1. Chapter 10 Managing Engineering Design

2. Advanced Organizer

3. Chapter Objectives
Describe the phases or stages in systems engineering and the new product development process
Recognize product liability and safety issues
Recognize the significance of reliability and other design factors

4. Nature of Engineering Design
Eng. Design Process
Information:
Statement of the problem
Design standards
Design methods
Information:
Drawings
Specifications
Financial estimates
Written reports
Oral presentations

5. Systems Engineering/ New Product Development
The design of a complex engineered system, from the realization of a need through production to engineering support in use is known as systems engineering (especially with military or space systems) or as new product development (with commercial systems).

6. New Product Development - Stages
Conceptual
Technical Feasibility or Concept Definition
Development
Commercial Validation
Production
Product Support
Disposal Stage

7. Systems Engineering Process (In each phase of development)
Requirements Analysis: Analyze customer needs, objectives, and constraints to determine the functional requirements.
Functional Analysis/Allocation Identify lower level functions needed to meet these functional requirements, and translate them into design requirements suitable as design criteria.
Synthesis. Define the system concept, configuration item alternatives and select the preferred set of product or process solutions to the level of detail required in the phase being conducted.

8. Systems Engineering Process (In each phase of development)
System Analysis and Control. Provide the progress measurement, assessment, and decision mechanisms required to evaluate design capabilities and document the design and decision data.
Trade-off (trade) studies
Risk management
Configuration management
Interface management
Systems engineering master schedule (SEMS)
Technical performance measurement (TPM)
Technical (design) reviews

9. Quality Function Deployment (QFD)
Quality function deployment is a team-based management tool in which the customer expectations are used to drive the product development process.
Conflicting characteristics or requirements are identified early in the QFD process and can be resolved before production.

10. Quality Function Deployment (QFD)
Key benefits:
product improvement,
increased customer satisfaction,
reduction in the total product development cycle, &
increased market share.

11. QFD: House of Quality Interrelationship between Technical Descriptors
How: Technical Descriptors
(Voice of the Organization)
What: Customer Reqmts
(Voice of Customer)
Relationship between
Requirements and Descriptors
Prioritized Customer Reqmts
Prioritized Technical Descriptors

12. 4 Phases of QFD Phase I: Product planning Phase II: Parts deployment
Phase III:
Process
planning
Phase IV:
Production
planning

13. Classical Model of QFD How What Matrix Voice of Customer
House of Quality
Tech. Performance Measures
Piece/Part Characteristics
Tech. Performance Measures
Subsystem Design Matrix
Process Parameters
Piece/Part Characteristics
Piece/Part Design Matrix
Production Operations
Process Parameters
Process Design Matrix

14. Portable Slide Projector
QFD Example:
Portable Slide Projector
Engineering Metrics
Brightness
Weight
Dimensions (girth + width)
Time/Tasks required to start
Distortion
Distance from presenter
Time to insert/pull-out slide
Attractive product
Customer Needs
Good image
Easy to transport
Keeps present. flowing
Image visible in bad conditions
Minimizes unplanned interruptions
Design makes the product attractive
Device sets up quickly
Works well for short present.

15. Portable Slide Projector—Phase I
QFD Example:
Portable Slide Projector—Phase I
Engineering Metrics
Brightness
Weight
Dimensions
Time/Tasks
Distortion
Distance
Time to insert/pull
Attractive product
Customer
Weights 9 1 3
Customer Requirements
Good image
Easy to transport
Device sets up quickly
Works well for short present.
Keeps present. flowing
Image visible in bad conditions
Minimizes unplanned interruptions
Design makes the product attractive 9 3 1
Raw
score
108
117
114 81 58 72 27
Relative
Weight
16%
17%
12% 8%
11% 4%

16. Portable Slide Projector—Phase II
QFD Example:
Portable Slide Projector—Phase II
Part Characteristics
Top case
Bottom
case
Lens
Condenser
Stand
Heat sink
Lamp
Relative
Phase I
Weights
16%
17%
13% 8%
10% 4%
Engineering Metrics
Brightness
Weight
Dimensions (girth + width)
Time/Tasks required to start pres.
Distortion
Distance from presenter
Time to insert/pull-out slide
Attractive product 9 1 3
Raw
score
3.6
3.3
4.4
4.9
1.1
1.3
2.7
Rel.
Weight
17%
15%
21%
23% 5% 6%
13%
Rank 3 4 2 1 7 6 5

17. Phases in Systems Engineering / New Product Development (DoD)
Pre-milestone zero studies
Concept exploration & definition
Demonstration and validation
Engineering and manufacturing development
Production and deployment
Operations and support

18. Phases in Systems Engineering / New Product Development (NASA)
Conceptual design studies
Concept definition
Design and development
Fabrication, integration, test, and certification
Pre-operations
Operations and disposal

19. Phases in Systems Engineering / New Product Development (NSPE/NIST )
Conceptual
Technical feasibility
Development
Commercial validation and production preparation
Full-scale production
Product support

20. Tasks Within Each Phases of Systems Eng. / New Product Development
Approval to expend the resources / agreement on the work to be accomplished.
Accomplishment of the work
Compile the results: designs and specifications, analyses and reports, and a proposed plan for conducting the following phase if one is recommended.
To cancel the development,
To go back (recycle) and do more work in the present phase; or
To proceed with the next phase.

