Biomechanical Design (051:083)

1. Biomechanical Design(051:083) • Lecturer: • - Tae-Hong Lim, Ph.D. • 1420 Seamans Center • 335-5810 (office); talim@engineering.uiowa.edu (email) • - David Wilder, PhD and Nicole Grossland, PhD • Office Hours: • M, W, F: 4:00 – 5:00 PM • Appointment • Pre-requisites: • 57:007 Statics • 57:019 Mechanics of Deformable Bodies • 51:050 Biomechanics

2. Text and Grading • Text: “The Mechanical Design Process, 3rd Edition” David G. Ullman McGraw-Hill (ISBN: 0-07-237338-5) • Grading: 15% Homework and Quiz 20% Individual Design Notebook 10% Reverse engineering report 40% Team Project 15% Final Exam • Final exam will be a short answer exam covering the terminology and concepts studied throughout this course

3. Individual Design Notebooks • You are to keep a design notebook for use in this course. • This is to be a spiral bound notebook. • Every page must be numbered at the beginning of the term. • No pages can be removed and each page must be dated and initialed when used. • All work related to this course (homework and design project) will be entered into this note book. • Each notebook will be collected at the end of the term and graded on the number of “quality entries” it contains. • A quality entry is a significant sketch or drawing of some aspect of design; a listing of functions, ideas or other features; a table such as morphology or decision matrix; or a page of text. • Unintelligible entries are not quality entries.

4. Team Project • Design Team: • Design teams will be organized by the instructor. • Team members will determine the leader (CEO). • Team Project: • Each team will determine a design problem (new invention or modification) related to biomechanical devices through discussion with the instructor. • The team project will be considered completed by obtaining final product documentation (drawings, part list with specified materials, and assembly instructions). • No final product in physical form is required. • Each team should record the whole history of the design in the Product Development File (PDF).

5. Documents in the PDF • Problem Appraisal Phase • Understanding the Problem: • Description of Customers • Customer’s Requirements • Weighting of Customer’s Requirements • Competition’s Benchmarks vs. Customer’s Requirements • Engineering Requirements • Competition’s Benchmarks vs. Engineering Requirements • Engineering Targets • Planning the Project • Task Titles • Objectives of Each Task • Personnel Required for Each Task • Time Required for Each Task • Schedule of Tasks • Conceptual Design Phase • Concept Generation: • Function Decomposition • Literature and Patent Search Process and Results • Function-Concept Mapping • Sketches of Overall Concepts • Concept Evaluation and • Assessment of Tech. Readiness: • Identification of Failure Modes • Identification of Critical Parameters • Concept Selection: • Decision Matrices to Determine Best Concepts • Analsysi, Experiments and Models Supporting Evaluation • Product Design Phase • Product Generation: • Usable off-the-shelf Products • Shape Development Driven by Function • Materials Selection • Manufacturing Process Selection • Product Evaluation: • Comparison to Engineering Function • Functional Changes Noted • Design for Assembly Evaluation • Cost Evaluation • Analysis, Experiments and Models Supporting Evaluation • Final Product Documentation: • Layout Drawings • Detail Drawings of Manufactured Parts • Parts List (Bill of Materials) • Assembly Instructions * The file is to be maintained by the group in a binder. This PDF, when completed, is effectively a final report. It will be graded on completeness and quality of both the design and the documentation itself.

