Concept Generation

A concept classification tree can be used to classify your group’s ideas. It is often a good tool to complement the structured brainstorming step, and the systematic process can help to highlight more ideas. Concept generation sits in the ideation phase, as it is a structured tool to explore every single opportunity or idea.

Example applications

Ulrich and Eppinger (see core resources) spend their chapter explaining the different ways that you could hammer a nail. Now, this sounds like an extremely trivial activity, but when explored fully becomes quite a powerful tool for organising thoughts and generating ideas. For example, when classifying

ideas to ‘store or accept energy’, they propose five ways (some are more feasible than others) to do this in a nail gun: chemical, pneumatic, hydraulic, electrical, and nuclear, with further sub-ideas under chemical and electrical.

Steps

As concept generation can go hand-in-hand with structured brainstorming, the approach described here assumes that you’ve completed structured brainstorming around a specific How Might We… question:

1. Group similar ideas as in step 5 of structured brainstorming
2. Look for common themes within or between the similar ideas. These themes will become the branches
3. Start to draw the concept classification tree. Start with the How Might We… question, and draw branches to the themes identified in step 2. If there are ideas that need to be broken down further, then create new branches until all ideas are exhausted.
4. Once all ideas are mapped, use the advice in Ulrich and Eppinger: prune less promising branches, identify independent approaches to the problem, expose inappropriate emphasis on certain branches, refine the problem decomposition on particular branches

Hints

• A single concept classification tree is useful, but to piece together a whole solution multiple classification trees are needed. Once you have explored the options around a number of different subsystems, you can easily piece these together, like in Exhibit 10 in the Ulrich and Eppinger reading (p.97)
• The classification tree is also a good way to break down ideas into functions and subsystem - a topic we’ll examine in the Logic & Function analysis and System Architecture topics.

Core resources

• Ulrich, K.T., and S.D. Eppinger, 1995. Product Design and Development. McGraw-Hill. Chapter 5 - Concept Generation [PDF, 25 pages]. This is the ultimate guide to using a systems engineering approach to generating ideas. In particular, see p.93 for the concept classification tree.