Definition-various methods and forms of
design-importance of product design-static
and dynamic products-various design projects-
morphology of design-requirements of a good
design-concurrent engineering-computer
aided engineering-codes and standards-
product and process cycles-bench marking.
UNIT
1
What is design?
• Engineers are not the only people who design things, it is true
that the professional practice of engineering is largely
concerned with design; it is often said that design is the
essence of engineering.
• To design is to pull together something new or to arrange
existing things in a new way to satisfy a recognized need of
society.
Definition
“Design establishes and defines solutions to and pertinent
structures for problems not solved before, or new solutions to
problems which have previously been solved in a different
way.”
The ability to design is both a science and an art.
The science can be learned through techniques and methods
to be covered in this text, but the art is best learned by doing
design.
Design should not be confused with discovery.
Discovery is getting the first sight of, or the first knowledge of
something, as
When Columbus discovered America or Jack Kilby made the
first microprocessor. We can discover what has already existed
but has not been known before, but a design is the product of
planning and work.
Design may or may not involve invention .
To obtain a legal patent on an invention requires that the
design be a step beyond the limits of the existing knowledge
(beyond the state of the art). Some designs are truly
inventive, but most are not.
Good design requires both analysis and synthesis
Analysis :
• To understand how the part will perform in service.
• To calculate as much about the part’s expected behavior as
possible before it exists in physical form by using the
appropriate disciplines of science and engineering science
and the necessary computational tools.
• It usually involves the simplification of the real world through
models.
Synthesis :
• It involves the identification of the design elements that will
comprise the product, its decomposition into parts, and the
combination of the part solutions into a total workable
system.
Definition-various methods and forms of
design-importance of product design-static
and dynamic products-various design projects-
morphology of design-requirements of a good
design-concurrent engineering-computer
aided engineering-codes and standards-
product and process cycles-bench marking.
UNIT
1
TYPES OF DESIGNS/DIFFERENT FORMS OF DESIGN
1. Original Design/Innovative Design
2. Adaptive Design
3. Redesign/Variant design
4. Selection Design
5. Industrial Design
1. Original Design/Innovative Design
• Original design involves Invention
• Successful original designs occur rarely
• Usually disrupt existing markets
• It seeds of new technology of far-reaching
consequences
• Example : Design of the microprocessor
2. Adaptive Design
• Design team adapts a known solution to
satisfy a different need to produce a novel
application.
• For example, adapting the ink-jet printing
concept to spray binder to hold particles in
place in a rapid prototyping machine.
• Adaptive designs involve synthesis and are
relatively common in design.
3. Redesign/Variant design
• Engineering design is employed to improve an
existing design.
• Product that is failing in service/reduce its cost
of manufacture.
• Without any change in the working principle or
concept of the original design.
• For example, the shape may be changed to
reduce a stress concentration, or a new
material substituted to reduce weight or cost.
4. Selection Design
• Most designs employ standard components
such as bearings, small motors, or pumps.
• Supplied by vendors specializing in their
manufacture and sale.
• Selecting the components with the needed
performance, quality, and cost from the
catalogs of potential vendors.
5. Industrial Design
• Improving the appeal of a product to the
human senses, especially its visual appeal
• This type of design is more artistic than
engineering
• How the human user can best interface with
the product
Definition-various methods and forms of
design-importance of product design-static
and dynamic products-various design projects-
morphology of design-requirements of a good
design-concurrent engineering-computer
aided engineering-codes and standards-
product and process cycles-bench marking.
UNIT
1
• Refrigerators, Power tools, or DVD players, or
• Highly complex products such as a missile system
or a jet transport plane.
• Electrical power generating station or a
petrochemical plant, design of a building or a bridge
Decisions made in the design process cost very little in terms of the overall
product cost but have a major effect on the cost of the product
You cannot compensate in manufacturing for defects introduced in the
design phase
The design process should be conducted so as to develop quality, cost-
competitive products in the shortest time possible
Definition-various methods and forms of
design-importance of product design-static
and dynamic products-various design projects-
morphology of design-requirements of a good
design-concurrent engineering-computer
aided engineering-codes and standards-
product and process cycles-bench marking.