21. Conceptual stage
Statement of the design problem, clearly defining what the desired intended accomplishment of the desired product
Key functions
Performance characteristics
Constraints
Criteria of judging the design quality

22. Conceptual stage Musts: requirements that must be met
Must nots: constraints defining what the system must not be or do
Wants: features that would significantly enhance the value of the solution but are not mandatory (to which an additional, even less compelling category of "nice to have" is often added)
Don't wants: characteristics that reduce the value of the solution

23. Conceptual stage (Kano’s Model)
Customer Satisfaction
Delighters
Satisfiers
Actual Performance
Dissatisfiers

24. Conceptual stage (Kano’s Model)
Dissatisfiers
Expected Quality
Scratches, blemishes
Smooth Surface
Broken parts
All parts work
Missing instruction
Clear instruction
Function not provided
Normal function
Product is unsafe
Product is safe to use
Product is non-conformant
Product conforms to std.

25. Conceptual stage (Kano’s Model)
Satisfiers:
Direction
Performance Measure
Desired Quality
LargerTB
Cubic feet of storage
Capacity
SmallerTB
Dollars
Price
LargerTB
MTBF
Reliability
LargerTB
Transactions /second
Speed

26. Conceptual stage (Kano’s Model)
Examples of Delighters
Sony Walkman
3M Post-it
Cup Holder
One-touch recording
Redial button on telephone
Graphic User Interface (GUI)

27. Results from Conceptual stage
A set of functional requirements
Identification of the potential barriers to development, manufacturing, and marketing the proposed product.
Test-of-principle model to reduce technical uncertainties
Order-of-magnitude economic analyses and
Preliminary market surveys to reduce financial uncertainty.

28. Importance of Conceptual stage
1% of the cost of the product
70 % of the life-cycle cost

29. Technical feasibility stage
The objectives of this stage are
To confirm the target performance of the new product through experimentation and/or accepted engineering analysis and
To ascertain that there are no technical or economic barriers to implementation

30. Technical feasibility stage
Subsystem identification
Trade-off studies
System integration
Interface definition
Preliminary breadboard-level testing
Subsystem and system design requirements (reliability, safety, maintainability, and environmental impact).
Development of preliminary test plans, production methods, maintenance and logistic concepts, and marketing plans.
Preliminary estimation of the life-cycle cost of the system.
Preparation of a proposal for the development stage

31. Importance of Technical feasibility stage
7% of the cost of the product
85 % of the life-cycle cost

32. Development stage (Build-test-fix-retest sequences)
The objective of this stage is
To make the needed improvements in materials, designs and processes and
To confirm that the product will perform as specified by constructing and testing engineering prototypes or pilot processes.

33. Commercial validation and Production preparation stage
The objective of this stage is to develop the manufacturing techniques and establish test market validity of the new product.
Selecting manufacturing procedures, production tools and technology, installation and start-up plans for the manufacturing process, and
Selecting vendors for purchased materials, components, and subsystems.
 Reproduction prototypes

34. Full-scale production stage
Final design drawings, specifications, flow charts, and procedures are completed for manufacture and assembly of all components and subsystems of the product, as well as for the production facility.
Quality control procedures and reliability standards are established
Contracts made with suppliers
Procedures established for product distribution and support.
Manufacturing facilities are constructed
Continuous process improvement (kaizen)

35. Product support stage
Technical manuals for product installation, operation, and maintenance
Training programs for customer personnel
Technical supports
Warranty services
Repair parts and replacement consumables must be manufactured and distributed
New procedures for operation and maintenance
Improved parts for retrofit
Notification of product recall for safety reasons

36. Disposal stage
Every product causes waste during manufacture, while in use, and at the end of useful life that can create disposal problems.
The time to begin asking, "how do we get rid of this" is in the early stages of product or process design.

37. CONCURRENT ENGINEERING AND CALS

38. Traditional Product Development
System Level Design
Subsystem Design
Component Design
Manufacturing Process Concept Development
Manufacturing Process Development
Delivery Development
Service Development
Delivery

39. Concurrent Processes System Level Design
Manufacturing Process Concept Development
Delivery Development
Subsystem Design
Manufacturing Process Development
Service Development
Component Design
Production & Delivery

40. Definition of Concurrent Engineering
A systematic approach to the integrated, concurrent design of products and their related processes, including manufacture and support.
This approach is intended to cause the developer, from the outset, to consider all elements of the product lifecycle from concept through disposal, including quality control, cost, scheduling, user requirements. (Inst. For Defense Analysis)

41. Advantages of Concurrent Engineering
The set of methods, techniques, and practices that:
Cause significant consideration within the design phases of factors from later in the life cycle;
Produce, along with the product design, the design of processes to be employed later in the life of the product;
Facilitate the reduction of the time required to translate the design into distributed products; and
Enhance the ability of products to satisfy users' expectations and needs.

