M.Sc Thesis

M.Sc StudentAlexander Shihmanter
SubjectCapturing the Conceptual Design Process with
Concept-Configuration-Evaluation Triplets
DepartmentDepartment of Aerospace Engineering
Supervisor Dr. Kroll Ehud
Full Thesis textFull thesis text - English Version


Design knowledge is diffused throughout the organization via the minds of the design team, in reports and documentation, in sketches, in CAD drawings, and in the artifact itself. Some projects fail to leave proper design documentation behind them. The problem of capturing conceptual design data is addressed by the current research.

The research investigates the suitability of using sequences of concept-configuration-evaluation triplets to capture the conceptual design rationale and process. The sequence of concept-configuration-evaluation triplets is derived from the Parameter Analysis methodology for conceptual design, which is based on the realization that human design thinking takes place at two different levels, called concept space and configuration space. Concept space contains the ideas or concepts that provide the basis for the elements of configuration space. Configuration space is the place that holds the outputs and physical objects (or their representation) of the process. Every idea created in concept space is converted to hardware implementation in configuration space. Movement from one point to another in configuration space is possible only be visiting concept space. Evaluation is an intermediate step applied to the configuration in order to examine whether any changes are needed, and if so, another move to concept space is initiated.

The three repeated steps for capturing the design rationale are therefore defined as:

1.      Concept - finding and defining the idea or reason for the next step.

2.      Configuration - devising a configuration to realize or implement the idea from the previous step in hardware representation.

3.      Evaluation - critical examination of the most recent configuration in light of its ability to realize the idea and satisfy the design requirements.

The research shows the suitability of the proposed method with a number of case studies. Each case study provides an example of capturing the design process with the proposed methodology; the difference between the case studies is the conceptual design method used for the original example.

In addition, C-K theory is reviewed to further understand the subject of capturing design rationale. C-K theory is the first to explicitly express the knowledge used during the design process as a new space, the K (knowledge) space. The current research attempts to highlight the differences in design rationale capture between the concept-configuration-evaluation method and C-K theory, and study how the theories can complement each other. The possibility of extending the triplets methodology with the notion of knowledge space is shown.