39 Engineering Parameters

from http://www-personal.engin.umich.edu/~gmazur/triz/

Altshuller extracted from over 1,500,000 world-wide patents these 39 standard technical characteristics that cause conflict. These are called the 39 Engineering Parameters shown in Table 2. Find the contradicting engineering principles. First find the principle that needs to be changed. Then find the principle that is an undesirable secondary effect. State the standard technical conflict.

Example. The standard engineering parameter that has to be changed to make the can wall thinner is "#4, length of a nonmoving object." In TRIZ, these standard engineering principles can be quite general. Here, "length" can refer to any linear dimension such as length, width, height, diameter, etc. If we make the can wall thinner, stacking-load weight will decrease. The standard engineering parameter that is in conflict is "#11, stress."

The standard technical conflict is: the more we improve the standard engineering parameter "length of a nonmoving object," the more the standard engineering parameter "stress" becomes worse.


Table 2. The 39 Engineering Parameters

  1. Weight of moving object
  2. Weight of nonmoving object
  3. Length of moving object
  4. Length of nonmoving object
  5. Area of moving object
  6. Area of nonmoving object
  7. Volume of moving object
  8. Volume of nonmoving object
  9. Speed
  10. Force
  11. Tension, pressure
  12. Shape
  13. Stability of object
  14. Strength
  15. Durability of moving object
  16. Durability of nonmoving object
  17. Temperature
  18. Brightness
  19. Energy spent by moving object
  20. Energy spent by nonmoving object
  21. Power
  22. Waste of energy
  23. Waste of substance
  24. Loss of information
  25. Waste of time
  26. Amount of substance
  27. Reliability
  28. Accuracy of measurement
  29. Accuracy of manufacturing
  30. Harmful factors acting on object
  31. Harmful side effects
  32. Manufacturability
  33. Convenience of use
  34. Repairability
  35. Adaptability
  36. Complexity of device
  37. Complexity of control
  38. Level of automation
  39. Productivity