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Unit II:

Unit II Murphology of design, divergent, transformation and convergent phases of product design, identification of need, Analysis of need. Design criteria; functional, aesthetics, ergonomics, form, shape, size, colour. Mental blocks, Removal blocs, Ideation techniques, Creativity, Check list.

Morphology of Design:

Morphology of Design Phase I: feasibility study Phase II: Embodiment Design Phase III: Detail Design Phase IV: Planning for Manufacture Phase V: Planning for Distribution Phase VI: Planning for Use Phase VII: Planning for Retirement of the Product

Phase I: Feasibility study:

Phase I: Feasibility study The producer has to undertake the detailed feasibility investigation which comprising two feasibility studies: i) The Technical Feasibility Study ii) The Economic Feasibility Study

- Technical Feasibility:

- Technical Feasibility Technical Feasibility Study covers the following aspects: Location of the project Lay-out of the Plant Size of the Plant Factory construction Manufacturing process / Technology Process Design Product Design Scale of Operation Infrastructural facilities

Economic Feasibility:

Economic Feasibility The prime objective of setting up a project is to derive a fair return on the investment. Economic Feasibility Study, therefore, concerns itself with matching of economic resources with the physical requirements of a project and determining the viability of investment therein.

Phase II: Conceptual (preliminary) Design:

Phase II: Conceptual (preliminary) Design Identification of customer needs Problem definition Gathering information Conceptualization scope selection Refinement of the PDS

Phase II: Embodiment Design:

Phase II: Embodiment Design Product architecture Configuration design of parts and components Parametric design of parts and components

PowerPoint Presentation:

Define problem Problem statement Benchmarking QFD PDS Project planning Gather information Internet Patents Trade literature Concept generation Brainstorming Functional decomposition Evaluation of concept Decision matrices Product architecture Arrangement of physical elements to carry out function Detail design Detailed drawings and specifications Configuration design Prelim. selection of material and mfg. Modeling and sizing of parts Parametric design Robust design Tolerances Final dimension DFM Conceptual Design Embodiment Design

Phase IV: Planning for Manufacture:

Phase IV: Planning for Manufacture Designing specialized tools and fixtures Specifying the production plant that will be used Planning the work schedules and inventory 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 :

Phase V: Planning for Distribution Designing the packaging of product Planning of warehousing of product Planning for promotional activity Designing the product for condition arising in distribution.

Phase VI: Planning for Use :

Phase VI: Planning for Use Design for reliability Design for safety Design for maintenance Design for ease in use Design for aesthetic feature Design for operational economy Design for adequate duration for service

Phase VII: Planning for Retirement of the Product:

Phase VII: Planning for Retirement of the Product Design to reduce the rate of obsolescence by taking into account the anticipated effect of technology development Design physical life to match anticipated service life. Testing of serviced part in laboraty for design perpose.

Need Identification:

Need Identification

Types of Design Project:

Types of Design Project Variation of an existing product Improvement of an existing product Development of a new product for a low-volume production run Development of a new product for mass production One-of-a-kind design

How to Gathering Information from Customer:

How to Gathering Information from Customer Interview with customer Focus group Customer surveys Customer complaints

Levels of Customer Requirements:

Levels of Customer Requirements Expecters: the basic attribute that one would expect to see in the product Spokens: the specific features that the customers say they want in the product Unspokens: the product attributes the customer does not generally talk about, but are nevertheless are important to him or her Exciters or delighters: the features that make the product unique and distinguish it from the competition

PowerPoint Presentation:

From customer requirement to production planning

Concept Generation and Evaluation:

Concept Generation and Evaluation

PowerPoint Presentation:

Problem decomposition Explore fore ideas Explore systematically Morphological chart External to team Internal to team Brain-storming Absolute criteria Go-no-go screening Relative criteria Pugh concept selection Decision matrix Analytical hierarchy process Best concept Concept Generation Evaluation


Creativity Develop a creative attitude Unlock your imagination Be persistent Develop an open mind Suspend your judgment Set problem boundary

Vertical and lateral thinking:

Vertical and lateral thinking Vertical thinking Lateral thinking Only one correct solution Many possible solutions Analytical process Nonjudgmental Movement is made in a sequential, rule-based manner Movement is made in a more random pattern If a positive decision cannot be made at a step, progress stop If a positive decision cannot be made at a step, thinking jump Follow most likely decision path Follows all paths Deals only with reality as science know it today Can create its own reality Classification and label are rigid Reclassifies objects to generate ideas


