Lean product development

Question 1

what is set-based design process?

Answer 1

Three strategies:

1. Gradually narrow the initial requirements
2. Aggressively test the concepts to eliminate inferior alternatives
3. Reduce the extensions/space of each concept through development work, testing

Question 2

A common design problem?

Answer 2

we cannot simultaneously optimize everything

Question 3

What is a trade-off curve?

Answer 3

1. Relating different variables
   - often counteracting variabels
2. find the form of the curve through tests or mathematical relationships

(the curve changes with time)

Question 4

Michael Kennedy LPD process?

Answer 4

Knowledge buildup in time
—> run projects to build things with the knowledge
—> each project will become Better and better with knowledge and time

Question 5

LAMDA?

Answer 5

Learning cycle of knowledge creation
- look
—> go and see
- ask
—> why? and who knows?
- model
—> visualize knowledge and models
- discuss
—> get input and decide
- act
—> implement your decision

Question 6

LPD according to Jeffrey Liker

Answer 6

The triangle:
1. skilled people
2. process
3. Tools and technology
are the main focus to be able to have a lean product development system
(with more on skilled people/ management applications than other methods)

Question 7

How can we shorten the time to market at the same time as we get premium product quality?

Answer 7

1. Lean production

2. Lean product development (LPD)

Question 8

name some good reasons to shorten the “time to market”!

Answer 8

1. First on the market opportunity
   —> become top seller
   —> possibility to charge a comparatively high price
   —> set technology standard
2. The product development process aims at a moving target
   —> need for continuous change and improvement
   —> the quicker PD process, more accurately launching
3. Keep up with competitors
4. Cost,
   —> Engineering time is expensive

Question 9

What is the Toyota philosophy?

Answer 9

Product development is not about developing cars, it is about developing KNOWLEDGE about cars

Question 10

How is the work done according to the Toyota philosophy?

Answer 10

1. keeping everything simple
2. Making it visible
3. Trusting everybody to do the right thing

Question 11

Problems with listening to customers?

Answer 11

1. Customers are bad at innovations
   —> extending knowledge a step further is not developing science (faster horses ideas did not result in the locomotive)
2. The customer often mix up true quality and substitute quality
   —> thinks they want a bigger engine because they want higher speed but maybe they rather need optimized streamline design eg.

Question 12

What is the difference between True quality (TQ) and substitute quality (SQ)?

Answer 12

True quality is what the customer really wants but instead they often ask for substitute quality believing that SQ is a prior condition of true quality (TQ)

Question 13

Name some often observed PROBLEMS in western PD projects?

Answer 13

1. schedules, detailed requirements and system concept are set early
2. Decisions on the product are made
   —> before customer needs are well understood
   — >without understanding why past product failed
   —> before feasibility is proven

Question 14

How do western companies spend their PD time?

Answer 14

• 20% value adding
• 20% not value adding but neccessary
• 60% waste

Question 15

give some examples of waste?

Answer 15

1. poor tools and methods
   —> e.g. not using experimental methodology
   —> making too many experiments instead of putting time on designing the experiments
2. Wishful thinking
   - making decisions without data
   - discarding knowledge
   —> “unsuccessful” experiments ( but there is no such thing)
   —> not properly documenting
   —> “dead ends”
   - testing to specifications
   —> missing relevant circumstances and perspective that we have missed in the specification

Question 16

What does discarding of knowledge usually depend on?

Answer 16

Lack of understating and useful systems and routines for capture proper storage, generalization, dissemination and reuse of knowledge

Question 17

How should we make PD tests?

Answer 17

Always test to failure!

• Always susccessively increasingly the variable until something “breaks” reach a sure limit
• always try to find limits

Question 18

why are design limits important to know?

Answer 18

because if we stay within the limits when we design our product won’t break

Question 19

Name some differences between experimenting with traditional product development and lean product development!

Answer 19

1. Number of concept
Traditional:
—>one/few concepts: 
Lean:
—> many concepts

2. experiment method
Traditional:
—> non-destructive methods
Lean: 
—> test to failure

3. Experimental stage in the PD process
Traditional: 
—> late
Lean: 
—> early

4. economical perspective
Traditional: 
—> complicated and expensive
Lean: 
—> simple and inexpensive
5. Why we experiment
Traditional: 
—> to VERIFY something we think we already know
Lean: 
—> to learn things we don't know

Question 20

what did the Wright Brothers want to do?