42. CALS "Computer Aided Logistics Support," then
"Computer-aided Acquisition and Logistics Support,"
"Continuous Acquisition and Life-Cycle Support," (1993, DoD)
"Commerce At Light Speed" (U.S. industry)

43. Purposes of CALS
To enable more effective generation, management, and use of digital data supporting the life cycle of a product through the use of international standards, business process change, and advanced technology application.

44. CALS Electronic storage, transmission, and retrieval of digital data
Between engineers representing the several design stages,
Between organization functions such as marketing, design, manufacturing, and product support, and
Between cooperating organizations such as customer and supplier.

45. Commercial standards
Computer Graphics Metafile (CGM) (ISO-8632): A standard means of representing line drawings in a device-independent way.
Electronic Data Interchange for Administration, Commerce, and Transport (EDIFACT) (ISO 9735, ANSI X12): An international standard means for communicating commercial (trade) information.
Initial Graphics Exchange Specification (IGES) (ANSI Y14.26M): A standard means of representing product data in a device-independent way.

46. Control Systems in Design
Drawing/Design Release
Version Control
Product Data Management (PDM)
Configuration (Design Criteria) Management
Functional baseline (at end of conceptual stage)
Allocated baseline (at end of validation stage)
Product baseline (at end of development stage)
Design Review

47. Special Considerations in Design
Product liability
Safety
Reliability
Maintainability
Availability
Ergonomics
Producibility

48. History of Product Liability
Caveat emptor (let the buyer beware)
“Privity of contract” (Direct contractual relationship)
1916, MacPherson v. Buick (No need for direct contract)
Plaintiff must prove negligence
1960, Hernington v. Bloomfield Motors,  implied warranty
1984, Greenman v. Yuba Power Product Strict Liability
Absolute liability: “A manufacturer could be held strictly liable for failure to warn of a product hazard, even if the hazard was scientifically unknowable at the time of the manufacture and sale of the product.”

49. Reducing Liability
Include safety as a primary specification for product design.
Use standard, proven materials and components.
Subject the design to thorough analysis and testing.
Employ a formal design review process in which safety is emphasized.
Specify proven manufacturing methods.
Assure an effective, independent quality control and inspection process.
Be sure that there are warning labels on the product where necessary.

50. Reducing Liability
Supply clear and unambiguous instructions for installation and use.
Establish a traceable system of distribution, with warranty cards, against the possibility of product recall.
Institute an effective failure reporting and analysis system, with timely redesign and retrofit as appropriate.
Document all product safety precautions, actions, and decisions through the product life cycle.

51. Designing for Reliability
Definition of Reliability:
Reliability is the probability that a system
Will demonstrate specified performance
For a stated period of time
When operated under specified conditions.

52. Reliability Measures Reliability
Failure CDF (cumulative distribution function):
Failure PDF (probability density function):
Failure or hazard rate:

53. Simple Reliability Models
Simple Series Model S L
Simple Parallel Model L

54. Simple Reliability Models
Series- parallel model L S L S

55. Simple Reliability Models Bathtub curve
Hazard
Rate
Life
Infant
Mortality
Useful Life
Wear-out

56. Designing for Reliability
“Start with the best”
Redundancy
Factor of safety

57. Maintainability
Maintainability is the probability that a failed system
Will be restored to specified performance
Within a stated period of time
When maintained under specified conditions.

58. Maintainability Maintenance downtime Administrative & preparation time
Logistic time
Active maintenance time
Types of Maintenance
Corrective maintenance
Preventive maintenance
Predictive maintenance

59. Availability
Inherent Availability (considers only corrective maintenance)
Ai = MTBF / (MTBF+MTTR)
Operational Availability (considers both preventive & corrective maintenance)
Ao = MTBM / (MTBM+MDT)
MTBM: Mean Time Between Maintenance
MDT: Mean Down Time
MTTR: Mean Time To Repair
MTBF: Mean Time Between Failure (1/)
BIT: Build-In Test

60. Other Considerations Human Factors Engineering (Ergonomics)
Standardization
Set of specifications for parts, materials, or processes intended to achieve uniformity, efficiency, and a specified quality.
Producibility

61. Value Engineering
A methodical study of all components of a product in order to discover and eliminate unnecessary costs over the product life cycle without interfering with the effectiveness of the product.
What is it?
What does it do?
What does it cost?
What does it worth?
What else might do the job?
What do the alternatives cost?
Which alternative is least expensive?
Will the alternative meet the requirements?
What is needed to implement the alternative?