Invention Invention is something novel and useful, being the result of creative thought. Classified into 7 categories The simple or multiple combination Labor-saving concept Direct solution to a problem Adaptation of an old principle to an old problem to achieve a new result Application of a new principle to an old problem Application of a new principle to a new use Serendipity

Psychological View of Problem Solving:

Psychological View of Problem Solving Four-stage model Preparation : The element of the problem are examined and their relations are studied. Incubation : You “sleep on the problem.” Inspiration : A solution or a path toward the solution suddenly emerges. Verification : The inspired solution is checked against the desired result.

Creativity Methods:

Creativity Methods

Mental Block:

Mental Block Perceptual blocks Stereotyping Information overload Limiting the problem unnecessarily Cultural blocks Environmental blocks Emotional blocks Fear of risk taking Unease with chaos Adopting a judgmental attitude Unable or unwilling to incubate Intellectual blocks


Brainstorming Four fundamental brainstorming principles Criticism is not allowed. Ideas brought forth should be picked up by other people present. Participants should divulge all ideas entering their minds without any constraint. A key objective is to provide as many ideas as possible within a relatively short time.

Stimulation of ideas:

Stimulation of ideas Combination: What new ideas can arise from combining proposes and functions? Substitution: What else? Who else? What other place? What other time? Modification: What to add? What to subtract? Change color, material, motion, shape? Elimination: Is it necessary? Reverse: What would happen if we move it backward? Turn it upside down? Inside out? Other use: Is there a new way to use it?

Creative Idea Evaluation:

Creative Idea Evaluation

Theory of Inventive Problem Solving (TRIZ):

Theory of Inventive Problem Solving (TRIZ) TRIZ is Russian acronym Developed by Genrich Altshuller and his coworkers in Russia, since 1946 About 1.5 million patents were studied, and discovered that only a few dozen inventive principles were used for solving the problems

Five levels of problem solutions:

Five levels of problem solutions Level 1: Routine design solutions arrived at methods well known in the specialty area. 30% Level 2: Minor correction to an existing system by methods know in the industry. 45% Level 3: Fundamental improvement to an existing system which resolve contradictions within the industry. 20% Level 4: Solution based on application of new scientific principle to perform the primary function of the design. 4% Level 5: Pioneering inventions based on rare scientific discovery. 1% TRIZ is aimed at improving design concept at levels 3 and 4

Engineering Parameters used:

Engineering Parameters used Weight of moving object Weight of nonmoving object Length of moving object Length of nonmoving object Area of moving object Area of nonmoving object Volume of moving object Volume of nonmoving object Speed Force Tension, Pressure Shape Stability of object Strength Durability of moving object Durability of nonmoving object Temperature Brightness Energy spent by moving object Energy spent by nonmoving object

Engineering Parameters used:

Engineering Parameters used Power Waste of energy Waste of substance Loss of information Waste of time Amount of substance Reliability Accuracy of measurement Accuracy of manufacturing Harmful factors acting on object Harmful side effects Manufacturability Convenience of use Repairability Adaptability Complexity of device Complexity of control Level of automation Producibility

The Inventive Principles:

The Inventive Principles Segmentation Extraction Local quality Asymmetry Combining Universality Nesting Counterweight Prior counteraction Prior action Cushion in advance Equipotentiality Inversion Spheroidality Dynamicity Partial or overdone action

The Inventive Principles:

The Inventive Principles Moving to a new dimension Mechanical vibration Periodic action Continuity of useful action Rushing through Convert harm into benefit Feedback Mediator Self-service Copying An inexpensive short-lived object instead of an expensive durable one Replacement of a mechanical system

The Inventive Principles:

The Inventive Principles Use of a pneumatic or hydraulic construction Flexible film or thin membranes Use of porous material Change the color Homogeneity Rejecting and regenerating part Transformation of physical and chemical states of an object Phase transition Thermal expansion Use strong oxidizers Inert environment Composite materials


Example A metal pipe was used to pneumatically transport plastic pellets. A change in the process required that metal powder now be used with the pipe instead of plastic. The harder metal powder causes erosion of the inside of the pipe at the elbow where the metal particles turn 90 o . Conventional solutions to this problem might include reinforcing the inside of the elbow with an abrasion-resistant hard-facing alloy, providing for an elbow that could be easily replaced after it has corroded, or redesigning the shape of the elbow. However, all of these solutions require significantly extra costs, so a more creative solution was sought.


