Design For Six SigmaProcess Workshop
By Ramon Balisnomo
ObjectivesProvide opportunity to walk the DFSS
– One example for the process T1 through T2b– Learn how to apply the DFSS methodology and
tools with a working exampleTeach the following tools and process steps
– Context Model– QFD and CTQ generation– Concept Generation
The OpportunityThe Department of Tourism along with City Developers have decided that they want to build an major landmark for the purpose of:
Generating more income for the City
Observation tower for tourist to visit
Prime real estate for shopping, restaurants, officesRelaying signals for televisions, radio, cell phones
The Finance Departed has budgeted $45000(k) for the total cost of this structure.
The City Planners want the structure to replace an existing clock tower a few miles from a municipal airport.
According to a survey of the local population, when asked what structure they admired the most – the number one response (over 50%) was the Eiffel Tower in Paris, France.
The ObjectiveBuild the tallest tower possible for the least amount of money
Tower’s Value Chain
Bldg. Development Committee
City Planning Committee
Municipal Org. Tourist
CityPopulation
Contractor
Budget Plan
Contract Control
City Plan
PrimaryDecision Maker
BudgetAuthorization
Tax Payers (Voters)
MOSTIMPORTANTCUSTOMER
Voice of the Customer (VOC)
Bldg. Development Committee
City Planning Committee
Municipal Org. Tourist
CityPopulation
Contractor
PrimaryDecision Maker
BudgetAuthorization
Tax Payers (Voters)
MOSTIMPORTANTCUSTOMER
•Airport•Transportation•Utilities, etc.
VOC
VOC
VOC
VOC
Bill
ContextKey Decision Maker’s Decision Criteria:1. Contract agreements: how well will the builder keep his/her promise? 2. Lowest cost wins; raw materials & time to build3. Less real estate (square inches) is better4. The safer (quality & reliability) the design appears, the better the design5. The builder will pay a penalty for not adhering to the contractMost Important Customer’s Success Criteria:1. Taller is better2. “I want to feel safe while I am there.”3. Unique feature; tourist attractionConstraints:1. The proposed site is located in the most expensive real estate in the City,
and the City will not demolish neighboring structures to make room for it. 2. Stability under windy conditions. The average wind speed is higher in this
City than the Country’s national average.3. Height versus close proximity to the airport. The proposed site is in the
direct path of the municipal airport’s main runway 4. The stability of the ground5. Access to parking, hotels, shops, restaurant, etc.
Voice-of-the-Customer Data: A Contextual Inquiry process generated the following observations:
Survey results showed that the tower has to be taller than the tallest existing structure to justify its cost
The tallest existing structure in the city is 24 stories* high The taller the tower, the higher the customer satisfaction level
The customer’s perspective on safety is dependent on several factors There’s a certified test for rating the stability of a structure Building swaying / movement it makes people feel unsafe Perceived visible / obvious safety features
Entertainment value Gift shop Observation deck Restaurant Thrill (e.g. glass floors, overhanging features, rotating floors)
Attraction A function of height, unique features, and entertainment value Lots of random data; team will use competitive analysis to evaluate further
*note: 1 inch = 12 feet
QFD: What’s Important to the Customer?
Unique Features 10 10 10
Dominates Skyline 8 8 8
Safety 9 2 7
Attractive Appearance 6 6 6
Accommodates existing structures
7 4 5
Low High
1 Unique Features
2 Dominates Skyline
3 Safety
4 Attractive Appearance
5 Accomodates Existing Structures
0.0 1.0 2.0 3.0 4.0
Simulation City Builidng Attraction ProjectSatisfaction Scores, Current ClocktowerTourist Attraction Success Elements
City Populace Tourists Proposed
Phase 1: Investing Money Before the Project Begins
You may invest up to $25K on voice-of-the-customer information by clicking on check-box next to the item(s) you want
Spending money will reduce your chances of winning; thus, you don’t have to buy anything
When you’re done, click on the brown command button entitled Invest the Money. Please note: you can’t go back and change your mind once you’ve made your selection
Team Exercise Roles & ResponsibilitiesProject Mgr / Team Leader
o Makes presentationso Facilitates discussion to make sure time constraints are
metFinance / Accountant
o Keeps track of material costs and timeo Operates the laptop computer
Reliability Engineero Validates that the design can pass environmental testo Operates the measuring tape (e.g. Height)
Construction / Assembly Manager (Optional)o Rebuilds the tower from scratcho CANNOT be the person who designed the tower
Phase 1: What Are You Buying for $25K? Voice of the Customer: Success criteria for choosing which tower will
win. This contains the mathematical formula for choosing the winning tower.
Quality Report on Tower Components: First-pass yield information (% Good) regarding the wooden & plastic parts.