6. Biomechanical Design • Design: • Deliberate purposive planning • A mental project or scheme in which means to an end are laid out • A preliminary sketch or outline showing the main features of something to be executed: DELINEATION • The arrangement of elements or details in a product or work of art • The creative art of executing aesthetic or functional designs • Biomechanical Design: • Design something related to biomechanics, such as: Biomechanical devices • Medical devices: orthopedic implants, scissors, scalpers, staplers, etc. • Exercising devices: treadmill, weight-lifting, helmets, wrist-guards, etc. • Rehabilitation devices: wheel-chairs, canes, etc. Biomechanical activities • Exercises for fitness or strengthening body parts • Biomechanical design includes: • Development (or invention) of new biomechanical stuffs; and • Modification of existing biomechanical stuffs

7. What will we learn in this class? • Typical design process: • Identification of design problems • Design • Evaluation of the design • Decision making • Final report • Techniques helping generate better quality designs in less time: • Concurrent engineering • Computer aided drawing • Legal and regulation issues: • Safety and liability • Patent, FDA, CE, and UL • Importance of communication of design data: • Records of design data, design process, and final report • Oral presentations

8. The Life of A Product *Process of idea development, production, use, and end of product life. *The whole process must be considered in the design process.

9. Design Process • What is the design process? • Design process is the organization and management of people and the information they develop in the evolution of the product. • Why study the design process? • Design process determines the efficiency of new product development. • 85% of the problems with new products not working as intended, taking too long to bring to market, or costing too much are the result of poor design process. • The design process needs to improved consistently and executed for developing better products because: • There is a continuous need for new, cost-effective, high-quality products. • Most products require a team of people from diverse areas of expertise to develop an idea into hardware. • We will study the design process to get the tools to develop an efficient design process regardless of the product being developed. • 3 types of knowledge used by designers: • Knowledge to generate ideas • Experience and natural ability • Knowledge to evaluate ideas • Experience and formal training (focus of most engineering education) • Knowledge to structure the process • Non-domain-specific knowledge • What we will study in this class

10. History of the Design Process • One person, with sufficient knowledge of the physics, materials and manufacturing processes to manage all aspects of the design and construction of the project, could design and manufacture an entire product in the past. • By the middle of the 20th century, products and manufacturing processes had become too complex for one person to have sufficient knowledge or time to focus on all aspects of the evolving product. • Different groups of people for marketing, design, manufacturing and overall management • One-way communication over the wall: • What is manufactured is not often what the customer had in mind. • Inefficient, costly, and greater possibility for making poor-quality products

11. History of the Design Process • Simultaneous Engineering (in late 1970s and early 1980s): • Simultaneous development of the manufacturing process with the evolution of the product by assigning manufacturing representatives to be members of design team • Concurrent Engineering (in late 1980s): • Integrated Product and Process Design (IPPD) in the 1990s • A greater refinement in thought about what it takes to efficiently develop a product • Primarily focusing on the integration of teams of people, design tools and techniques, and information about the product and the processes used to develop and manufacture it. • 10 Key Features of Concurrent Engineering • Focus on the entire product life (chap 1) • Use and support of design team (chaps 3 and 5) • Realization that the processes are as important as the product (chaps 4 and 5) • Attention to planning for information-centered tasks (chap 5) • Careful product requirements development (chap 6) • Encouragement of multiple concept generation and evaluation (chaps 7 and 8) • Awareness of the decision-making process (chap 8) • Attention to designing in quality during every phase of the design process (throughout) • Concurrent development of product and manufacturing process (chaps 9-13) • Emphasis on communication of the right information to the right people at the right time (throughout) • A key point of concurrent engineering is a concern for information. • Drawings, plans, concept sketches, meeting notes, etc.

12. Controllable Variables in Concurrent Engineering

13. Overview of the Design Process

14. Design Problems • Design a joint to fasten together two pieces of 1045 sheet steel (4 mm thick and 6 cm wide), which are lapped over each other and loaded with 100 N? • Ill-defined design problem with number of potential problems • How to connect the sheets? (Bolted, glued, welded, etc.?) • Disassembly required later? • What working environment? • etc. What size SAE grade 5 bolt should be used to fasten together two pieces of 1045 sheet steel (4 mm thick and 6 cm wide) which are lapped over each other and loaded with 100 N? - Well defined analysis problem finding the diameter of the bolt HWK#1: Change a problem from one of your engineering science classes into a design problem by changing as few words as possible. Do your home work in your design notebook. Due is one week.