Solution What is the main function of our elbow? To change the direction of flow of metal particle What we want to improve? Increase the delivered particles’ speed (parameter 9) Reduce the energy required (parameter 19)


Solution Degrade parameter Parameter number Inventive principle used Force 10 13, 28, 15, 19 Durability 15 8, 3, 26, 14 Temperature 17 28, 30, 36, 2 Energy 19 8, 15, 35, 38 Loss of matter 23 10, 13, 28, 38 Quantity of substance 26 10, 19, 29, 38 Degrade parameter Parameter number Inventive principle used Convenient to use 35 28, 35, 30 Loss of time 25 15, 17, 13, 16 Improving speed Improving energy


Solution By counting the frequency of inventive principles suggested, the Principle 28 is the most cited (4 times). The others Principles cited are 13(3), 15(3), and 38(3). Then Principle 28 shall be firstly considered.


Solution The full description of Principle 28 is 28 Replacement of a mechanical system Replace a mechanical system by an optical, acoustical, or odor system. Use an electrical, magnetic, or electromagnetic field for interaction with the object. Replace fields. Example: (1) stationary field change to rotating field; (2) fixed fields become fields that change in time; (3) random fields change to structural one. Use a field in conjunction with ferromagnetic particles. Then possible solution may be placing a magnet at the elbow to attract and hold a thin layer of powder that will serve to absorb the energy of particles navigating the 90 o bend, thereby preventing erosion of the inside wall of the elbow.

Algorithm of Inventive Problem Solving:

Algorithm of Inventive Problem Solving Formulate initial physical contradiction Original problem statement Formulate technical contradiction Analysis of conflict domain & resource Formulate ideal solution Formulate main contradiction Method of elimination of Physical contradiction Reformulation of problem statement NO SOLUTION SOLUTION Knowledge base of effects

Conceptual Decomposition:

Conceptual Decomposition It is common tactic to decompose the problem into smaller parts. Connections of elements in terms of structure and function within the blocks shall be stronger than those between the blocks. There are two main approaches Decomposition in the physical domain Functional decomposition

Decomposition in the Physical Domain:

Decomposition in the Physical Domain Bicycle Frame Seat Wheels Brakes Gears Rim Spokes Tire Decompose the product into subassemblies and components that are essential for the all functioning of the product. Need to understand the interactions and connections that each of these subassemblies and elements has with each other. The connection can be physical, energy, or force connection.

Functional Decomposition:

Functional Decomposition Function is in the nature of a physical behavior or action Function tells us that what the product must do. The process of functional decomposition describes the design problem in term of a flow of energy, material, and information.

PowerPoint Presentation:

Device Input Function Other effects Output Nozzle Fluid flow Increase velocity of fluid Decrease pressure of fluid Fluid flow Motor Electrical energy Convert electrical energy to rotating mechanical energy Thermal energy generated Rotating mechanical energy Switch Mechanical energy Separate or joint contact Flow of electricity enabled or stopped Position of contact moved Gear Rotating Mechanical energy Change speed of rotation Change direction of rotation Rotating Mechanical energy Room thermostat Flow of room air Separate or joint contact Flow of electricity enabled or stopped Position of contact moved Wrench Energy Increase magnitude of force or torque Energy Functionality of some common device

PowerPoint Presentation:

Subfunctions required to open and close CD case 1 Open case 2 Extract CD 3 Extract leaflet 4 Replace CD 5 Replace leaflet 6 Close case 7 Store case

Generating Design Concept:

Generating Design Concept

Morphological Chart:

Morphological Chart Proposed by Zwicky Steps to follow Arrange the functions and subfunctions in logical order List for each subfunction “ how ” Combine concepts

Example “CD case”:

Example “CD case” Subfunction Concept 1 2 3 4 5 1.0 Open case 1.1 Hold and grip case Flat box Groove box Curved box Case with handle Rubber grip strips 1.2 Disengage lock Friction lock Inclined plane lock Magnetic lock Clamp lock Clicking hinge lock 1.3 Expose CD Conventional hinge One-piece flex plastic hinge Slide-out, like match box Tilt like shampoo bottle top 2.0 Extract CD 2.1 Disengage from securing system Conventional Rosetta Lift/lock device Padded cradle 2.2 Grasp CD and remove Hand

PowerPoint Presentation:

Subfunction Concept 1 2 3 4 5 3.0 Extract leaflet 3.1 Disengage from securing system Tabs Holding slot Velcro straps Tab that swivels No securing system 3.2 Remove leaflet Hand 4.0 Replace CD 4.1 Place CD in securing system Hand 4.2 Engage securing system 2-finger push Whole hand Example “CD case”

PowerPoint Presentation:

Subfunction Concept 1 2 3 4 5 5.0 Replace leaflet 5.1 Place leaflet in securing system Slide into position Lay in position 5.2 Engage securing system Slide under tabs or in slot Swivel tabs Attach Velcro 6.0 Close case 6.1 Engage lock Friction surfaces Put magnet together Slide platen into position 7.0 Store case 7.1 Place case in desired location Put on table Put on another CD Put in special CD holder Example “CD case” The combinations of these concepts generate many possible solutions for the design. There are 162,000 combinations in this design .

PowerPoint Presentation:

Assume that 5 concepts are drawn from the previous chart. Concept 1: Conventional square box (1) , with the incline plane lock (2) and a slide-out matchbox (3) for a hinge. The CD is secured with a conventional “rosetta” (1) while the leaflet is secured with tab (1) . Concept 2: A streamline curved box to fit the hand (3) , with a friction lock (2) and a conventional hinge (3) . The CD is secured in padded elastomer cradle (3) and the CD case are designed to stack flat (2) . Concept 3: The box is grooved to the shape of the finger (2) , with a magnetic lock (3) and conventional hinges (1) . A new lift/lock secures the CD (2) . The leaflet fits in a slot in the top of the case (2) . Concept 4: A standard square box (1) with magnetic lock (3) and conventional hinges (1) . The CD is secured with a padded cradle (3) , while the leaflet is secured with Velcro straps (3) . Concept 5: A curved box (3) with inclined plane lock (2) , with a slide-out matchbox (3) . The CD is held by a rosetta (1) and the leaflet fits into a slot (2) . The cases are designed to stack (2) .

Axiomatic Design:

Axiomatic Design Developed by Professor Nam Suh and his colleagues at MIT Focus around 2 design axioms Axiom 1: The independent axiom Maintain the independence of functional requirements (FRs). Axiom 2: The information axiom Minimize the information content.

Mapping process of Suh’s concept:

Mapping process of Suh’s concept Functional Requirements FR 1 FR 2 FR 3 Design Parameters DP 1 DP 2 DP 3 DP 4

Hierarchy of FRs for a metal cutting lathe:

Hierarchy of FRs for a metal cutting lathe Metal removal device Power supply Workpiece rotation source Speed- changing device Workpiece support and toolholder Support structure Tool positioner Support structure Positioner Tool holder Tool holder Rotation stop Longitudinal clamp

Hierarchy of lathe design in physical domain:

Hierarchy of lathe design in physical domain Lathe Motor drive Head stock Gear box Tailstock Bed Carriage Frame Feed screw Spindle assembly Bolt Handle Clamp Tapered bore Pin

PowerPoint Presentation:

7 corollaries are derived from the 2 axioms mentioned before Corollary 1: Decoupling of a coupled design Decouple or separate parts or aspects of a solution if FRs are coupled or become interdependent in the proposed design. Corollary 2: Minimize FRs Minimize the number of FRs and constraints. Corollary 3: Integration of physical parts Integrate design features in a single physical part if FRs can be independently satisfied in the proposed solution . Corollary 4: Use of standardization Use standardized or interchangeable parts if the use of these parts is consistent with the FRs and constraints. Corollary 5: Use of symmetry Use symmetric shapes and/or arrangement if they are consistent with the FRs and constraints. Symmetrical parts require less information to manufacture and to orient in assembly. Corollary 6: Largest tolerance Specify the largest allowable tolerance in stating FRs. Corollary 7: Uncoupled design with less information Seek an uncoupled design that requires less information than coupled designs in satisfying a set of FRs.



