Managing knowledge navigation in design with mixed-initiative dialogue

In generative design systems, the interaction between the designer and the generative formalism is typically transactional. The system responds to a single query or utterance with one or more results, which when sent back to the user define the transaction. A neat conceptual separation exists between user tasks and system tasks, rendering the modelling of joint responsibility for generation difficult. A mixed-initiative model of interaction is necessary to support forms of dialogue where both the designer and the formalism may share responsibility over the same task. Mixed-initiative provides a robust basis for combining design interaction with automated or intelligent systems. In such systems, the role of both user and formalism are integrated into an incremental-based model, where the user and the formalism can share and input data through a common shared resource, on a common shared task. Generative design systems provide formal representations that aid designers in exploring spaces of designs. We develop a formal representation of design spaces and unification-based algorithms for generation in the specification and implementation of design space explorers , computer programs for constructing, navigating and exploring spaces of design problems using feature structure theory. They adopt the unification view of incremental generation and provide a representation for the constraints on a design space, relate those constraints to the generation of partial designs and supports intermediate representations of design states. Extending this work with exploration systems, we report on the development of a graphical notation to support mixed-initiative dialogue in generative design systems. We demonstrate the use of this notation in design space exploration and discuss its implications for interaction with generative design systems.