Design Process, Specification and Conceptual Design Flashcards
What does TRL stand for
Technology Readiness Level
TRL 0
Idea
TRL 1
Basic research
TRL 2
Technology formulation
TRL 3
Applied research
TRL 4
Small scale prototype
TRL 5
Large scale prototype
TRL 6
Prototype system
TRL 7
Demonstration system
TRL 8
First of a kind commercial system
TRL 9
Full commercial application
Which TRL do Universities deal with
0-4
Which TRL do Industries deal with
2-9
What makes products complicated
- Multi-part products
- Organisation of multi-disciplinary teams
- Products need verification and documentation
What are the 8 major objectives in car design
- Technical performance
- Cost
- Environmental
- Ergonomics
- Aesthetics
- Reliability
- Safety
- Luxury
Give an example of when form conflicted with function
Audi TT Rear wheel slip
Explain why Toyota recalled 2.1 million vehicles
Accelerator pedal could become trapped under floor mat resulting is high possibility of crashes. Cost - $2 billion
1 in how many cars purchased last month were electric
12
Give 4 examples of some key future developments
- Electric cars
- Robotics
- Renewable energy
- Domestic products
Name some engineering design consultancies in the UK
DCA Design, Cambridge Consultants, PA Consulting Group
What is the biggest industry in the UK
Automotive - £77.5 billion turnover, 814000 people employed, 12% of exported goods
Why is a design process needed
To systemically coordinate the efforts of large, multi-disciplinary teams
What are the 3 types of design
- Incremental
- Adaptive
- Original
What does incremental design involve
Minor changes/improvements to an existing product - low risk, common with mature products (eg cars). Enabled by new elements of technology and new manufacturing processes
What does adaptive design involve
Significant changes/improvements to whole sub-systems - common when significant technologies come along (eg airbags, computer controlled engines)
What does original design involve
Major changes/improvements to whole sub-systems or systems - Not common due to risk, only when acute need (eg energy concerns) (IC engine to hybrid)
Give the 9 stages of a product lifecycle
- Trigger
- Product Planning
- Feasibility study
- Design
- Development
- Production
- Distribution
- Operation
- Disposal
What are the 7 design stages of the Pahl and Beitz model
- Task
- Specification
- Concept
- Preliminary layout
- Definitive layout
- Documentation
- Solution
What are the 4 design phases of the Pahl and Beitz model
- Task clarification
- Conceptual design
- Embodiment design
- Detail design
Describe the Pahl and Beitz model
Top down design (start with abstract ideas, finish with complete details), distinct stages makes it manageable,, stages of design can be overlapped (concurrent) to reduce time
What are the 4 design stages of the Double Diamond process
- Discover (divergent)
- Define (convergent)
- Develop (divergent)
- Deliver (convergent)
Describe the Double Diamond process
Encourages task clarification as a major task involving significant research, breaks task into stages with outputs
What are the top and bottom sections of the V-model respectively
Systems design and Component design
What are the 6 stages of the V-model
- Concept of operations
- Requirements and architecture
- Detailed design
- Integration/Test/Verification
- System verification
- Operations and Maintenance
Describe the V-model
Top down during the design phase, Bottom up during verification and delivery phase
What are the advantages of top-down design
Helpful to plan system before deciding on the details
What is the advantage of bottom-up testing
No use testing the system if individual components are not right
What are the 4 phases of the stage gate model
- Definition
- Development
- Production
- In-service
Describe the stage gate model
Certain achievements are required to be completed before progress can be made, regular design reviews, performance of design can be defined and recorded, key managers can sign off progress
Why are prototype models important
Computer models have limitations, if a designer is unaware of weakness it will not be modelled, Cheap, Feedback on form and function quickly
What are the 4 prototype models
- Breadboard (technology feasibility)
- Engineering (main performance aspects)
- Qualification (entire performance + safety margins)
- Delivered (Actual product)
Give an example of when insufficient modelling was done
Hubble space telescope - wobble of solar array caused by inadequate thermal blankets (unknown unknown)
What are the advantages of a function means tree
Help convert abstract functions into specific sub-functions, high level objectives represent customer ‘wants’, identifies requirements, can be used for conceptual design
Name 3 case studies that involved an inadequate specification
Bristol rovers (Stand did not protect from rain), Challenger rocket (O-ring was too cold to keep seal), Concorde (Protection lining)
What are the 7 drivers of innovation
- New legislation
- Customer wishes
- Technology breakthroughs
- Innovators/Entrepreneurs
- Elite activities
- Affluence
- Competition
Name some conceptual design methods
Studying competition (iPhone vs Samsung)
Insight (Large chainwheel on Team GB bikes/Large ships)
Bio-inspiration (Velcro, bullet train, self-cleaning glass)
Technology transfer (Cyclone technology)
Functional decomposition
Backwards design (Worm gear set for spacecraft)
Prototyping
Brainstorming
Inversion (Helicopters, Caterpillar tracks)
Technology opportunities
Sketching
What are the advantages and disadvantages of Bio-inspiration
Concepts are proven to work in harsh environments, very large range of concepts - often very complex at micro level, not necessarily designed for longevity
What is functional decomposition
Identifying individual sub functions and sub solutions and displaying in a morphological chart to observe different combinations of solutions
What is brainstorming
Uninhibited idea creation by a team made up of people with different backgrounds. Encourages creativity
What is inversion and what are some examples of it
Seeing if an existing design can be done another way
What are some technology oppurtunities
AI, Mag-lev, Graphene, Sensors, Voice recognition
What are the advantages of sketching
Quick, record notes, teamwork, can record lots of options
What is TRIZ
Contradiction matrix used to obtain an ideal solution where all functions are achieved without causing any problem
What is backwards design and give an example of it
Identify an idealistic solution and work backwards from it (double action worm gear set for space craft)
What are the 4 design reviews?
Preliminary design review
Engineering design review
Qualification design review
Final design review
What is the difference between an objective and a constraint? Give examples of each.
An objective is something you aim to optimise e.g. attrictive efficient reliable
A constraint is something which limits the design in a way e.g. safety performance, emissions standards
What is physical insight? give an example
Understanding of physical laws help design choices
e.g inertial drag is influence by frontal area
What 5 types of vehicle suspension are there?
Leaf spring Macpherson Double wishbone Horizontal Pushrod
What 3 drive layouts are there?
Rear wheel
Front wheel
4 wheel
Name the two types of vehicle chassis
Monocoque
Body on frame
Name 5 ways you can transmit torque
- Keyway
- Spline
- Grub screw
- Bonding
- Wedge system
What 7 types of actuator are there?
- Electric
- Hydraulic
- Pneumatic
- Piezo
- Air muscle
- Memory alloy
- Dielectric elastomers
Give 4 examples of 4 bar mechanisms and their applications
Parallelogram (double glazed windows) Crank rocker (windscreen wipers) Over centre (pliers) Inverted parallelogram (knee)
What 3 ways can you reduce damping?
Added mass
Added damping
Tuning