Comparison Based on Absolute Criteria:

Comparison Based on Absolute Criteria Evaluation based on judgment of feasibility of the design. Concept should be into one of three categories: It is not feasible? Next question is “Why is it not feasible?” It is conditional –it might work if something else happen? Looks as if it will work, then it seems worth to work further.

Comparison Based on Absolute Criteria:

Comparison Based on Absolute Criteria Evaluation based on assessment of technology readiness. The technology used in the design must be mature enough not to need any additional research. Their indicators are Can the technology be manufactured with known processes? Are the critical parameters that control the function identified? Are the safe operating latitude and sensitivity of the parameters known? Have the failure modes been identified? Does hardware exist that demonstrates positive answers to the above four questions?

Comparison Based on Absolute Criteria:

Comparison Based on Absolute Criteria Evaluation based on go-no-go screening of the customer requirements. After a design concept has passed filters 1 and 2, the emphasis shifts to establishing whether it meets the customer requirements framed in the QFD Each requirement must be transformed into a question to be addressed to each concept. The questions should be answerable as either yes (go) , maybe (go) , or no (no-go) . The emphasis is not on a detail examination but on eliminating any design concepts that clearly not able to meet an important customer requirement .

Pugh’s Concept Selection Method:

Pugh’s Concept Selection Method Choose the criteria by which the concepts will be evaluated Formulate the decision matrix Clarify the design concept Choose the datum concept Run the matrix Evaluate the rating Establish a new datum and rerun the matrix Plan further work Second working session

PowerPoint Presentation:

Example of CD case Criterion Concept 1 Concept 2 Concept 3 Concept 4 Concept 5 Std. CD case Mfg. cost S - S - S D A T U M Easier opening + S S S + Easier to remove leaflet S S - + - Easier to remove CD S + + + S Hinge doesn’t come apart + S S S + Stacking stability S S S S + More secure locking + S + + + Fits hand better S + + S +  + 3 2 3 3 5  - 0 1 1 1 1  S 5 5 4 4 2

Measurement Scales:

Measurement Scales Design objectives A B C D E Row total A - 1 0 0 1 2 B 0 - 1 1 1 3 C 1 0 - 0 0 1 D 1 0 1 - 1 3 E 0 0 1 0 - 1 10 Pairwise Comparison method Assume 5 design objectives to be compared

Weighted Decision Matrix:

11-point scale Description 5-point scale Description 0 Totally useless solution 0 Inadequate solution 1 Very inadequate solution 2 Weak solution 1 Weak 3 Poor solution 4 Tolerable solution 2 Satisfactory 5 Satisfactory solution 6 Good solution with a few drawback 7 Good solution 3 Good 8 Very good solution 9 Excellent (exceed the requirement) 4 Excellent 10 Ideal solution Weighted Decision Matrix

PowerPoint Presentation:

Example of Steel Crane Hook A heavy steel crane hook, for use in supporting ladles filled with molten steel as they are transported through the steel mill, is being designed. Three concepts have been proposed: (1) built-up from steel plates, welded together; (2) built-up from steel plates, riveted together; (3) a monolithic cast-steel hook. The design criteria investigated are (1) material cost, (2) manufacturing cost, (3) time to produce another if one fails. (4) durability, (5) reliability, (6) reparability. Crane hook O 1 =1.0 Cost O 11 =0.6 Quality in service O 12 =0.4 Mat’l cost O 111 =0.3 Mfg. Cost O 112 =0.5 Reparability O 113 =0.2 Durability O 121 =0.6 Reliability O 122 =0.3 Time to produce O 123 =0.1 O xyz here are weighted factors

PowerPoint Presentation:

Weighted Decision Matrix for a steel hook Design criterion Weight factors Unit Built-up plates welded Built-up plates riveted Cast steel hook Mag. Score Rating Mag. Score Rating Mag. Score Rating Material cost 0.18 ¢/lb 60 8 1.44 60 8 1.44 50 9 1.62 Mfg. cost 0.60 $ 2500 7 2.1 2200 9 2.70 3000 4 1.20 Reparability 0.12 Exp Good 7 0.84 Excell. 9 1.08 Fair 5 0.60 Durability 0.24 Exp. High 8 1.92 High 8 1.92 Good 6 1.44 Reliability 0.12 Exp. Good 7 0.84 Excell. 9 1.08 Fair 5 0.60 Time to produce 0.04 Hr. 40 7 0.28 25 9 0.36 60 5 0.20 7.42 8.58 5.66 Mag. = Magnitude Exp. = Experience Excell. = Excellent