15. Design problems have many satisfactory solutions and no clear best solution. • Design problems • are ill-defined; • have no correct answer; • have no clear best answer. • Design process knowledge is based upon the domain knowledge. Mechanical design problems begin with an ill-defined need and result in a piece of machinery that behaves in a certain way. PARADOX: A designer must develop a machine that has the capabilities to meet some need that is not fully defined.

16. Basic Actions of Design Problem Solving • ESTABLISH the need or realize that there is a problem to be solved. • New needs also can be established throughout the design effort because new design problems arise as the product evolves. Design of these details poses new subproblems. • PLAN how to solve the problem. • Planning occurs mainly at the beginning of a project. Plans are always updated because understanding is improved as the process progresses. • UNDERSTAND the problem by developing requirements and uncovering existing solutions for similar problems. • Formal efforts to understand new design problems continue throughout the process. Each new subproblem requires new understanding. • GENERATE alternative solutions. • Concept Generation vs. Product Generation • EVALUATE the alternatives by comparing them to the design requirements and to each other. • Evaluation techniques also depend on the design phase; there are differences between the evaluation techniques used for concepts and those used for products. • DECIDE and acceptable solutions • Decision making requires a commitment based upon incomplete evaluation. • Decision requires a consensus of team members. • COMMUNICATE the results • Communication of the information developed to others on the design team and to management is an essential part of concurrent design.

17. Basic Terminologies used to describe the Design Process • “Communication” as a one key feature of concurrent engineering • Communication depends on a shared understanding of terminology. • Function: • What a product or a system is supposed to do; • Described using action verbs and a noun describing the object on which the action occurs: • Record images; quantify the blood pressure; fix an unstable spine segment; etc. • System: • A grouping of objects that perform a specific function; • Shutter system; timer system; CD-R system; cooling system; etc. • A system can be decomposed into another subsystems or further into individual components (or parts). • Multiple systems can be assembled into a higher level system or further into a final product. • Feature: the important form and function aspects of mechanical devices • dimensions, material properties, shapes, or functional details (speed of opening and closing for shutter system) In general, during the design process, the function of the system and its decomposition are considered first. After the function has been decomposed to the finest subsystems possible, assemblies and components are developed to provide these functions. Decomposition of design disciplines

18. Function, Behavior, and Performance • Function: • describes what a device does. • But, function provides no information about how a device accomplishes the function. • Form: • The term “form” relates to any aspect of physical shape, geometry, construction, material, or size. • provides some information on how a device accomplishes the function. • Behavior and Performance in association with Function. • Function is the desired output from a system yet to be designed. • Behavior is the actual output, the response of the system’s physical properties to the input energy or control. • Performance is the measure of function and behavior – how well the device does what it is designed to do. • A clear picture of desired performance should developed in the beginning of the design process.

19. Types of Mechanical Design Problems • Selection Design: • choosing one item (or more) from a list of similar items • choosing a bearing, bolt, motor, etc. from a catalog • Configuration Design: • How to assemble all the components into the completed product • Parametric Design: • Finding values for the features that characterize the object being studied or that meet the requirements • Design a cylindrical tank: V = r2l, determine r and l for known V • Original Design: • Design a process, assembly or component not previously in existence • Redesign: • Redesign of an existing product • Most design problems are redesign problems since they are based on prior, similar solutions. Conversely, most design problems are original as they contain something new that makes prior solutions inadequate.

20. Languages of Mechanical Design A mechanical object can be described by: • Semantic language: • Verbal or textual representation of the object • “bolt” or “The shear stress is equal to the shear forces on the bolt divided by the x-sectional area.” • Graphical language: • drawing of the object • Sketches, scaled representations of orthogonal drawings, or artistic renderings • Analytical Language: • Equation, rules, or procedures representing the form of function of the object •  = F/A • Physical Language: • Hardware or physical model of the project - In most cases, the initial need is expressed in a semantic language as a written specification or a verbal request by a customer or supervisor, and the final result of the design process is a physical product.

