History of Agility. Outline WHAT IS "AGILE MANUFACTURING" Characteristics of Agile Manufacturing DESIGN FOR AGILITY

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1 1 DESIGN FOR AGILITY Outline Andrew Kusiak 19 Seamans Center Iowa City, Iowa $ The concept of agile manufacturing Design for agility rules Design for reconfigurability Tel: Fax: andrew-kusiak@uiowaedu Agility: The measure of a manufacture's ability to react fast to sudden, unpredictable change in customers demand for its products and services and make a profit (Noaker 199) WHAT IS "AGILE MANUFACTURING"? The real issue in agility is reconfiguration, ie, the ability to assemble the resources needed quickly (Industrial Week 199) In an 'agile' enterprise, products will be built quickly and cheaplyfor a customer based on detailed date received at the point of sale (Brooke 199) Characteristics of Agile Manufacturing 1 Greater product customization - product variety at low unit cost Quick response to changing market requirements Upgradable products - designed for modularity, disassembly, recyclability, and reconfigurability Dynamic reconfiguration of processes and systems - to accommodate swift changes in product designs or the introduction of new products History of Agility Flexible Integrated JIT Lean Agile e-manufacturing

2 Agility and e-service Marketplace Parallel concepts Enterprise Agility - operations perspective Enterprise n Internet Enterprise e-business - information processing perspective Enterprise 1 Manufacturing Provider Design Information Hub Delivery Provider n Internet Provider Supply Provider 1 Rule 1 Modular System Design Design for Agility Rules Decompose a complex system into several independent units

3 Minimize st TSP Formulation N N cijx ij i=1j=1 N x ij = 1, j = 1,, N i=1 N xij = 1, i = 1,, N j=1 Before decomposition Relax subtour constraint After decomposition System 1 System System K ij ui - u j Nx ij N - 1, i =,, N, x ij j =,,N, i j = 0, 1, i, j = 1,, N u 0, i = 1,, N Assignment problem Example Cost matrix [ Cij] Each product processed on two subsystems {P5, P7, P6, P10, P1, P9, P8, P, P, P, P5} COST: 180 {P1, P7, P6, P10, P8, P9, P1} COST: 1 {P5, P, P, P, P5} Gain Total setup reduction (1 vs 180) Makespan reduction {P1, P7, P6, P10, P8, P9, P1} {P5, P, P, P, P5} Two subsystem schedule vs sequential one (Cyclic schedule) Any Magic? No precedence constraints Each subsystem has to be able to perform the operations assigned The reduced cost is due to relaxation of the cycle elimination constraint

4 Rule Robust Product Design Design Goal Design a product with robust scheduling characteristics Minimize the impact of disruptions on a production schedule due to changes in the product mix and production demand Products with a Special Structure- Two Machine Model Example Electronic assembly Mechanical assembly Top cover 5 Card Plug for power cord P: Snaps Slots for snaps Product family with a linear assembly structure Old system 5 Changes in Product Mix Do Not Affect the Production Schedule P: Old design 5 S Old schedule {P, P, P1} {P, P, P1} {P, P1} Planned schedule Production of P is cancelled Actual schedule P1': P': P': New design Same character schedule Similar system layout New system S New schedule {P', P', P1'}

5 5 Example 1 1 Rule Streamlining the Flow of Products Streamlined system P: Non-streamlined system S S S Flow shop type flow Job shop type flow Example (cont) Streamlined system Non-streamlined system Rule Design Short Assembly Lines S Johnson's algorithm: Makespan= 0 S S Heuristic rule: Makespan= 58 Reduce the number of stations in an assembly line Problems with Long Assembly Lines Example (1) Difficult to balance () Behavioral problems () NP-completeness of the scheduling problem Three station system Difficult scheduling P: 5 6 S S 5 Easier scheduling 5 6 S Two station system

6 6 Example (cont) Short system Long system Rule 6 Simplify the flow of products S S S Johnson's algorithm: Makespan = 8 S Heuristic scheduling rule: Makespan = 7 Design products to simplify the flow of products in a multi-product assembly system Five Types of Product Flows Cycles ----> Backtracking Repeat Serial By-pass P: Backtracking Branch/Merge Superimposed graph Assign operations to stations Eliminate Cycles by Redesign Early (Machining-Driven) Product Differentiation Strategy P: New System Design Parts Parts Assemblies Redesign Assign operations to stations P1 P P1 P A1 P : Superimposed P P Machining P P A Assembly

7 7 Delayed (Assembly-Driven) Product Differentiation P5 P6 P7 P5 P6 A P A1 P8 P9 A P8 P9 P10 P11 Machining P10 P11 A5 Assembly A