Design space exploration
Eliciting and analyzing conceptual designs
In a project with collaborators from the Systems Engineering Design (SED) group in Sweden and the University of Auckland, we set out to explore conceptual design spaces in a systematic and quantitative manner to narrow them down to a handful of feasible and valuable concepts for further development and detailed design. We pose the question:
How can we analyze conceptual designs and quantify their ability to absorb a change in design requirements?
To answer this question, we borrowed concepts from design margins because of their ability to act as a buffer against change in design requirements
We used the example of an aeroengine component to demonstrate our proposed concept synthesis and analysis method. We enumerated four concepts by combining the available vane cross-sections with the lean configuration of the struts shown below. Design margins are present in each concept due to the discrete nature of each concept’s available means (e.g., choices for vanes and lean angles). The more margin is present, the more change can be absorbed but the worse is the performance of the strut (e.g, the weight and manufacturing costs of the strut). These effects are described by Change Absorption Capability (CAC) and Impact on Performance (IoP), respectively.
We use a library which implements the margin value method
The most valuable design is the one that corresponds to the red line in the PCP and red dot on the scatter plot. It is trivial to analyze and choose the most suitable design(s) when our selection is limited to just four concepts. However, our method is most useful when the number of combinations grows large. We demonstrate this on an example with 6,552 concepts shown below. Using the PCP, or the scatter plot, the designer can pinch and narrow their selection down to a few candidates.