21. Design, State, Constraints and Decision • Design State: • Collection of all the knowledge, drawings, models, analyses and notes thus far generated • In the beginning, design state is just the problem statement • Design Constraints: • Factors limiting the design process • Examples: size, strength of material, corrosion properties, anatomy, etc. • In the beginning, the design requirements effectively constrains the possible solutions to a subset of all possible product designs. • Two sources of constraints added during the design process: • Designer’s knowledge of mechanical devices and the specific problem being solved • Result of design decisions • Design Decision: • Continuous comparison between design state and the goal (requirements for the product given in the problem statement) • The difference controls the process. • Design is the successive development and application of constraints until only one unique products remains. • Each design decision changes the design state. • The design progresses in increment punctuated by design decisions.

22. The Value of Information *The most valuable information is the decisions that are communicated to others.

23. Design as Refinement of Abstract Representations See Table 2.2 for levels of abstraction in other languages. Graphical Refinement

24. Information-processing Model of Human Problem Solving Information-Processing System used by the human mental system in solving any type of problem

25. Chunks of Information

26. Information-processing Model of Human Problem Solving Types of Knowledge that might be in a chunk of information: • General knowledge • Information that most people know and apply without regard to a specific domain • “red is a color.” “4 is bigger than 3.” • Gained through everyday experiences and basic schooling • Domain Specific Knowledge: • Information on the form or function of an individual object or a class of objects • Bolts are used to carry shear or axial stress • The proof stress of a grade 5 bolt is 85 kpsi. • Gained from study and experience in the specific domain • It may take about 10 years to gain enough specific knowledge to be considered an expert in a domain • Procedural Knowledge: • The knowledge of what to do next • If there is no answer to problem X, then decompose X into two independent subproblems of x1 and x2 that are easier to solve. • Gained mostly from experience • Required for solving mechanical design problems

27. Implications of the Information-processing Model • The size of STM is a major limiting factor in the ability to solve problem. • To accommodate this limitation, breakdown problems into finer and finer subproblems until we can “get our mind around it” • in other word, manage the info in our STM • Human designers are quite limited although our expertise about the constraints and potential solutions increases and our configuration of chunks becomes more efficient as we solve problems. • These limitations would preclude our ability to solve complex problems.

28. Mental Processes that Occur during Design • Understanding the problem: • A problem is understood by comparing the requirements on the desired function to information in the long-term memory. • Every designer’s understanding of the problem is different, we need to develop a method to ensure that the problem is fully understood with minimal bias from the designer’s own knowledge. • Generating a solution: • Use the information stored in LTM that meets the design requirements. • If no solution found from LTM, then use a three step approach • Decompose the problem into subproblems • Try to find partial solutions to the subproblems • Recombine the subsolutions to fashio a total solution • Creative part of this approach is in knowing how to decompose and recombine cognitive chunks • Evaluating the solution: • Evaluation requires comparison between generated ideas and the laws of nature, the capability of technology and the requirements of the design problem itself. • Evaluation requires modeling the concept to see how it performs. • The ability to model is usually a function of knowledge in the domain. • Deciding: • A decision is made at the end of each problem-solving activity to accept the generated and evaluated idea or to address another topic that is related to the problem. • Controlling the design process: • Path from initial problem to solution seemed random.