UNIT
1
Product innovation
• Introducing a new screen size for TVs
• Changing from a CRT TV to a flat screen
• Adding functionality such as Internet access to TVs
Process innovation
• Building new systems that assemble a TV set faster and cheaper
• Redesigning the assembly line so that TVs can be manufactured more
reliably
• Outsourcing the production of the plastic covers on TVs so costs can be
reduced and quality improved
Service innovation
• Changing the way dealers sell new TVs in order to cut costs
• Changing the way customers get rid of their old TVs by introducing a take-
back policy
• Offering credit finance options to allow customers to purchase TVs
Definition-various methods and forms of
design-importance of product design-static
and dynamic products-various design projects-
morphology of design-requirements of a good
design-concurrent engineering-computer
aided engineering-codes and standards-
product and process cycles-bench marking.
UNIT
1
Identification of customer needs
Problem definition
Gathering information
Conceptualization
Concept selection
Refinement of the PDS
Design review
Detailed engineering drawings suitable for manufacturing.
Routinely these are computer-generated drawings, and they
often include three-dimensional CAD models.
Verification testing of prototypes is successfully completed and
verification data is submitted. All critical-to-quality parameters
are confirmed to be under control.
Usually the building and testing of several preproduction
versions of the product will be accomplished.
Assembly drawings and assembly instructions also will be
completed. The bill of materials for all assemblies will be
completed.
A detailed product specification, updated with all the changes
made since the conceptual design phase, will be prepared.
Decisions on whether to make each part internally or to buy
from an external supplier will be made.
With the preceding information, a detailed cost estimate for
the product will be carried out.
Finally, detail design concludes with a design review before the
decision is made to pass the design information on to
manufacturing.
Phase IV. Planning for manufacture
Designing specialized tools and fixtures Specifying the
production plant that will be used (or designing a new plant) and
laying out the production lines
Planning the work schedules and inventory controls (production
control)
Planning the quality assurance system
Establishing the standard time and labor costs for each operation
Establishing the system of information flow necessary to control
the manufacturing operation
Phase V. Planning for Distribution
Important technical and business decisions must be made to
provide for the effective distribution to the consumer of the
products
Shipping package may be critical
The economic success of the design often depends on the
skill exercised in marketing the product
If it is a consumer product, the sales effort is concentrated on
advertising in print and video media.
Highly technical products may require that the marketing step
be a technical activity supported by specialized sales brochures
Phase VI. Planning for Use
consumer-oriented issues must be considered in the design
process at its very beginning
The following specific topics can be identified as being
important user-oriented concerns in the design process:
– Ease of maintenance, Durability,
– Reliability, Product safety,
– Convenience ,in use (human factors engineering),
– Aesthetic appeal, and Economy of operation
Phase VII. Planning for Retirement
of the Product
Disposal of the product when it has reached the end of its useful
life
In the past, little attention has been given in the design process to
product retirement.
This is rapidly changing, as people the world over are becoming
concerned about environmental issues. There is concern with
depletion of mineral and energy resources and with pollution of
the air, water, and land as a result of manufacturing and
technology advancement
Design for the environment , also called green design, has become
an important consideration in design
The design of a product should include a plan for either its disposal
in an environmentally safe way or, better, the recycling of its
materials or the remanufacture or reuse of its components
Definition-various methods and forms of
design-importance of product design-static
and dynamic products-various design projects-
morphology of design-requirements of a good
design-concurrent engineering-computer
aided engineering-codes and standards-
product and process cycles-bench marking.
UNIT
1
Requirements of a Good Design
• A product is usually made up of a collection of parts,
sometimes called piece parts. A part is a single piece requiring
no assembly. When two or more parts are joined it is called an
assembly. Often large assemblies are composed of a collection
of smaller assemblies called subassemblies . A similar term for
part is component.
• Performance requirements can be divided into primary
Functional requirements and complementary performance
requirements.
• Functional requirements: such as forces, strength, deflection,
or energy or power output or consumption.
