SUMMARY

SUMMARY

“THE ROLE OF THERBLIGS IN AUTOMATED DESIGN PROCESS MAPPING”

Hemanth Kumar V (36)

The research presented in this paper involves the detailed analysis of a user's actions whilst carrying out a design activity in a virtual reality (VR) environment. It is proposed that the analysis can be used to extract the design knowledge that is generated during the design session.

When a designer completes a design in a computer-aided design (CAD) environment, the end result contains only the solution to the design problem, but none of the design knowledge that is created, or learned, during the session. This means that the reasons the designer came up with the final solution will not be known to other users, unless that information was explicitly stated by the designer, either during the design session or afterwards. However, having to record this extra information will not only take more time and effort, but it will also disrupt the design process and creativity of the user. Therefore, it is proposed that if each individual action of the user during the design session could be logged and analysed, it would give the potential for formalising the design rationale of the designer. Rationale, in this case, refers to the user’s reasons for making their design decisions during the session. Since the logging is carried out unobtrusively and automatically in the background, the designer will not be disrupted and no extra work will be required from them to record their design actions. After obtaining the formalised design rationale, it could then be used to aid subsequent users, who are carrying out a similar design task, by providing hints to them as well as identifying any mistakes that they have made.

 Two analysis methods, called therbligs and chronocyclegraphs, have been applied to study a user’s motion when carrying out a design task in the virtual 16 of 18 environment, to gain a detailed understanding of the user interactions and process activities. Both methods have allowed any inefficiency in the user’s motion, processes and VR interface design to be visually identified and analysed. One potential application of the data obtained from the analysis is the extraction of ‘thinking time’ by searching for pauses in the user’s activity or changes in their behaviour. This may

highlight areas where the user is thinking about the design, and may imply design intent, or reasoning, from the actions leading up to, and after, an event where a design decision has been made.