Design rational toolbox


Aerospace engineering design relies heavily on the use of past experience. It is known that engineering designers frequently need to revisit previous design solutions and understand the rationale for their generation. Design rationale is an explanation of why an artefact is designed the way it is, and not designed in any of the many other ways typically considered and rejected.

The Decision Rationale editor (DRed)

DRed allows designers to record their design rationale (DR) at the time of its generation and deliberation. The design rationale is displayed in a document as a graph of nodes linked with directed arcs. The user creates the nodes by choosing from a predefined set of element types. The key element types are: issue, answer, and argument.


The DRed software tool has been continuously developed since 2002, with support from Rolls-Royce plc, together with the UK EPSRC and Technology Strategy Board. It is owned and controlled by Rolls-Royce plc. Example projects created using DRed v3, and a history of public presentations related to DRed can be browsed here.

Download and install the toolbox

(this description assumes you have downloaded and installed CAM and are familiar with the general principles of creating models in CAM)

Installing Topic Maps: Since the Topic Maps toolbox is not part of the standard CAM distribution, it must be installed manually:

  1. Download the zipped Design rational toolbox files, and unzip to somewhere convenient (e.g. the desktop).
  2. Copy/move the "DRE" folder into the "palette" directory of your CAM installation.
  3. Restart CAM - you should now be able to create workbooks of type "DRE"
  4. Open or create a new workbook of type DRE

See also

More information

•    Aurisicchio, M., & Bracewell, R. H., (2013): Capturing an integrated design information space with a diagram-based approach. Journal of Engineering Design, 24(6), 397-428.
•    Wang, H., Johnson, A. L., & Bracewell, R. H. (2012). The retrieval of structured design rationale for the re-use of design knowledge with an integrated representation. Advanced Engineering Informatics, 26(2), 251-266.
•    Aurisicchio, M., Bracewell, R. H., & Wallace, K. M. (2010). Understanding how the information requests of aerospace engineering designers influence information-seeking behaviour. Journal of Engineering Design, 21(6), 707-730.
•    Bracewell, R. H., Wallace, K. M., Moss, M., & Knott, D. (2009). Capturing design rationale. Computer Aided Design, 41(3), 173-186.
•    Bracewell, R. H., & Wallace, K. M. (2003). A tool for capturing design rationale. In A. Folkeson, K. Gralen, M. Norell, & U. Sellgren (Eds.), Proceedings of the 14th International Conference on Engineering Design (ICED'03). Stockholm, Sweden: Design Society.