Answer 20

To build a manned, heavier-than-air flying device

Question 21

What knowledge gaps did the wright brothers identify?

Answer 21

1. How can we create lift?
2. How can we create propulsion?
3. How can we control the device in flight?

Question 22

What did the wright brothers use for their experiments?

Answer 22

1. kite
2. manned gliders
3. airfoil models on bicycles
4. windtunnels

Question 23

What did the wright brothers have to design?

Answer 23

1. an engine
2. propellers (good even by todays standards)
3. wing warping to control the airplane

Question 24

In what sense did the wright brothers use a lean knowledge-based approach?

Answer 24

1. they acquired knowledge before they designed
2. They experimented at an early stage to gain knowledge
3. they used simple and inexpensive experimenting

Question 25

Describe the Write Brothers PD process!

Answer 25

TDB (Test- Design- Build) -Test to learn 1. Decide on what to accomplish but not the solution —> solution-independent problem formulation 2. Study the existing knowledge —> which might turn out to be incorrect 3. identify the key problems to solve 4. identify the knowledge gaps 5. Close the knowledge gaps —> learn through inexpensive and safe experimentation and testing of components to understand performance and limitations 6. Base design choices on what you have learned —> knowledge-based design 7. Design and build the full product

Question 26

what is set-based concurrent engineering?

Answer 26

1. try to come up with as many alternative solutions as you can 2. Successively eliminate inferior alternatives 3. Make all necessary decisions as late as possible

Question 27

What does set in set-based concurrent engineering mean?

Answer 27

1. The set of technically different concepts | 2. The set of different alternatives without within each concept, represented by different parameter combinations

Question 28

what can we say about meticulously recorded data?

Answer 28

Non-glamorous lab work is absolutely crucial to the success of a project

Question 29

Name an advantage of set-based data?

Answer 29

Set-based data from LPD experiments can in many cases also be generalized to represent many other cases! —> which adds further value

Question 30

name some various ways of describing the concepts?

Answer 30

1. collection of data from experiments 2. diagrams 3. sketches

Question 31

How can a trade-off curve be pushed into the "not possible right now" area,

Answer 31

1. through further development of the existing design | 2. Through development of new concepts, with or without new technology

Question 32

What does it mean when a trade-off curve is pushed into the "not possible right now" area?

Answer 32

It means that a concept has better performance

Question 33

What are trade-off curves primary a tool for within Toyota?

Answer 33

1. Understand 2. Communication —> between developers and managers 3. Communication and negotiation —> between specialists and functions (?) —> between customers and suppliers 4. Train new engineers 5. Record knowledge 6. Conduct design reviews 7. Design quality into the product 8. tool to compare data

Question 34

what can we see from the stress analysis diagram regarding the stress in the cylindrical tank? (PPT- t/D=sqrt(3/4)*p/sigma_b))

Answer 34

1. Safe area above the line (it won't break) —> design space 2. The wall thickness increases directly proportional to the diameter for constant pressure and fracture stress 3. If the ratio t/D is kept constant, the pressure can be increased directly proportional to the fracture stress 4. If the ratio (t/D)/(p/sigma_b) is constant, any of the four variables can be expressed in the other three 5. We have a tool for comparing data from different tank ruptures in the hope of finding a pattern

Question 35

How does a constant safety factor impact the trade-off(?) curve?

Answer 35

The curve gets steeper

Question 36

In what way can we use the diagram (trade-off curve?) to illustrate the operating conditions?

Answer 36

The location of the point of operation gives us a visual impression of the safety margin

Question 37

Name some possibilities to increase the safety margin for the stress in cylindrical tank problem? (make the curve steeper) - t/D=(sqrt(s)/4)*(p/sigma_b)

Answer 37

1. Increasing the fracture stress (sigma_b) at the same pressure 2. Lower pressure (decrease the pressure/stress ratio) 3. Make the wall thicker 4. Decrease the diameter (increase the thickness/diameter ratio)

Question 38

What is within the R&D scope and engineering scope within a lean product development process?

Answer 38

R&D: Continuous development of existing knowledge and development of new —> test to failure —> gain a knowledge base Engineering: Application of knowledge within a project —> Generate concepts, combine, find more limits, evaluate and eliminate —> further develop —> documentation and feedback of new knowledge from the project