Competitive Information: A look at the size and cost of towers made in the past. A good source of information if you are creatively challenged.
Verification Test: Minimum Reliability Requirements. Specifications on an environmental test the tower must pass.
Marketing Report: What’s the Demand for Towers? Specification on tower attributes customers want.
Manufacturing Process Requirements: Information on the cost versus the time it takes build a tower.
Phase 2: What the Kit Includes
102 pieces
Phase 2: Out-Bid Your Competitors
Look but Don’t Touch! Just by looking at the building pieces or components, estimate the: Number of components you’ll use (i.e., material
cost) The height of the tower you’ll build with the parts
you’ve estimated. The group with the Lowest Cost Per Inch will become the preferred tower
contractor. Click the Approve Bid button when you’re ready to submit your contract.
Phase 3: Develop Initial Tower Design Create a bill of materials by
entering the quantity next to each component.
The total cost should update automatically.
The maximum number of components (Max Qty) is in the far-right column.
Click the green button to approve the design.
Verification Test: Minimum Requirements
Before the design can go into production, it must pass the Golf Ball Test.
The Golf Ball must at least be 2 feet above the ground
The Golf Ball must not fall off despite the effect of the Cantilever
The Cantilever must support a minimum of 1 Washer.
You can adjust the position of the Ball & Cantilever to take advantage of the Tower’s most stable position.
Cantilever
Bungee Cord
Eye Bolt
Steel Washer
Golf Ball
Phase 4: Verify Tower Design Perform verification test. Make
adjustments to your tower until it passes verification test.
Re-enter you bills-of-material under the heading Adjusted Qty. If you’ve added more material, it will cost you twice as much at this phase.
Note the quality or percent yield of your tower. The higher the quality, the better your chances of winning
Do not approve design changes or freeze the design unless your tower has passed the minimum verification test.
Too High (unsafe) = 60 inches
Too Low (un-inspiring) = 36 inches
The ideal tower will be between 36 inches to 60 inches tall. Marketing analysis shows the product becomes significantly harder to sell (much less demand) when outside of these spec limits.
The height of the tower should fall within this range
Marketing Info: What’s the demand for towers?
Reliability Test: More Is Better
How many washers can you hang on the 18” Cantilever? More Washers = More Design Points
The test ends when the tower falls over or if a structure breaks off
The Golf Ball is NOT required for this test
You can adjust the position of the Cantilever to take advantage of the Tower’s most stable position.
Manufacturing Process Requirements
The project manager has budgeted 6 min. ± 2 min. for the assembly of the tower. If you finish before 4 minutes, there’s a 10% deduction from the cost of the tower due to efficiency. If you finish after 8 minutes, there’s a 15% penalty for going over the manufacturing budget (see Figure 1).
At 10 minutes, the clock is stopped. There will be a 25% penalty if the tower has not been completely assembled.
The assembly is finished when the Golf Ball does not roll off the tower within 5 seconds (see Figure 2). The Cantilever is not required.
The person who manufactures the tower cannot be the same person who designed the tower.
Figure 2Figure 1
4 min 8 min
10 min
-10%+15%
+25% Time
Freq.
Phase 5: Assemble & Verify Finished Tower
1. Measure the height of your tower
2. Measure the base width & length
3. Measure the height from the floor to the bottom of the eye-bolt in the test fixture
4. Take your tower completely apart after performing the “reliability test”
5. Pick a person other than “the designer” to assemble the tower back together. The assembly time won’t be complete until the golf ball is stationary on the tower
6. Record the time to the nearest minute and click the button Review Final Results
18” Cantilever
Bungee Cord
Eye Bolt
Steel WasherTOWER
Measure the height from the floor to the bottom of the eye-bolt in the test fixture
Step 3
How Customers Pick Which Tower To Buy
The tower with the best over-all score wins the competition.
The lower the score, the better the design
The overall score is calculated as follows:
Overall Score =
Cost Per Inch, CPI
Design Points, DP
Cost Per Inch (CPI)
Note: There are penalties for: Bad cost planning (budgeting) Not delivering on contractual agreements Design changes
Total Cost = Investment + Material (variable) + Manufacturing
+ Penalties
CPI = Total Cost / Height of the Tower
Design Points (DP)
DP = [ Height of Tower + Height Observation Deck
– Base Length x Base Width ] x Quality x Reliability2
Examples of Towers
Size Versus Cost
Tower α
Height = 49 inches
Base = 6 in. x 3.25 in.
Cost = $31,870
Tower β
Height = 63 inches
Base = 12 in. x 5 in.
Cost = $31,610
Tower δ
Height = 55 inches
Base = 8 in. x 5 in.
Cost = $27,610
Nicol-Sargent Tower: $18,400
Height= 57.5”Base=5”x11”