29. Problem-Solving Behavior • A person’s problem-solving behavior affects how problems are solved individually and has a significant impact on team effectiveness. • Four Personal-Problem Solving Dimensions (or styles): • Individual Problem-solving Style: • Introvert: • Solve problem internally (reflective); a good listener; think and speak; enjoy having time alone for problem solving • Extrovert: • Sociable; tend to speak and think • About 75% Americans and 48% of engineering students and executives • Individual Preference to work with Facts or Possibilities: • Facts oriented people: • literal, practical, and realistic • 75 % of Americans, 66% of top executives, 34% of all engineering students • Possibility oriented people: • Like concepts and theories and look for relationship between pieces of information and meaning of the information • Objectivity with which decisions are made: • Objective: • Logical, detached and analytical • Taking objective approach to make decisions • 51% of Americans, 68% of engineering students, 95% of top executives • Subjective: • Make decisions based on an interpersonal involvement, circumstances, and the “right thing to do” • Need to Make Decisions: • Decisive: • Tend to make decisions with a minimum of stress and like an ordered, scheduled, controlled and deliberate environment • 50% of Americans, 64 % of engineering students, and 88% of top executives • Flexible: • People goes with flow is flexible, adaptive, and spontaneous, and finds making and sticking with decisions difficult • Please make sure to read section 3.3.6 carefully for better design team activities.

30. Characteristics of a Creative Designer • Problem solving involves: • Understanding the problem, generating solutions, evaluating the solutions, deciding on the best one, and determining what to do next • Criteria of Creative Solution: • It must solve the design problem. • It must be original. • Originality and creativity are assessed by society. • Creativity in relation to other Attributes • Intelligence: no correlation with creativity • Visualization Ability: • Creative engineers have good ability to visualize, to generate and manipulate visual images in their head. • The ability to manipulate complex images can be improved with practice and experience. • Knowledge: • A person must have knowledge of existing products to be a creative designer • A firm foundation in bioengineering science is essential to being a creative biomechanical designer. • Partial Solution Manipulation: important attribute • Risk Taking: certainly required • Conformity: Creative people tend to be nonconformists. • Constructive nonconformists take a stand because they think they are right and might generate a good idea. • Obstructive nonconformists take a stand just to have an opposing view and will slow down the design progress. • Technique: • Creative designers have more than one approach to problem solving. • Environment: • Higher creativity when the work environment allows risk taking and nonconformity and encourages new ideas. • Practice: • Creativity comes with practice. • Practice enhances the number and quality of ideas.

31. Creative Designer • A creative designer is a: • Visualizer; • Hard worker; and • Constructive nonconformist with knowledge about the domain and ability to dissect things in his or her head • Good News: • Designers with no strong natural ability can develop creative methods by using good problem-solving techniques to help decompose the problems in ways that maximize the potential for understanding it, for generating good solutions, for evaluating the solutions, for deciding which solution is best and for deciding what to do next • A design project requires: • much attention to detail and convention; • demands strong analytical skills; and thus • People with a variety of skills. • There are many good designers who are not particularly creative individuals.

32. Engineering Design Team • A team is a group of people working toward a common understanding. • Team vs. Individual Problem Solving • There are social aspects of team work. • Each team member may have different understanding of the problem, different alternatives for solving it, and different knowledge for evaluating it. (more solutions but also more confusion) • Team Goals: • A small number of people with complementary skills who are committed to a common purpose, common performance goals and a common approach for which team members hold themselves mutually accountable are required for an effective team. • Team members must: • learn how to collaborate with each other, i.e., to get the most out of other team members. • Comprise to reach decisions through consensus rather than by authority. • Establish communications. • Be committed to the good of the team. • Team Roles: • Organizer; Creator; Resource-investigator; Motivator; Evaluator; Team worker; Solver; Completer (finisher or pusher) • Building Team Performance: • For developing productive teams; • Keep the team productive • Select team members on the basis of skills in both primary and secondary roles • Establish clear rule of behavior • Set and seize upon a few immediate performance-oriented goals. • Spend time together. • Develop a common understanding

33. Overview of the Design Process An Ideal Flow Chart of Activities During Design Process

34. What initiates a Design Project? • Need for a New Design: • Market: • About 80% of new product development is market-driven. • Assessment of the market is most important in understanding the design problem because there is no way recover the costs of design and manufacture without market demand. • Incorporation of the latest technology can improve its perception as a high quality product. • New product idea without market demand • To use new technologies whose development requires an extensive amount of capital investment and possibly years of scientific and engineering time • High financial risk but greater profit due to uniqueness • Examples of successful products: sticky notes; Walkman • Need for Redesign • By market demand for a new model • Desire to include a new technology • Fix a problem with an existing product • Redesign process can be applied to the subproblems that result from the decomposition of a higher-level system.