• Complementary performance requirements : such as the
useful life of the design, its robustness to factors occurring in
the service environment, its reliability, and ease, economy, and
safety of maintenance.
Environmental requirements:
• The first concerns the service conditions under which the
product must operate. The extremes of temperature,
humidity, corrosive conditions, dirt, vibration, and noise, must
be predicted and allowed for in the design.
• The second aspect of environmental requirements pertains to
how the product will behave with regard to maintaining a safe
and clean environment, that is, green design.
Aesthetic requirements refer to “the sense of the beautiful.”
• They are concerned with how the product is perceived by a
customer because of its shape, color, surface texture, and
also such factors as balance, unity, and interest.
The final major design requirement is cost.
• Product development cost, initial product cost, life cycle
product cost, tooling cost, and return on investment.
Definition-various methods and forms of
design-importance of product design-static
and dynamic products-various design projects-
morphology of design-requirements of a good
design-concurrent engineering-computer
aided engineering-codes and standards-
product and process cycles-bench marking.
UNIT
1
Definition of Concurrent Engineering
"Concurrent engineering is a systematic approach to the integrated,
concurrent design of products and their related processes, including
manufacture and support. Typically, concurrent engineering involves the
formation of cross-functional teams, which allows engineers and managers of
different disciplines to work together simultaneously in developing product and
process design. This approach is intended to cause the developers, from the
outset, to consider all elements of the product life cycle from concept through
disposal, including quality, cost, productivity, speed (time to market & response
time), and user requirements (include functional and reliability)."
Align all design to support the goal: Satisfy customer expectation
• Quality,
• Cost
• Productivity,
• Speed (time to market & response time)
• User requirements (include functional and reliability)
Support the goal: Return customer and Profitability- How serious?
•Sony battery recall lost $429 million combined 94% profit shrink
•Ford 3-rd net loss $5.8 billion close 16 plants, 45000 jobs
Concurrent Engineering:
Is a strategy where all the tasks involved in product development
are done in parallel.
Collaboration between all individuals, groups and departments
within a company.
• Customer research
• Designers
• Marketing
• Accounting
• Engineering
Concurrent Engineering
Concurrent Engineering
Form Design
Functional
Design
Production
Design
Revising and testing
prototypes
Manufacturing
Specifications
Design
Specifications
Feasibility
Study
Idea
Generation
Suppliers R&D Customers
MarketingCompetitors
Product or Service concept
Performance Specifications
Pilot run and final
tests
Final Design
and process
plans
Product Launch
Preliminary
Design
Commercial
Design Process
Linear Process
Concurrent Engineering
Demand for the proposed product?
Cost of developing and producing the product?
Does company have manufacturing capability?
Skilled personnel?
Concurrent Engineering
Form Design: Physical appearance of the product
Functional Design: Performance of the product
Production Design: How to manufacture product
Traditional Design and
Production Process
the main problems/difficulties associated with
traditional design and production process:
FOR COMPLEX PRODUCTS:
• Cycle Time Too Long
• Facility Intensive
• Cost High
• Convergence Not Assured
•Why do companies now want to move away from serial product
development process ?
Concurrent engineering of products
Address all issues related to the complete life cycle
of the product at the product design stage - from
initial conceptualization, to disposal/scrap of the
product.
Concurrent engineering
• Has to be supported by top management.
• All product development team members should be dedicated for
the application of this strategy.
• Each phase in product development has to be carefully planned
before actual application.
• New product’s lifecycle has to fit in in the existing product
program lifecycles in a company.
Benefits of Concurrent Engineering
•Reduces time from design concept to market launch by 25% or
more
• Reduces Capital investment by 20% or more
• Supports total quality from the start of production with earlier
•opportunities for continuous improvement
• Simplifies after-sales service
• Increases product life-cycle profitability throughout the supply
system
Assembly in the Context of Product
Development
Definition-various methods and forms of
design-importance of product design-static
and dynamic products-various design projects-
morphology of design-requirements of a good
design-concurrent engineering-computer
aided engineering-codes and standards-
product and process cycles-bench marking.
