. BUILDING SKETCHES

50. BUILDING SKETCHES

51. FURNITURE SKETCHES

52. USE THE PRINCIPLES, ELEMENTS
AND PROCESSES OF DESIGN
(iii) Mechanical Engineering Technology-
Examples:
• Arrangement drawing
• Assembly drawing
• Detail drawing
• Fabrication drawings
• Tender drawings
• Special detailed drawing
• Schematic drawing

53. MECHANICAL ENGINEERING SKETCHES
Assembly and Detail Drawings

54. USE THE PRINCIPLES, ELEMENTS
AND PROCESSES OF DESIGN
(b) Analyzing a simple manufactured product in the areas of:
(i) Electrical and Electronic Technology;
(ii) Building Technology;
(iii) Mechanical Engineering Technology; and,
(iv) Preparing the analysis report:
- findings (appropriateness of the design); and,
- recommendations.

55. PREPARING THE ANALYSIS
REPORT:
-APPROPRIATENESS OF THE
DESIGN
Analysis Report Content;
 an overview of your design
 your prototype sequence (if relevant)
 your testing procedures and results (if relevant)
 an assessment of your final design and its performance.

56. USE THE PRINCIPLES, ELEMENTS
AND PROCESSES OF DESIGN
Preparing the analysis report:
The purpose of the design report is to describe and justify the final
design (or for the intermediate reports the current status of the design).
The audience is primarily decision makers(technical and business
project managers) in your company and internal technical staff.
Tips
1) Take the active voice (use first person nouns and direct, forceful
verbs);
2) Use pronouns when recommending something, drawing conclusions,
or conveying
decisions;
3) Write the way you talk - make it easy for the reader to get your point;
4) Keep most sentences and paragraphs short.

57. SIMPLE ANALYSIS REPORT OUTLINE
1. Title Page
2. Executive Summary
3. Table of Contents
4. Design problem and
objectives:
5. Detailed design documentation
6. Bill of materials
7. Safety
8. Conclusions

58. SIMPLE ANALYSIS REPORT
OUTLINE
1. Title Page;
a)Date:
b)Subject/Topic:
c)Instructor:
d)Name/Team Members:
2. Executive Summary;
A. The purpose of the executive summary is to provide key information up-front,
such that while reading the report, a reader has expectations that are fulfilled on a
continuous basis. Key to a good Summary is the first sentence, which must
contain the most essential information that you wish to convey.
B. The summary is to be written as if the reader is totally uninformed about your
project and is not necessarily going to read the report itself.
C. It must include a short description of the project, the process and the results.
D. The Executive Summary is to be one page or less with one figure maximum.

59. SIMPLE ANALYSIS REPORT OUTLINE
3.Table of Contents: Include section titles and page numbers.
4.Design problem and objectives: Give a clear and concise definition of
the problem and the intended objectives. Outline the design constraints and
cost implications.
a)Include appropriate background on the project for the reader to be able to
put the information provided in context.
b)The final project objectives must also be presented in the form of a set of
technical specifications.

60. SIMPLE ANALYSIS REPORT OUTLINE
5. Detailed Design Documentation:
Show all elements of your design
including an explanation of:
A. Assumptions made, making sure to
justify your design decisions.
B. Function of the System
C. Ability of meet Engineering
Specifications
D. Prototypes developed, their testing
and results relative to Engineering
Specifications
E. Cost analysis
F. Manufacturing processes used
G. Human factors considered
H. All diagrams, figures and tables
should be accurately and clearly
labeled with meaningful names
and/or titles. When there are
numerous pages of computer-
generated data, it is preferable to
put this information in an appendix
with an explanation in the report
narrative.

61. SIMPLE ANALYSIS REPORT OUTLINE
Bill of materials: Parts costs include only those items included in the
final design. A detailed bill of materials includes (if possible) manufacturer,
part number, part description, supplier, quantity, and cost.
Safety : Provide a statement of the safety consideration in your proposed
design to the extent that is relevant.
Conclusions: Provide a reasoned listing of only the most significant
results.

62. RECOMMENDATIONS
Summarize what you have done and any recommendations for the
future (e.g. proposed improvements). Consider expressing these
using modal verbs such as ‘should’ or ‘must’.
Your design report is evidence of the extended work you’ve done to
reach your final design and convince your reader of its merits. Don’t
be tempted to overwhelm your reader with detail in the body of your
design report– instead, focus on the most useful and relevant
information for your audience

63. RECOMMENDATIONS
Criteria
• Set the context: Help the reader understand general information about the
problem or need
area, including any necessary definitions, statistics, etc. Use pictures and visual
images as
much as possible.
• Explain the purpose: why is this work important?
• Set the scope: How far can you or will you go to solve the problem?
• State the objectives: In short statements or a bullet list, identify the specific
objectives of your work - things that can be assessed at the end of the project
to determine if you were successful