In part 1 and part 2 of this series we have been looking at how physical conflict in design drive up product cost and how the separation principles of TRIZ methodology help us to side step those conflicts.
So far we have looked at three of the five separation principles:
- Separation in Time
- Separation in Space (Location)
- Separation in Space (Axis)
Today we’ll look at two more…
Separation in Scale
The fourth question to ask when you find a physical conflict in your design is, “can I assign one side of the conflict to the ‘whole’ and the other side to the ‘parts’.
For example If I’m an architect designing a sky scraper, I’m confronted by the conflict:
- Building must be rigid (for user comfort)
- Building must be flexible ( to withstand seismic and wind events)
Using separation in scale you realize that the rooms need to be rigid but the building as a whole can be flexible. By designing the building so that the floors hang from the outer shell of the building the conflict can be resolved.
Another clever use of separation in scale is in the design of body armor. High end body armor needs to be rigid to withstand high power rounds but flexible to allow user agility. Dragon Skin assigns the “rigid” requirement to ceramic scales and the “flexible” requirement to the system as a whole. Check out the Dragon Skin Video.
Separation on Condition
The final separation principle we will discuss is closely related to separation in time. I’ve broken it out because I’ve found that treating it as a separate principle often leads us to look outside the system proper – another TRIZ technique.
The question to ask here is, “Do the two sides of the conflict occur under different conditions”. If they occur under different conditions, it may be possible to borrow resources from the conditions themselves to solve the problem.
The bimetallic strip in an old school thermostat is a great example – it uses the change in temperature (conditions) to actuate the switch contacts.