MECH292 Quiz 1

Why study the design process?

Why study the design process?

1. need; 2. complexity; 3. cost and poor design: 85% of problems due to design process

Systemization can ensure…

best ideas will be generated

three measures of the effectiveness of the design processs:

cost(design can change cost by 50%), quality, and time

1980 Xerox realized 50% cheaper copier alternative was attributed to…

10% materials, 15% tooling and processing, 25% design

Quality cannot be built into a product unless…

it is designed into it

Changes occuring late in the design process are ___ ___ than those occurring earlier

more expensive

design process is also the ____ of people and the ______ they develop in the evolution of a product

management, information

Over-The-Wall (sequential) design method

customers → marketing → engineering design → production

Concurrent engineering

simultaneous engineering(parallel vs serial) also called integrated product design

primary focus of integrated product design

integration of teams of people having a stake in the product, cause developer to consider all elements of the product lifecycle from concept through disposal

concurrent engineering key words

product life, stake holders, product requirements, concept generation, communication

Life of a product

1. development of the product, 2. manufacturing, 3. delivery, 4. retirement

analytic problem

need to find correct formula and plug in the correct values, theres is only one correct answer

synthetic problem

ill-defined, several possible solutions

Goal in design

find a good solution(compromise) that leads to a quality product with least commitment of time and other resources, most design problems have multiple solutions

basic actions of problem solving

1. establish the need to be solved, 2. understand the problem, 3. plan how to solve , 4. generate alternatives, 5. evaluate alternatives, 6. decide solution, 7. communicate results

system

collection of objects that perform a specific function

assembly can be decomposed in….

parts or components

what is considered first in design?

function of the system and its decomposition

most common devices are cataloged by their….

function

function:

desired output

behavior:

actual output

performance:

measure of function and behavior

Most design problems of the industry are for…

redesign(optimization)

languages of design-semantic

verbal or textual representation of the object

languages of design-graphical

drawings of the object, GDT

languages of design-analytical

equations, rules, or procedures representing form or function of the object

languages of design-physical

the hardware or actual physical object

refinement

making an object less abstract

solving design problems is a…

decision making process

there is approximately one decision made each ___ during design activity

minute

cognitive psychology

study of human problem-solving abilities

Random access memory (RAM):

short term memory

Read-only memory(ROM):

long term memory

What brings information from the environment in information processing?

sensors:eyes, ears, and hand

General knowledge:

information that most people know and apply

domain specific knowledge:

information on the form or function of an individual object

Estimated that it takes ____ to gain enough specific knowledge to be considered an expert in a domain

10 years

Feature is synonymous with what in mech. eng. ?

chunks of information

quickness:

information chunks can be processed in the short term memory in about 0.1 seconds

The Magical Number Seven

reported that the short term memory is limited to seven chunks of information

long term memory is slow:

takes 2-5 minutes to memorize a chunk of information

three-step approach to generating solution:

decompose the problem, find partial solutions to sub problems, recombine sub solutions

Evaluation requires 2 actions:

comparison and decision

comparison necessitates…

modeling the concept for performance evaluation

decision requires…

a measure

2 criteria for a creative solution:

1. must solve the problem, 2. must be original

creative designer is generally a person of….

normal intelligence, a visualizer, a hard worker, and a constructive nonconformist

creativity =

surprise + originality + beauty + Utility

creativity measured by….

flexibility, originality, fluency, elaboration

flexibility:

change in the type of response

originality:

how unique are the responses

fluency:

the number of quick responses

elaboration:

the addition of details

two sources for design projects

market or development of new technology

what percent of new product design is market-driven

80%

two aspects of design process

method/structure implies rigidity and creativity/flexibility implies freedom

who said “genius is 1% inspiration and 99% perspiration”

Thomas Edison

how many registered patents did Thomas Edison have?

1093

How many parts in the space shuttle?

10 times more than boeing 747, more 2.5 million parts

Boosters needed to be disassembled for space shuttle so needed to develop….

field joints to fasten segments together

When did the space shuttle Challenger explode?

January 28, 1986

Why did the space shuttle explode?

failure of an O-ring seal in a field joint

by what means were the booster segments joined?

tang-and-clevis arrangement

What kept the joint from being redesigned for the Space Shuttle?

time pressures and cost

The Space shuttle joint design was based on those from the….

Titan III rocket

Difference between challenger and Titan rocket design:

challenger booster was larger in diameter, multiple use, its o-rings took pressure of the combustion, its tang was longer and flexed more, its o-rings were glued instead of molded

When was the Columbia Catastrophe

February 1st, 2003

design notebook

diary of the design activities

design reviews

periodic presentations to managers, customers, and other team members

goal of systematic design

set out a comprehensive design methodology for all phases of the product planning, design and development process for technical systems

Who developed systematic design?

Gerhard Pahl and Wolfgang Beitz

systematic design:

developed in germany after WWII, easy to learn and adopt(natural sequence), step-by-step, can be used to measure progress, each step supported by multiple design tools

Systematic design steps

clarification of task, conceptual design, design embodiment, detailed design

systematic design-Clarification of task

collect information, clarify task, formulate specifications

systematic design-conceptual design

identify essential problems, functional decomposition, solutions for sub-functions, combine solutions

systematic design-design embodiment

preliminary layout and form, choose best option, check for form, fit, and function

TRIZ:

Theory of Inventive Problem Solving developed in 1946-1985 by Altshuller, Russia

four basic steps of TRIZ

define specific problem, find the TRIZ generalized solution, adapt generalized solution to solve specific problem

Combine working principles into working structures according to….

geometric adn physical compatibility

embody

give concrete form to something

embodiment

comprehensive organization, incarnation, incorporation, representation in material form

which principles are used in design embodiment

mechanics, structures, and materials technology

preliminary layouts and form designs…

must meet spatial constraints and fulfill main functions

activity of planning results in a….

blueprint for a process

____ and ____ are often used interchangeably in industry

plan, process

progress in a design project is measured by deliverables such as…

drawings, reports, prototypes, bills of materials

Why are prototypes important?

the provide proof of concept, product, process, and production

five steps in planning:

identify tasks, state objective for each task, estimate resources needed, develop sequence for tasks(Gantt Chart), estimate cost