a short course Axiomatic Design An Introduction part

a short course Axiomatic Design: An Introduction (part one) Axiomatic Design Short Course Reykjavik University 18 October 2017 Prof. Christopher A. Brown Professor of Mechanical Engineering Worcester Polytechnic Institute Worcester, Massachusetts, USA

the axioms • Axiom 1, the independence axiom: Maintain the independence of the functional requirements • Axiom 2, the information axiom: Minimize the information content of the design

Where did AD come from? Nam P. Suh - MIT ME Department Chair - NSF Engineering Director - President of KAIST - Honorary doctorate from WPI in 1986 • Discovered the Axioms in the late 70 s at MIT – Looked for commonalities in good designs • Premise: good engineering design is based on – self-consistent axioms that – lead to the best solutions for all design problems. Keynote address from the 7 th International Conference on Axiomatic Design at WPI June 2013 (43 minutes) http: //www. youtube. com/watch? v=x. SI 8 Ux. Si 5 e. M

REFERENCES Recommended texts • Suh, N. P. , The Principles of Design, Oxford, 1990 • Suh, N. P. , Axiomatic Design: Advances and Applications, Oxford, 2001 • Suh, N. P. , Complexity: Theory and Applications, Oxford, 2005 4

Design is it Philosophy or Science? philosophy is what we call thought in its first, molten state, before it has had a chance to solidify into a scientific discipline Adam Kirsch, “Are We Really So Modern? ” New Yorker, Sept. 5, 2016 Are Suh’s axioms the solidification of the philosophy of design? Is engineering design a scientific discipline?

Commonality – The basis for scientific laws What was Newton thinking? Recognizing commonalities …

Origin of Axioms • Recognizing commonalities in what might seem to be disparate problems is a process of crystallization of ideas, i. e. , solidification. Is practicing design without axioms like solving mechanics problems before Newton?

Naturalness of Suh’s axioms • Conventional design prefers simplicity - KISS – keep it simple stupid • Axiomatic Design decomposes this simplicity directive into two parts – Axioms 1 & 2

Axiom one - Independence • Provides for adjustability and control • Avoids unintended consequences

Importance of adjustability - accommodate change CHANGE IS UBIQUITIOUS The universe is not in equilibrium • Something is always changing – Weather changes – People change – Needs change • Functions need to be adjusted Why is calculus so important? • because it models change • dy/dx describes how one thing changes with respect to another

Axiom 2 - Information • The more instructions that are required – The greater the chance that something is misinterpreted or forgotten • Equivalent to maximizing the probability of success achieving the FRs • Axiom 2 essentially encompasses Axiom 1 – Lack of controllability negatively impacts success

WHAT IS ENGINEERING DESIGN? • Scientists look at thing as they are and ask: why? • Engineers dream of things that never were and ask: why not? 12

Design is common to all kinds of engineering Engineers work with symbols the symbol is not the thing

The nature of engineering design • conceiving, planning, analyzing, comparing, and selecting components and systems – Building a consensus among the stakeholders • Functionally based and objective oriented. • Engineers create value by thinking …. and by communicating their thoughts 14

What is thought? “…thought is all about semantics” “Semantics is equivalent to capturing and exploiting the compact structure of the world. ” Eric Baum 2004 MIT press This compact structure is exploited through language and mathematics …symbols and their logical manipulation to solve problems 15

What are semantics? …meanings, relationships, argument structure, linking to syntax…integration of elements into a meaningful entity This suggests that we: 1. Develop an appropriate symbolic representation of design problems 2. Manipulate the symbols to achieve the best design solution 16

The nature of problems • Any problem can be cast as an engineering design problem • Axiomatic Design is the best way of solving engineering design problems • Axiomatic Design is the best way of solving all problems

Better, faster, and cheaper design solutions • • • Get all 3 with AD for designs and development Remove non-productive iterations Reduce complexity Provide metrics for progress and quality Communicate design intent Develop best design solutions

What is the method you use for your design process? • Has it changed? • Many engineering seniors cannot articulate any fundamental change in their method for design since high school – the differences are mostly in the analyses, • e. g. , stress and deformation • Many methods seem to consist of throwing ideas against a problem until something sticks – Lack good evaluation criteria

Design methods influence everything Nearly everything we use, are influenced by, see, touch or feel is designed