UNIT
1
COMPUTER-AIDED TECHNIQUES:
• CAD (computer-aided design)
• CAE (computer-aided engineering)
• CAM (computer-aided manufacturing)
• CAPP (computer-aided process planning)
• CAQ (computer-aided quality assurance)
• PPC (production planning and control)
• ERP (enterprise resource planning)
• A business system integrated by a common database.
Some or all of the following subsystems may be found in a
CIM operation:
WHAT IS CIM?
Basically Computer
Integrated Manufacturing
(CIM) is
the manufacturing approach of
using computers to control the
entire production process.
• In a CIM system functional areas such as design, analysis,
planning, purchasing, cost accounting, inventory control,
and distribution are linked through the computer with
factory floor functions such as materials handling and
management, providing direct control and monitoring of all
the operations.
As a method of manufacturing, three components distinguish CIM from
other manufacturing methodologies:
• Means for data storage, retrieval, manipulation and
presentation;
• Mechanisms for sensing state and modifying processes;
• Algorithms for uniting the data processing component with
the sensor/modification component.
• CIM is an example of the implementation
of information and communication technologies (ICTs)
in manufacturing.
• CIM implies that there are at least two computers
exchanging information, e.g. the controller of an arm
robot and a micro-controller of a CNC machine.
Some factors involved when considering a CIM
implementation are;
• The production volume,
• The experience of the company or personnel to make
the integration,
• The level of the integration into the product itself and
the integration of the production processes.
CIM is most useful where a high level of ICT is used in the company or facility,
such as CAD/CAM systems, the availability of process planning and its data.
KEY CHALLENGES:
INTEGRATION OF COMPONENTS FROM DIFFERENT SUPPLIERS:
• When different machines, such as CNC, conveyors and robots, are
using different communications protocols. In the case of AGVs, even
differing lengths of time for charging the batteries may cause
problems.
Data integrity:
• The higher the degree of automation, the more critical is the integrity
of the data used to control the machines.
• While the CIM system saves on labor of operating the machines, it
requires extra human labor in ensuring that there are proper
safeguards for the data signals that are used to control the machines.
Process control:
• Computers may be used to assist the human operators of the
manufacturing facility, but there must always be a competent
engineer on hand to handle circumstances which could not be
foreseen by the designers of the control software.
Definition-various methods and forms of
design-importance of product design-static
and dynamic products-various design projects-
morphology of design-requirements of a good
design-concurrent engineering-computer
aided engineering-codes and standards-
product and process cycles-bench marking.
UNIT
1
• Designing with codes and standards has two chief aspects:
(1) it makes the best practice available to everyone, thereby
ensuring efficiency and safety, and
(2) it promotes interchangeability
• A code is a collection of laws and rules that assists a government
agency in meeting its obligation to protect the general welfare by
preventing damage to property or injury or loss of life to persons
• A standard is a generally agreed-upon set of procedures, criteria,
dimensions, materials, or parts
• Engineering standards may describe the dimensions and sizes of
small parts like screws and bearings, the minimum properties of
materials, or an agreed-upon procedure to measure a property like
fracture toughness
• Codes tell the engineer what to do and when and under what
circumstances to do it.
• Standards tell the engineer how to do it and are usually
regarded as recommendations that do not have the force of
law
• There are two broad forms of codes: performance codes and
prescriptive codes.
• Performance codes are stated in terms of the specific
requirement that is expected to be achieved. The method to
achieve the result is not specified.
• Prescriptive or specification codes state the requirements in
terms of specific details and leave no discretion to the
designer.
• Design standards fall into three categories: performance, test
methods, and codes of practice.
• There are published performance standards for many products
such as seat belts and auto crash safety.
• Test method standards set forth methods for measuring properties
such as yield strength, thermal conductivity, or electrical resistivity.
• Most of these are developed for and published by the American
Society for Testing and Materials (ASTM). Another important set of
testing standards for products are developed by the Underwriters
Laboratories (UL)
• Codes of practice give detailed design methods for repetitive
technical problems such as the design of piping, heat exchangers,
and pressure vessels
• Many of these are developed by the American Society of
Mechanical Engineers (ASME Boiler and Pressure Vessel Code), the
American Nuclear Society, and the Society of Automotive Engineers
• The engineering design process is concerned with balancing
four goals: proper function, optimum performance,
adequate reliability, and low cost. The greatest cost saving
comes from reusing existing parts in design.