35. Overview of the Design Process • Project Planning: • to allocate the resources of money, people, and equipment to accomplish the design activities: • Planning should precede any commitment of resources although requiring speculations about the unknowns • Easier to plan a project similar to earlier projects than to plan a totally new one • Plans are often updated whenever unknown demands become certain with the progress of design project • Specifications Definition: • Goal is to understand the problem and to lay the foundation for the remainder of the design project. • Identify the customers: Generate the customer’s requirements: Evaluate the competition: Generate engineering specifications: Set targets for its performance • Design Review: • formal meeting for progress report and design-decision making • Conceptual Design: • To generate and evaluate the concepts for the product • Generate concepts based on the defined specifications for developing a functional model of the product • Evaluate concepts by comparing the concepts generated to the targets for its performance • Design Review • Product Development: • Evaluate the product for performance, cost, and production • Make product decisions • Documentation and Communication • BOM (Bill of Materials), Drawings, etc. • Product Support: • Support for vendors, maintenance of engineering change, customer, manufacturing and assembly, and retirement of the product

36. Why Do We Have to Follow The Design Process Techniques? • Paradox: • Techniques in the design process may imply “RIGIDITY” whereas the creativity implies “FREEDOM.” • Following the techniques in the design process helps the designers develop a quality product that meets the needs of the customer by several ways: • Eliminating expensive changes later • Developing creative solutions to design problems systematically • Creativity does not spring from randomness. • “Genius is 1 percent inspiration and 99 percent perspiration.” • The inspiration for creativity can only occur if the perspiration occur early is properly directed and focused. • The techniques that make up the the design process are only an attempt to organize the perspiration. • Forcing documentation of the progress of the design (record of the design’s evolution) that will be useful later in the design process.

37. Design Process Examples Simple Process Complex Process

38. Communication during the Design Process • Design Records: • Importance of documents in design file: • To demonstrate the state-of-the-art design practices • To prove originality in case of patent application • To demonstrate professional design procedures in case of a lawsuit • Design Notebook: • A diary of the design tracking the ideas development and the decision made in a design notebook • Name; Affiliation; Title of the problem; Problem Statement; and all sketches, notes and calculations that concerns the design • A design notebook sequentially numbered, signed and dated pages is considered good documentation whereas random bits of information scrawled on bits of papers are not. • Good evidences for legal purposes (patent or lawsuit) as well as a reference to the history of the designer’s own work • Documents Communicating with Management: • Needed for periodic presentations to managers, customers, and other team members for design review • Regardless of its form (oral or written); • Make it understandable (consider the recipients’ level of knowledge about the design problem) • Carefully consider the order of presentation (whole – parts – whole: 3-step approach: gradual introduction of new ideas) • Be prepared with quality material (good visual and written documentation; following the agenda; being ready for questions) • Documents Communicating the Final Design: • Material describing the final design, e.g, Drawings (or data files) of individual components and of assemblies • Written documentation to guide • manufacture, assembly, inspection, installation, maintenance, recruitment, and quality control

39. Team Project • Select an original design problem to solve throughout the remainder of the course. • The problem should concern biomechanical devices in which some of the design team members have some knowledge or training. • The final product will be data from analyses and evaluation and final drawings, not an actual hardware. • Design Team Activity : • Each student should start gathering the design ideas immediately and recording the ideas in the design notebook. • Start the team meeting ASAP for: • Organization of the team • Planning the design process to finish the project by the end of April. • Each team will present their design project in May. Any discussion about the design project with the instructor is welcome.