Design methods influence the cost and time of development • AD allows us to focus on the best design solution early in the process • Avoids non-productive iterations • Reduce time to market

Enhancing Innovation • Example: – Advantage of functional independence (axiom one) FR 1 FR 2 FR 3 DP 1 X 0 0 DP 2 0 X 0 DP 3 0 0 X

Axiom One Breakthrough Design Solution in Naval Warfare - March 1862 Monitor defeats Virginia American Civil War • Steam power makes locomotion independent from wind (decouples) • uncoupled design defeats greater size and fire power

CSS Virginia Former Merrimac: raised, clad with iron, fitted with steam, 12 guns

March 8, 1862 The CSS Virginia enters Hampton Roads and starts sinking conventional Union ships at will

USS Monitor Designer: John Ericsson Born July 31, 1803 Långbanshyttan, Värmland Died Occupation March 8, 1889 (aged 85) New York Engineer, innovator

USS Monitor versus CSS Virginia USS Monitor CSS Virginia/Monitor Length 173. 00 ft 262. 75 ft 1. 52 Beam 41. 33 ft 51. 16 ft 1. 24 Displacement 987 tons 3, 200 tons 3. 25 Crew 52 350 6. 73 Guns 2 12 6. 00

March 9, 1862 the USS Monitor arrives from New York and neutralizes the much larger, faster and more heavily armed CSS Virginia

New FR: Adjust direction of fire New DP: Swivel turret Fixed directions of fire THE CAPTAIN OF THE VIRGINIA ACCUSES THE CAPTAIN OF THE MONITOR OF NOT BEING A GENTLEMAN

Innovation by identifying coupling • A swivel turret decouples the direction of travel and the direction of fire (Monitor) • New FR – Adjust Direction of Fire Maintain the independence of the functional elements axiom one 21

FR-DP MATRIX Virginia FR 1 adjust direction of travel FR 2 adjust direction of fire DP 1 rudder X d e l p cou X Is this correct? Monitor DP 1 rudder DP 2 turret FR 1 adjust direction of travel X 0 FR 2 adjust direction of fire 0 X Corollary: each FR requires a DP 32

FR-DP MATRIX Virginia FR 1 adjust direction of travel FR 2 adjust direction of fire DP 1 rudder X d e l p cou X Monitor DP 1 rudder DP 2 turret FR 1 adjust direction of travel X 0 FR 2 adjust direction of fire X X Corollary: each FR requires a DP 33

AXIOM 2 - INFORMATION Maximize the probability of success • I = ln(1/p) where p is the probability of success • Reduce uncertainty – Minimize the possibilities of errors – Minimize the impact of wear, temperature and other variables • Promotes: Robust Design

SINGLE FR DESIGNS • Axiom one – “maintain the independence of the functions” is completely satisfied - since there is only one. • It is all about axiom two.

EXAMPLE: CLAMPING MECHANISM AND SPRING FR clamping force, F F linear spring k Design equation F=k. X close DP displacement, X (major-minor axis) 32

TRANSLATING TOLERANCES: FRS TO DPS softer spring, k 2 , results in a larger tolerance, and therefore lower information FR F F FR tolerance k 1 k 2 Breakage Slip X F=k DP tolerance X ΔX DP

STIFFNESS IN DESIGN • From axiom 2 → the lowest stiffness is best • Allows for – variance in manufacturing – wear – temperature change • Accommodates impacts

INFORMATION CONTENT • can be used for – improving yield in manufacturing, or – comparing delivery options – selecting springs in design …in the same design problem with the same units – all tied to the probability of success

DESIGNING A VACATION AXIOM ONE EXAMPLE FR 1 Relaxation FR 2 Romance Initial solution proposal DP 1 Ethanol DP 2 Dancing Ethanol Dancing Relaxation X 0 Romance X X Ethanol is not a good design solution - because it influences too many things. Yoga is more independent – think: flexibility, adaptability Preferable alternative DP 1 Yoga In the selection of the DPs: Maximize the independence of the functional elements… Yoga Dancing Relaxation X 0 Romance 0 X 36

Decomposition example • Good decomposition is essential to good problem solving • A good decomposition can make the solution obvious.

