Post on 17-Dec-2015
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Engineering Design
Brief Case Study: What is the Engineering Design Process and
Why is it Critical?
Rochester Institute of TechnologyMechanical Engineering Department
Rochester, NY USA
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Questions…
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Session Objectives
• Design process overview• Problem statement• Voice of the Customer• Voice of the Engineer• Generate and Select Concept
R . I . TMechanical Engineering
Session Objectives
• Design process overview• Problem statement• Voice of the Customer• Voice of the Engineer• Generate and Select Concept
R . I . TMechanical Engineering
Design Process(Ulrich & Eppinger Exhibit 2-2)
• Phase 0: Planning
• Phase 1: Concept Development
• Phase 2: System-Level Design
• Phase 3: Detail Design
• Phase 4: Testing and Refinement
• Phase 5: Production Ramp-Up
DPM
MSD I
MSD II
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Planning (U&E)
• Doing this now!• Identify market opportunities• Consider product platform and architecture• Assess new technologies• Research available technologies• Identify production constraints
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Concept Development (U&E)
• Identify Customer Needs• Establish Target Specifications• Generate Product Concepts• Select Product Concepts• Test Product Concepts• Set Final Specifications
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Session Objectives
• Design process overview• Problem statement• Voice of the Customer• Voice of the Engineer• Generate and Select Concept
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“We need a better ladder”
• Take 2 minutes and design a better ladder.
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Read handout
• What’s changed…?
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Session Objectives
• Design process overview• Problem statement• Voice of the Customer• Voice of the Engineer• Generate and Select Concept
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Read handout
• What’s changed…?• Customer/market • Can capture the Voice of the Customer
• Take 4 minutes• Write a set of 4-5 customer needs for your client.
• Prepare a brief statement to the class: describe customer and needs.
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“We need a better ladder”
• Take 2 minutes and design a better ladder
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Was this easier?
• Hopefully yes!
• Can we do better? Yes!
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---Break---
• Take 10 minutes and come back for the Voice of the Engineer
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Session Objectives
• Design process overview• Problem statement• Voice of the Customer• Voice of the Engineer• Generate and Select Concept
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Voice of the Engineer
• Functional decomposition:• What functions does the product/process need to
perform?
• What constraints are present?
• Core function of a ladder (all scenarios)?
• Ask, “How is the device going to do that?”
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Function Tree
• Take 5 minutes and come up with a list of functions that YOUR ladder needs to perform• Function is an active statement: verb-noun
• Note: We will spend more time on this in class, so don’t worry if it’s not perfect today!
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Metrics and Specifications
• How are you going to measure how well those functions are performed? (Metric)
• What is your threshold for success? (Specification)
• These require feasibility analysis
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Session Objectives
• Design process overview• Problem statement• Voice of the Customer• Voice of the Engineer• Generate and Select Concept
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Concept Generation
• Take 2 minutes: each team member brainstorm how to perform a single function on your ladder’s function tree• Ex: 5 team members can develop ideas for 5 functions
• The process has provided structure for solving your problem – this should be much easier!
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Morphological Chart
• A tool that will allow you to assemble complete system ideas from your list of function concepts.
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Function A Function B Function C Function D
A1 B1 C1 D1
A2 B2 C2 D2
A3 B3 C3 D3
A4 B4 C4 D4
Functions
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Design a Better Ladder
• These system concepts are ideas for better ladders.
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Concept Selection
• Take 2 minutes and decide which concept is the best
• What was your team’s process?
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Selection Criteria
• Evaluate each system concept against a predetermined set of criteria
• Objective, not subjective• May require some feasibility analysis• Allows you to look at the good and bad of each
system, and iterate and improve on your ideas• You will not do a complete concept selection in
DPM!
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Hand-Off from DPM to MSD
• You are now delivering a well-thought-out project.
• You know there are feasible solutions• You have reviewed the customer needs and
specifications• You are more confident that you are solving the
correct problem.
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Design Process(Ulrich & Eppinger Exhibit 2-2)
• Phase 0: Planning
• Phase 1: Concept Development
• Phase 2: System-Level Design
• Phase 3: Detail Design
• Phase 4: Testing and Refinement
• Phase 5: Production Ramp-Up
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Questions?