40. Project Definition and Planning • Concurrent engineering encourages involvement through out the entire product life cycle from the project definition to product retirement. • Project definition and planning is the first phase of the mechanical design process.

41. Project Definition • Why developing new products? • To fill some market need • Mostly driven by the customer • To exploit a technological development • Driven by new technologies and what is learned during the design • Project Definition: • the challenges of choosing from the many suggestions as to which products to spend time and money on to develop or refine • “Fuzzy front end” of dealing with vague design ideas • Specific Questions in Project Definition Phase: • Is there a good potential return on investment (ROI)? • Does the new product or improvement fit the company image? • Does it fit the distribution channels? • Is there sufficient production capacity in-house or with known vendors? • What will the project cost?

42. Project Planning • Planning is like trying to measure the smile of the Cheshire cat; you are trying to quantify something that isn’t there. • Planning is the process used to develop a scheme for scheduling and committing the resources of time, money, and people. • Producing a map showing how product design process activities are scheduled. • The whole activities of specification definition, conceptual design, and product development must be scheduled and have resources committed to them • Planning generates a procedure for developing needed information and distributing it to the correct people at the correct time. • Important information: product requirements, concept sketches, system functional diagrams, component drawings, assembly drawings, material selections, and any other representation of decisions made during the development of the product. • Typical Master Plan (a generic process) of a Company for Specific Products: • A blue print for a process: • product development process; delivery process; new product development plan; or product realization plan, etc. • We will refer to this generic process as the product development process (PDP).

43. ISO-9000 • A quality management system of the International Standard Organization • First issued in 1987 and now adopted by over 150 countries • Over 350,000 companies worldwide and 8500 U.S. companies have the ISO-9000 certification • ISO-9000 registration means that the company has a quality system that: • Standardizes, organizes, and controls operations. • Provides for consistent dissemination of information. • Improves various aspects of the business-based use of statistical data and analysis. • Enhances customer responsiveness to products and services. • Encourage improvement. • To receive certification, • One should develop a process that describes how to develop products, handle product problems, and interact with customers and vendors. • Required written procedures that: • Describe how most work in the organization gets carried out (i.g., the design of new products, the manufacture of products, and the retirement of products). • Control distribution and reissue of documents. • Design and implement a corrective and protective action system to prevent problems from recurring. • Evaluation of the effectiveness of the process by an accreditted external auditor • Certification expires in 3 years and audits at 6-month intervals to maintain the currency of the certificate. • ISO-9000 requires a company to have a documented development process on which the plan for a particular product can be based.

44. Background for Developing a Design Project Plan • A plan tells how a project will be initiated, organized, coordinated, and monitored, e.g., managerial activities. • Types of Design Projects: • Variation of existing product: • Improvement of existing product: • Redesign of some features of an existing product due to: • Customers request; no longer supply of materials or components from the vendor; needed improvement in manufacturing; or New technology or new understanding of an existing technology • Development of a new product for a single (or small) run or for mass production • Members of the Design Team: • Product design engineer: • Product manager (product marketing engineer): • Manufacturing engineer; Detailer; Drafter; Technician; Materials specialist; QC/QA specialist; Analyst; Industrial engineer; Assembly manager; Vendor’s or supplier’s representatives • Structure of Design Teams: • Functional Organization (13 %): • Each project is assigned to a relevant functional area, focusing a single discipline • Functional Matrix (26 %): • project manager with limited authority is designated to coordinate the project across different functional areas • Balanced Matrix (16 %): • A project manager is assigned to oversee the project and shares the responsibility and authority with functional managers. • Project Matrix (28 %): • A project manager oversees the whole project and functional managers assign personnel as needed. • Project Team (16 %) • Organize the talent around the project whenever possible. • Structures focus on the project are more successful than those built around the functional areas in the company.

