APS 111 NOTES
Chapter 1 Engineering Design
• Engineering Design
It is a systematic, intelligent process in which designers
generate, evaluate and specify designs for devices, systems
or processes whose forms and functions achieve clients’
objectives and users’ needs while satisfying a specified set
The shape and structure of something as distinguished
from its material.
The action for which a person or thing is specially fitted or
used or for which a thing exists.
Functions are what the designed device, system or process
is supposed to do, the actions that it must perform.
NOTE: Function can be deduced from form, but form can
not be deduced from function.
Something toward which effort is directed; an aim or end
Objectives are expressions of the attributes and behavior
that the client or potential users would like to see in a
designed system or device. They are normally expressed as
what the design should “be”.
The state of being checked, restricted, or compelled to
avoid or perform some action.
Constraints are restrictions or limitations on a behavior or
a value or some other aspect of a designed object’s performance.
An agency, instrument, or method used to attain an end.
Means or implementations are ways of executing those
functions that the design must perform.
A standard of measurement; in the context of engineering
design, a scale on which the achievement of a design’s
objectives can be measured and assessed.
A thing wanted or needed; thing essential to the existence
or occurrence of something else; in the context of
engineering design, engineering statements of the
functions that must be exhibited and the attributes that
must be displayed by a design.
• Engineering design problems are ill structured because
their solutions cannot normally be found by applying
mathematical formulas or algorithms in a routine or
Engineering design problems are open-ended because they
typically have several acceptable solutions.
• Concurrent Engineering
The process in which designers, manufacturing specialists,
and those concerned with the product’s life cycle (e.g.,
purchase, support, use and maintainence) work together,
along with other design stakeholders, so that they can
collectively and concurrently design the artifact together.
• Project Management
The process of achieving organizational goals by engaging
in the four major functions of planning, organizing,
leading and controlling. • Planning
The process of setting goals and deciding how best to
The process of allocating and arranging human and non
human resources so that plans can be carried out
The ongoing activity of exerting influence and using
power to motivate others to work toward reaching
The process of monitoring and regulating the progress of an organization
toward achieving its goals.
A one-time activity with a well defined set of desired end results.
Chapter 2 The Design Process
• The simplest descriptive model of the design process defines three
(i) Generation – The designers generates or creates various design
(ii) Evaluation – The designer tests the chosen design against
metrics that reflect the clients’ objectives and against requirements
that stipulate how the design must function.
(iii) Communication – The designer communicates the final design
to the client and to manufacturers or fabricators. • Five-Stage Descriptive Linear Model of Design Process.
Descriptive models describe the elements of the design process:
Pre: Client’s Problem Statement
(i) Problem Definition - A pre-processing stage that frames the
problem by clarifying the client’s original problem statement
before conceptual design begins.
(ii) Conceptual Design – Different concepts are generated to
achieve the client’s objectives.
(iii) Preliminary Design – Concepts are “fleshed out”, i.e; we hang
the meat of some preliminary choices upon the abstract bones of
the conceptual design.
(iv) Detailed Design – Choices from the preliminary design are
refined, articulating the final choice in far greater detail, down to
specific part type and dimensions.
(v) Design Communication – Identifies the work done after
detailed design to collect, organize, and present the final design
and its fabrication specifications.
Post: Documentation for Final Design
• Five-Stage Prescriptive Linear Model for Design Process.
Prescriptive models prescribe what must be done during the design
Pre: Client’s Problem Statement
(i) Problem Definition (Framing) – Clarify Objectives, establish
metrics for objectives, identify constraints and revise client’s
problem statement. (ii) Conceptual Design – Establish functions, establish
requirements (function specs), establish means for functions,
generate design alternatives and choose a design.
(iii) Preliminary Design – Model and analyze chosen design, test
and evaluate chosen design.
(iv) Detailed Design – Refine and optimize chosen design, and
assign and fix design details.
(v) Design Communication – Document final design.
Post: Documentation for final design (Reports, Drawings,
• Problem Definition
A pre-processing stage that frames the problem by clarifying the
client’s original problem statement before conceptual design
It is the process of feeding information about the output of a
process back into the process so it can be used to obtain better
results. It occurs in two notable ways during the design process.
(i) Internal feedback loops that come during the design process.
(ii) External feedback loop that comes after the design reaches its
Designers look at similar products that are already available and
try to evaluate how well those products perform certain functions
or exhibit certain features.
• Reverse Engineering (Dissection)
Designers dissect or take competitive products apart to determine why a given product or device was designed the way it was, with
the intention of finding better ways of performing the
same or similar sub-functions.
A prototype or a test unit embodies the principal functional
characteristics of the final design, even though it may not look at
all like the expected end product. They are very useful for lab
tests and simulations.
• The Four Phase Project Management Model
(i) Project Definition or Scoping – Developing an initial
understanding of the design problem and its associated project.
(ii) Project Framing – Developing and applying a plan to do the
(iii) Project Scheduling – Organizing the plan in light of time and
other resource constraints
(iv) Project Tracking, Evaluation and Control – Keeping track of
time work and cost.
• Five Stages of Group Development