• Computer-aided design has much to offer in design
standardization. A 3-D model represents a complete
mathematical representation of a part that can be readily
modified with little design labor. It is a simple task to make
drawings of families of parts that are closely related.
• Group Technology (GT) GT is based on similarities in
geometrical shape and/or similarities in their manufacturing
processes.
• An important aspect of standardization in CAD-CAM is in
interfacing and communicating information between various
computer devices and manufacturing machines.
• The National Institute of Standards and Technology (NIST) has
been instrumental in developing and promulgating the Initial
Graphics Exchange Specification (IGES) code, and more recently
the Product Data Exchange Specification (PDES)
• Both of these standards represent a neutral data format for
transferring geometric data between equipment from different
vendors of CAD systems
Definition-various methods and forms of
design-importance of product design-static
and dynamic products-various design projects-
morphology of design-requirements of a good
design-concurrent engineering-computer
aided engineering-codes and standards-
product and process cycles-bench marking.
UNIT
1
Definition-various methods and forms of
design-importance of product design-static
and dynamic products-various design projects-
morphology of design-requirements of a good
design-concurrent engineering-computer
aided engineering-codes and standards-
product and process cycles-bench marking.
UNIT
1
What is Benchmarking
• A method for identifying and introduce best
practices in order to improve performance
• The process of learning, adapting, and measuring
outstanding practices and processes from any
organization to improve performance
Why Benchmark
• Identify opportunities to improve performance
• Learn from others’ experiences
• Set realistic but ambitious targets
• Uncover strengths in one’s own organization
• Better prioritize and allocate resources
When not to Benchmark
• Target is not critical to the core business functions
• Customer’s requirement is not clear
• Key stakeholders are not involved
• Inadequate resources to carry through
• No plan for implementing findings
• Fear of sharing information with other organizations
5 steps to successful benchmarking
The five key steps in the benchmarking process are:
Plan: Clearly establish what needs to be improved – make sure it is
important to you and your customers – and determine the data
collection methodology to be used.
Analysis: Gather the data and determine the current performance gap -
against a competitor, the industry or internally – and identify the
reasons for the difference.
Action: Develop and implement improvement plans & performance
targets.
Review: Monitor performance against the performance targets.
Repeat: Repeat the whole process – benchmarking needs to become
a habit if you are serious about improving your performance.
1. Planning
• Determine the purpose and scope of the project
• Select the process to be benchmarked
• Choose the team
• Define the scope
• Develop a flow chart for the process
• Establish process measures
• Identify benchmarking partners
2. Collecting Data
• Conduct background research to gain thorough
understanding on the process and partnering
organizations
• Use questionnaires to gather information
necessary for benchmarking
• Conduct site visits if additional information is
needed
• Conduct interviews if more detail information is
needed
3. Analysis
• Analyze quantitative data of partnering
organizations and your organization
• Analyze qualitative data of partnering
organizations and your organization
• Determine the performance gap
4. Improving Practices
• Report findings and brief management
• Develop an improvement implementation plan
• Implement process improvements
• Monitor performance measurements and track
progress
• Recalibrate the process as needed
Types of benchmarking
1. Competitor – comparing with leading organizations
with similar products or services and
adapting their approach.
2. Generic – comparisons of business process or
functions that are very similar, regardless of
industry.
3. Internal – a comparison of internal operations by
different departments within the same
organization.
4. Functional – comparisons to similar functions within
the same broad industry, or to industry
leaders.
5. Customer – the aim of the improvement program is
meeting and exceeding customer
expectations.
122
Advantages
• Learn from others experience & practices
• Allows examination of present processes
• Aids change & improvement
• Implementation / changes more likely
• Overall industry improvement
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Disadvantages
• What is best for someone else may not suit you
• Poorly defined benchmarks may lead to wasted
effort and meaningless results.
• Incorrect comparisons
• Reluctance to share information