45. Planning for Deliverables • Deliverables: • All models of the product, such as drawings, prototypes, bills of materials, analysis results, test results, and other representations of the information generated in the project • Measure of the progress in design project • Models vs. Prototypes: • Models are analytical and/or physical representations of design information. • Prototypes are physical models. Solid models in CAD can replace the physical models these days. • 4 Purposes of Prototypes: • Proof-of-concept: • Developing function of the product to compare with the goals • Learning tool • Proof-of-product: • Refine the components and assemblies • Geometry, materials and manufacturing processes are as important as functions • Rapid prototyping and CAD models have greatly improved the time and cost efficiency in building prototypes. • Proof-of-process: • Verify both the geometry and manufacturing process. • Exact materials and manufacturing processes are used to build sample for functional testing. • Proof-of-production • Verify the entire production product. • The result of preproduction run.

46. Types of Models An important decision in planning the project: -How many models and prototypes should be scheduled in the design process? Because of cost effectiveness, there is a strong move toward replacing physical prototypes with computer models. But not always right. Be sure to set realistic goals for the time required and the information learned.

47. Five Steps in Planning • Step 1: Identify the Tasks • Tasks in terms of the activities that need to be performed (generate concepts, producing prototypes, etc.) • Make the tasks as specific as possible. • Step 2: State the Objective for Each Task • Each task must be characterized by a clearly stated objective • The results of the tasks (or activities) should be the stated objectives. • Task objectives should be: • Defined as information to be refined or developed and communicated to others. • This information should be contained in deliverables • Easily understood by all in the design team. • Specific in terms of exactly what information is to be developed. If concepts are required, then tell how many are sufficient. • Feasible, given the personnel, equipment, and time available • Step 3: Estimate the Personnel, Time, and Other Resources Needed to meet the Objectives • Step 4: Develop a sequence for the tasks • Step 5: Estimate the Product Development Costs

48. Step 3: Estimate the Personnel, Time, and Other Resources Needed to Meet the Objective • Necessary Identification for each Task: • Who on the design team will be responsible for meeting the objectives? • What percentage of their time will be required? • Over what period of time they will be needed? • Time (in hours) = A x PC x D0.85 • A = a constant based on past projects • A = 30 for a small company with good communication • A = 150 for a large company with average communication • PC = product complexity based on function PC =  j x Fj (j = the level in the functional diagram; Fj = the number of functions at that level) • D = project difficulty • D = 1, not too difficult; D = 2, difficult; D = 3, extremely difficult • Time estimation = (o + 4m + p)/6 • O = optimistic estimate; m = most-likely estimate; p = pessimistic estimate • Time Distribution across the Phases of the Design Process • Project Planning (3 –5 %); Specifications Definition (10 – 15%); Conceptual Design (15 – 35%); Product Development (50 – 70%); Product Support (5 – 10%)

49. Step 4: Develop a Sequence for the Tasks • The goal is to have each task accomplished before its result is needed and to make use of all of the personnel, all of the time. • For each task, it is essential to identify its precessors and successors. • Tasks are often interdependent – two tasks need decisions from each other in order to be completed. • Sequential vs. Parallel (uncoupled and coupled) tasks • Bar Chart (or Gantt Chart) – best way to develop a schedule for a fairly simple project • Design Structure Matrix (DSM) – for a complex project with coupled tasks • Showing the relationship (or inter-dependence) among tasks (example: see page 104 • Useful tool for to help sequence the tasks (Page 104)

50. Step 5: Estimate the Product Development Cost • The planning document can serve as a basis for estimating the cost of designing the new product in terms of: • Personnel cost • Resources (supplies and equipment) • Team Project: • Planning must be done and written in the PDF. • Read examples in pages from 105 – 109 for planning. • - Gantt chart or DSM should be good entries.