Sample DOE's

OptiMal by the Taguchi Methodology is the most effective and cheapest way to optimize complex problems being influenced by many factors simultaneously. The Method ensures that you avoid the primitive an ineffective one at a time approach.

The design of experiments can be used in almost any industrial branch.

Some of examples are part of the demonstrations included with the program.

1. Chemical, pilot plant examination. L8A model

  • Catalyst
  • Concentration
  • Temperature

The response is measured as the yield of the process.
Strategy: The larger the better.

2. Car experiment. L4 model
Find the car reaching 0-400 yards before the other.

  • Car
  • Driver
  • Tires.

Strategy: The smaller the better.

3. Heat seal assembly. L9 design.

  • Temperature
  • Pressure
  • Holding time.

Strategy: The bigger the better

4. Plastic foundry. L18A design Xerox.

  • Inlet pressure
  • Cycle time
  • Temperature of the form
  • Melting temperature
  • Counter pressure
  • Cooling time
  • Settling time.
    Strategy: Nominal is best.


5. Clutch performance in the car industry. L9 design.

  • Compression
  • Angle error
  • Linear error
  • Supplier

Strategy: The larger the better.

6. Speedometer cable. Quinlan. L16A design.

  • Kappe ydre diameter
  • Kappe pressestempel
  • Kappe materiale
  • Kappe fremføringshastighed
  • Skærmtråd type
  • Skærmtråd spænding
  • Tråd diameter
  • Kappe spænding
  • Kappe temperatur
  • Yderkappe materiale
  • Yderkappe stempel type
  • Smelte temperatur
  • Skærm pakning
  • Kølemetode
  • Fremføringshastighed

Response: Shrinkage of the cable.
Strategy: The smaller the better.

7. Pizza production, recipe, L18A design.

  • Temperature
  • Pressure
  • Baking time
  • Mixing time
  • Number of revolutions of the mix

Response: The best yield (taste is the measure),
Strategy: The bigger the better.

8. Nuclear power plant, material refinement, Design: L16A

  • Water/Cement ratio
  • PFA/OPC ratio
  • Water temperature (C)
  • Powder feed rate (Kg/min)
  • Powder addition Sequence
  • Mixing time
  • Paddle speed (rpm)
  • Grout recirculation rate (L/min)

Response: Grout fluidity, Strategy: The bigger the better.

9. Automobile driven plate and "Torsional Hysteresis". An engineering problem.

  • Dimensional characteristics
  • Flatness
  • Squareness
  • Surface condition
  • Frictional characteristics
  • Environmental characteristics

Response: Reduction of variability, Strategy: Nominal is best.
A reduction of 50% of the variability was achieved at Automotive Products PLC.
L16A design.
Factors or characteristics:

10. Automotive brakes, foundry optimization at Ford Leamington, Design: L12.

  • Catalyst age
  • Pins/Bushings
  • Blow head
  • Cope temperature
  • Cure time
  • Mixing method
  • Blow pressure
  • Blow chamber level
  • Core box cleanliness
  • Spray mount

Response: Scabbing. The scrap factor was drastically reduced below 0,5%. The brakes are of the types with internal ribs to force cooled air to the plates.

11. Automotive seam welding Ford. L16A design.

  • Weld time
  • Cool time
  • Weld current
  • Cradle speed
  • Wheel condition
  • Air pressure

Response: Tensile strength; Strategy: The bigger the better.

12. Plastic moulding of buttons for a telephone at Bang & Olufsen a/s. L16 A design.

  • Cycle time
  • Inlet temperature
  • Cooling time
  • Cooling temperature in the form, front part
  • Rear part
  • Counterpressure

Response: Two: Surface quality and nominal diameter; Strategy: The smaller the better and Nominal is best.

13. Plastic cover for a gramophones. At Bang & Olufsen. Design L8A.

  • Temperature
  • Preheating
  • Cooling time

Response: Nominal size; Strategy: Nominal is best.

14. Optimization of the soldering process of printed circuit boards. L36 design.

  • Conveyor speed
  • Preheating above
  • Preheating under
  • Solder wave angle
  • Pump speed
  • solder paste flow
  • and many more


15. Optimization of an aluminum foundry process at JAI.

16. Welding rivets to aluminum process at Mekoprint.

17. Coating plastic parts at Bang & Olufsen.

18. Printed wiring board Optimization of the lamination process at Bull.

19. Tile manufacturing process. Reduction of the noise from the spread in the temperature from tiles placed in the middle and at the outer limits. L8 Design.

20. SMD assembly line process, Kirk Electric. L12 design.

  • Sucking force
  • pressure of pickup 1
  • Pressure of pick-up 2
  • counterpressure
  • Glue pressure

Response: Placement accuracy; Strategy: the smaller the better.

21. Zink coating of nails at NKT. L27A design.

  • Concentration of the zink
  • Sodiumhydroxide
  • Sodium cyanide
  • Sodium carbonate
  • revolutions (rpm)
  • Current (Amps)

Response: coating size; Strategy: The bigger the better.

22. Thick film printing at Hytek. L16 design.

  • Emulsion
  • snap-off
  • printing speed
  • Rakler speed
  • Rakler pressure


Bicycle Experiment
In experiment number 1 the student, Norman Miller, using a factorial design with all points replicated, studied the effects of three variables-seat height (26, 30 inches), light generator (on or off), and tire pressure (40, 55 psi)-on two responses-time required to ride his bicycle over a particular course and his pulse rate at the finish of each run (pulse rate at the start was virtually constant).
To him the most surprising result was how much he was slowed down by having the generator on.
The average time for each run was approximately 50 seconds.
He discovered that raising the seat reduced the time by about 10 seconds, having the generator on increased it by about one-third that amount and inflating the tires to 55 psi reduced the time by about the same amount that the generator increased it. He planned further experiments.