CENTERLESS GRINDING: EXAMPLE z G: Grinding Wheel - R: Regulating Wheel - B: Blade - W: Work piece 42

SITUATION - MEDICAL PART SUPPLIER Manufacturing a tube for arthroscopic surgery • The person left who had been feeding it by hand • No one else can feed it properly – the parts jam and the wheels have to be re-set • The part has a sharp end that people are afraind to handle • They are seriously behind of filling orders • Their engineers are imagining a multi axis robot simulating the hand motion to feed the parts – one month development 43

CEME APPROACH • Develop the minimum number of FRs that are Collectively Exhaustive and Mutually Exclusive 44

FUNCTIONAL REQUIREMENTS FR 1 align the part prior to insertion FR 2 maintain the alignment during insertion FR 3 protect the operator from the sharp end 45

SELECT DESIGN PARAMETERS FR 1 align the part in x and z prior to insertion 1. 1 align part within holder 1. 2 align holder with the machine FR 2 maintain the alignment in during insertion FR 3 protect the operator from the sharp end DP 1 mechanical part holder 1. 1 position of V in block 1. 2 bracket that goes between the V-block and machine DP 2 V-slot in an elongated block DP 3 push block 46

V-BLOCK part m DP 1 ec x lder o h t ar al p c i n a h y z DP 2 V slot, elongated V-block DP 3 push block 47

CLEAR STATEMENT OF FRs • Simplified the design • The device was in production by the end of the day – Development time reduced from weeks to minutes • Production bottleneck removed 48

Knowledge is power Axiomatic design is a powerful way to realize dreams of things that never were

First Canon of Engineering Ethics Hold paramount the safety, health and welfare of the public

Thank you very much for your kind attention! On the deck of the USS Monitor

ONLINE VIDEO RESOURCES FOR AXIOMATIC DESIGN • • • • • Prof. Chirstopher A. Brown Video books for purchase from Retrieve. com http: //myknowledgeapps. com/app/elements-of-axiomatic-design/ An Introduction to Axiomatic Design https: //www. youtube. com/watch? v=Wiimzx. RJh. Ws a workshop for pre-university educators Teaching Axiomatic Design: Part 1 - Introduction Teaching Axiomatic Design: Part 2 - Building Solutions Teaching Axiomatic Design: Part 3 - Axiomatic Design Teaching Axiomatic Design: Part 4 - Addressing Limitations Teaching Axiomatic Design: Part 5 - Customer Needs Teaching Axiomatic Design: Part 6 - Creating Value Teaching Axiomatic Design: Part 7 - The Axioms Teaching Axiomatic Design: Part 8 - Decomposition https: //www. youtube. com/watch? v=b. FIMa. Hr. J 8 No https: //www. youtube. com/watch? v=h. N 1 S 1 ba. Qyo 0 https: //www. youtube. com/watch? v=e. AGOGjpo. QRI https: //www. youtube. com/watch? v=Ze. Ce. Dad. Bqvs https: //www. youtube. com/watch? v=pd. Ir 5 x. JNKdc https: //www. youtube. com/watch? v=_Uo. WQBg-38 o https: //www. youtube. com/watch? v=Pw. HULkom. AU 0 https: //www. youtube. com/watch? v=r. OLSIWFj 54 c basic content for a first course in Axiomatic Design MFE 594 An Introduction to Axiomatic Design Part 1 MFE 594 An Introduction to Axiomatic Design Part 2 MFE 594 An Introduction to Axiomatic Design Part 3 MFE 594 An Introduction to Axiomatic Design Part 4 https: //www. youtube. com/watch? v=x. Ccys. LQ 0 d. Gk https: //www. youtube. com/watch? v=g. FGZz 3 Qt. VJ 8 https: //www. youtube. com/watch? v=0 mm 7 x_g. Jy. K 8 https: //www. youtube. com/watch? v=q. URM 1 A 1 BZJw • • Prof. Nam Suh ICAD 2013 Keynote with Nam Suh https: //www. youtube. com/watch? v=x. SI 8 Ux. Si 5 e. M • • • Prof. Dominik Matt Axiomatic Design for Sustainable and interdisciplinary building design https: //www. youtube. com/watch? v=_tw 2 DMAn. Sz. E • • • Prof. Aurelian Vadean Design Improvement of Hybrid Composite Joints by Axiomatic Design https: //www. youtube. com/watch? v=8 wz 6 Lsq. Gr 2 I