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8/12/2016 ISERC 2016 1
Getting Design Right
Peter L. Jackson
Systems Engineering Program
Cornell University
Motivation
• Why doesn’t everyone learn systems engineering?
• What are the impediments to dissemination?• Emphasis on complexity
• Engineering vs. design
• Document-centric
• What is the joy of systems engineering?
• What are the lessons from the Six Sigma movement?
Curriculum Requirements• Emphasize discovery, design, problem-solving, and validation
• Defer discussions of complexity until after a basic design methodology has been taught
• Describe the methodology as a design cycle of simple steps
• Blend the systems engineering approach with other customer-focused and product-development focused approaches
• Use action-oriented verbs to describe the steps
• Motivate each major design step with “What Went Wrong” case studies
• Restrict techniques to those requiring only secondary-school level mathematics and science
• Illustrate each step using a running example
• Reinforce systems thinking with repeated opportunities for abstraction (‘dive and surface’)
• Provide design challenges in both business and engineering applications
‘What Went Wrong’ Case Studies
The Vasa Warship
The Patriot Missile
The RelaxacisorBabbage Difference Engine
The Mars Orbiter
The Hubble Telescope
The International Space Station
http://www.traveljournals.net/pictures/l/18/188954-vasa-warship-at-the-vasa-muset-stockholm-sweden.jpg
http://www.museumofquackery.com/devices/images/relaxwoman.jpg
http://www.plyojump.com/classes/images/computer_history/analytical_engine_fragment.JPG
http://www.tcappsbct.com/BCT/img/Patriot_missile_launch.jpg
http://nssdc.gsfc.nasa.gov/image/spacecraft/mars98orb.jpg
http://www.dailyhotnews.org/wp-content/uploads/2010/04/hubble-telescope-752865.jpg
http://schsscience.files.wordpress.com/2009/06/international-space-station2.jpg
http://www.juvandesign.com/wp-content/uploads/2009/05/boeing1.jpg
http://lostcruiseliners.webs.com/0_paintings_titanic%5B1%5D.jpg
Boeing 787 Dreamliner
The ‘Titanic’
Running Example: Designing a Toy Catapult
http://static.letsbuyit.com/filer/images/uk/products/original/128/40/schleich-catapult-12840960.jpeg
Learn By Doing
• A Worked Example
• A Toy Catapult
• Suggested Projects
• Bathroom Cleaning Robot
• Meal Delivery Service
• Health Monitoring System
• Pedestrian Alert System
8/12/2016 ISERC 2016 10
Fundamental Views
Eight Steps
The House of Quality
The Vee Diagram
The Linked House of Quality
The Systems Cube
The Operations Description Template
The Context Diagram
Dive and Surface
• Applications of abstraction
• Functional requirements
• Voice of the customer
• Concept classification
• Subsystem identification
• Behavior threads to functional flow and state change
• Zachman architecture
8/12/2016 ISERC 2016 15
Small Group Activity
• Break into groups of 3-4
• Consider the following problem:• It is a cold night and you as a group have left a
restaurant at closing time. One of you was going to drive everyone home but your car keys are not in your pocket.
• Quickly decide as a team how you would organize to solve the problem• What are the steps?
• In what sequence?
• Can any steps be performed in parallel?
8/12/2016 ISERC 2016 16
Small Group Activity 2
• You are designing a meal delivery system• Unified menu of participating restaurants
• Single point of payment
• Coordinated pickup and delivery
• Managed fleet of vehicles and drivers
• Use an operation description template to describe the customer experience
• Identify use cases
• Construct a context matrix (or context diagram)
• Abstract functional requirements
8/12/2016 ISERC 2016 17
Virtues of “Getting Design Right”
• Better project scope
• Better project definition
• Focus on customer requirements
• Purposeful exploration of alternatives
• More successful integration and test
• Explicit consideration of risk
• Better project management
• Continuous improvement
Related Talk
• Systems Design Thinking: Integrating Effectiveness and Efficiency
• Sirietta Simoncini, Peter L. Jackson
• Systems Engineering Program, Cornell University
• Tuesday, May 24
• 5:00 pm, Adventure Room, Adventure Tower
8/12/2016 ISERC 2016 18
8/12/2016 ISERC 2016 22
Explore the Design Space
Provide working surface
Absorb power
Resist force
Rigid solid Terminator Fix to seabed
Flexible solid
Attenuator Balance wave forces
Gas Point absorber
Use inertia
Concept classification tree
Morphology box
8/12/2016 ISERC 2016 23
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Direction of Change ¯ ¯ ¯ Units Targets
Maximum launch velocity 0.5 XX XX XX ? XX XX mps 6
Maximum mass launch capability 0.5 XX √√ XX ? XX XX g 150
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Measurement Units
Optimize Design Choices
Pugh matrix
Optimization models