Analytical Hierarchy Process, AHP:

Analytical Hierarchy Process, AHP Multicriteria decision process introduced by Saaty Suited to hierarchically structural system Can work with both numerical and intangible and subjective factors Use pairwise comparison of the alternatives

PowerPoint Presentation:

Example of crane hook design using AHP approach Crane hook design Material cost Manufacturing cost Reliability Durability Reparability Time to produce Built-up plates, welded steel Built-up steel plates, riveted Cast steel Hierarchical structure of a crane hook design

PowerPoint Presentation:

Saaty’s fundamental scale for pairwise comparison Intensity of importance Definition Description 1 Equal importance Two activities contribute equally to the objective 3 Moderate importance Judgment and experience slightly favor one activity over another 5 Strong importance Judgment and experience strongly favor one activity over another 7 Very strong An activity is favored very strongly over another 9 Extreme importance The evidence favoring one activity over another is of the highest possible 2, 4, 6, 8 These rating are used to compromise between the above values.

PowerPoint Presentation:

Material cost Manufacturing cost Reparability Durability Reliability Time to produce Material cost 1 1/5 3 1/5 3 7 Manufacturing cost 5 1 7 3 3 7 Reparability 1/3 1/7 1 1/5 1/3 5 Durability 5 1/3 5 1 3 7 Reliability 1/3 1/3 3 1/3 1 7 Time to produce 1/7 1/7 1/5 1/7 1/7 1 Total 11.8 2.14 19.2 4.87 10.47 34 Square matrix to determine weighting factors

PowerPoint Presentation:

Material cost Manufacturing cost Reparability Durability Reliability Time to produce Material cost 0.085 0.424 0.028 0.424 0.028 0.012 1 Manufacturing cost 0.093 0.467 0.065 0.154 0.154 0.065 1 Reparability 0.156 0.364 0.052 0.260 0.156 0.010 1 Durability 0.041 0.616 0.041 0.205 0.068 0.029 1 Reliability 0.286 0.286 0.031 0.286 0.095 0.013 1 Time to produce 0.206 0.206 0.147 0.206 0.206 0.029 1 Total 0.867 2.363 0.364 1.535 0.707 0.158 6 Weighting factor (AVG) 0.144 0.394 0.061 0.256 0.118 0.026 1 Normalized values for square matrix

PowerPoint Presentation:

Now construct the decision matrix using previous values given. Built-up welded plates Built-up riveted plates Cast Manufacturing cost 2500 2200 3000 $/crane hook 400 454 333 Reciprocal x 10 -6 0.34 0.38 0.28 Fraction of total Built-up welded plates Built-up riveted plates Cast Reparability 6 10 1 Ranking 0.35 0.59 0.06 Fraction of total Durability Welded plate Riveted plate Cast Total Rating (Avg.) Welded plate 1.00 0.23 1/3 0.22 3.00 0.33 0.78 0.26 Riveted plate 3.00 0.69 1.00 0.65 5.00 0.56 1.90 0.63 Cast 1/3 0.08 1/5 0.13 1.00 0.11 0.32 0.11 Total 4.33 1.00 1.53 1.00 9.00 1.00 3.00 1.00

PowerPoint Presentation:

Final Decision Matrix for the Crane Hook Problem Design criterion Weight factor Welded plate Riveted plate Cast Welded plate Riveted plate Cast Material cost 0.14 0.31 0.31 0.38 0.043 0.043 0.053 Manufacturing cost 0.39 0.34 0.38 0.28 0.133 0.148 0.109 Reparability 0.06 0.35 0.59 0.06 0.021 0.035 0.004 Durability 0.25 0.26 0.63 0.11 0.065 0.157 0.027 Reliability 0.12 0.33 0.43 0.24 0.040 0.052 0.029 Time to produce 0.03 0.31 0.49 0.20 0.008 0.013 0.005 Total 1.00 0.31 0.45 0.23 Then riveted plate is the most appropriate alternative for this design

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