ABSTRACT
In the late 1980s, we developed one of the early CBD systems called Kritik. Kritik autonomously generated preliminary (conceptual, qualitative) designs for physical devices by retrieving and adapting past designs stored in its case memory. Each case in the system had an associated SBF device model that explained how the structure of the device accomplished its functions. These case-specific device models guided the process of modifying a past design to meet the functional specification of a new design problem. The device models also enabled verification of the design modifications. Kritik2 is a new and more complete implementation of Kritik. In this chapter, we take a retrospective view on Kritik. In earlier publications we had described Kritik as integrating CBR and MBR. In this integration, Kritik also grounds the computational process of CBR in the SBF content theory of device comprehension. The SBF models not only provide methods for many specific tasks in CBD, such as design adaptation and verification, but they also provide the vocabulary for the whole process of CBD, from retrieval of old cases to storage of new ones. This grounding, we believe, is essential for building well-constrained theories of CBD.
