IENG 471 Facilities Planning IENG 471 - Lecture 15 Layout Planning – Systematic Layout Planning & Intro to Mathematical Layout Improvement 4/22/2017 IENG 471 Facilities Planning (c) 2005 D.H. Jensen

Warehousing Terms - Review SKU – Stock Keeping Unit Product in (packaged) form for warehouse operations. Value-Added A modification to the product to obtain business (a product enhancement from the customer’s perspective or an enhancement to the customer’s experience in getting the item). Cross-Docking Transforming incoming product to outgoing product without moving the product to production or storage. Slotting Selecting the location of SKUs in the storage zones. Goal is to optimize (reduce) pick times across all SKUs within a zone. Forward Pick Area An area housing fast-moving/frequently-picked items between the shipping and storage areas for quick order fulfillment. 4/22/2017 IENG 471 Facilities Planning

Layout Alternatives - Strategies Fixed Position Layout (Difficult-to-move Products) Process Layout (Job Shop) Product Layout (Mass Production Line) Group Technology Layout (Product Family) 4/22/2017 IENG 471 Facilities Planning

Layout Alternatives: Fixed Pos. 4/22/2017 IENG 471 Facilities Planning

Layout Alternatives: Process 4/22/2017 IENG 471 Facilities Planning

Layout Alternatives: Product 4/22/2017 IENG 471 Facilities Planning

Layout Alternatives: GT / Family 4/22/2017 IENG 471 Facilities Planning

How to get from data to design? Product, Process & Schedule Data: BOM Routing/Assembly Chrt Operations Process Chart Precedence Diagram Scrap/Reject Rates Equipment Fractions Material Handling Unit Loads Storage Systems Efficiencies Transportation Systems Flow, Activity & Space Data: Group Technology From – To Chart Relationship Chart Dept Footprint & Aisle Space Personnel Space Parking Lot Restroom/Locker room Food Prep/Cafeteria ADA Compliance Order Data Profile Multiple Analysis Profiles 4/22/2017 IENG 471 Facilities Planning

Muther: Systematic Layout Plan SLP Benefit is methodical consideration of issues Can work the process manually or with computer aides “Roadmap” for the process is good for communication Adds the following stages: Analysis Search Evaluation Engineering Design Process! 4/22/2017 IENG 471 Facilities Planning

IENG 471 Facilities Planning In-Class Example Recognize Need Generate scenario Collect Data What info Analyze Data Combine Flow & Relationship  Affinity Diagram Generate Design Expand Affinity Diagram to encompass work space Multiple Designs! Evaluate Criteria Needed! 4/22/2017 IENG 471 Facilities Planning

Relationship Chart - Qualitative 4/22/2017 IENG 471 Facilities Planning

Converting Closeness to Affinity 4/22/2017 IENG 471 Facilities Planning

IENG 471 Facilities Planning From – To Chart Example 4/22/2017 IENG 471 Facilities Planning

IENG 471 Facilities Planning From – To Chart to Flow Review: flow volume in chart Above diagonal is forward flow Below diagonal is back-track flow Combine both flows to represent volume of interactions, then Pareto! Qualitative Flow Quantitative Flow 4/22/2017 IENG 471 Facilities Planning

Converting Quantitative Flow to Affinity 4/22/2017 IENG 471 Facilities Planning

Converting Both to Final Affinity 4/22/2017 IENG 471 Facilities Planning

Review: Conversion Steps Convert Flows to Affinities Qualitative converts directly to A E I O U X Quantitative converts to A E I O U X via Pareto analysis of flow volume Combine Flow Affinities Numerically A = 4, E = 3, I = 2, O = 1, U = 0, X = negative value Quantitative flow may be multiplied by a weighting factor Sum Quantitative & Qualitative Convert to Final Affinities Pareto analysis of numeric affinities to get A E I O U X Add: Check Final Affinities for Political Correctness Communication feedback to involved parties 4/22/2017 IENG 471 Facilities Planning

Converting Flow to Affinity Strength of relationship is shown graphically Number of lines similar to rubber bands holding depts together Spring symbol to push X relations apart 4/22/2017 IENG 471 Facilities Planning

Converting Flow to Affinity 4/22/2017 IENG 471 Facilities Planning

Converting Flow to Affinity Lay the Affinity Diagram over a site plan to get better idea of layout 4/22/2017 IENG 471 Facilities Planning

Improvement: Size of Departments Some experts suggest modification: Use circles instead of flow symbols Scale circles to equate with the estimated size of the departments Use rectangular, sized blocks instead of circles – improves input to computer layout methods Computer packages are still being developed … 4/22/2017 IENG 471 Facilities Planning

Layout Models – Mathematical Objective Functions Mathematical models can be constructed to measure a design, and help to quantify when it has been improved Like many mathematical models of physical systems, part of the “art” is knowing what assumptions are made in a model, and when these assumptions are “reasonably met” The “best” models are not always the most complex – in fact many “comprehensive” mathematical models become intractable or take too long for computation when scaled up to a “realistically–sized” problem Frequently, meeting the data collection (and verification) requirements for many mathematical problems is very difficult However, as the cost of automated data collection and storage drops, and has computational power increases (hardware speeds and parallel programming techniques improve), both mathematical models and simulations become more attractive – more tools for the toolbox! 4/22/2017 IENG 471 Facilities Planning

Layout Models – Mathematical Objective Functions Assume we have these variables defined for n departments: i is an index to the “FROM” department in a pair of departments j is an index to the “TO” department in a related pair Thus i and j could be the row/column indices for a From/To Chart fij is the unit load FLOW from the i th to the j th department Thus fij is the cell entry in the From/To Chart (matrix) cij is the COST to transport a unit load from the i th to the j th dept dij is the travel DISTANCE from the i th to the j th department aij is the ADJACENCY of the i th and j th department pair, which is defined to be: 1 if the i th and j th departments share a common edge (border) – or 0 if the departments have no common edge or only touch at a point 4/22/2017 IENG 471 Facilities Planning

Layout Models – Mathematical Objective Functions Minimize the transportation cost: Maximize the flow-weighted adjacency of departments: Evaluate flow weighted layout efficiency (relative measure): 4/22/2017 IENG 471 Facilities Planning

Example – Mathematical Objective Function Assume the From/To matrix (below) … and the department layout(s) (below): then the Flow-Weighted Adjacency score(s) would be: 200(1)+250(1)+300(1)+500(1)–20(1)+350(0)+10(1)+175(1)+100(0) = 1415 200(1)+250(1)+300(1)+500(1)–20(0)+350(0)+10(1)+175(1)+100(0) = 1435 200(1)+250(0)+300(1)+500(1)–20(0)+350(1)+10(0)+175(1)+100(1) = 1625 4/22/2017 IENG 471 Facilities Planning

Criticisms and Resources Frequently, improvements in the simpler mathematical objective functions result in long, “snake-y” department shapes Not always physically possible Adjusting the objective function to penalize snake-y results in more complex objective functions Data representations become more complex, too – and can increase computation time disproportionately The simple, transportation cost function assumes we move from/to the center “point” of the departments Isn’t really accurate for real departments (especially large sized) Becomes even less true when the departments get more snake-y Text Chapter 10 presents more mathematical models–try some! MIL Lab computers have some software available The software tends to be research prototypes, but can be fun to try! 4/22/2017 IENG 471 Facilities Planning

IENG 471 Facilities Planning Questions & Issues Class time is for project (after Exam II) Review & HW solutions TODAY. Exam II scheduled for 07 NOV. 4/22/2017 IENG 471 Facilities Planning