APPLICATION OF QUALITATIVE REASONING IN ENGINEERING

Qualitative reasoning is an alternative problem-solving technique usef ul for the conceptual design of structures. Qualitative reasoning repr esents the relationships between parameters in a model, and a search c omputation assigns values represented by intervals and relevant points in the behavior: The traditional difference between analysis and desi gn or input and output parameters in a procedural computation is not e xistent in qualitative reasoning, since all the parameters in a model are equally represented. Qualitative reasoning derives values for para meters even with incomplete and imprecise knowledge about the model. T his work presents a qualitative structural analysis framework, suitabl e for the evaluation of conceptual designs as well as for tutoring sys tems. The framework has been implemented in a computer program called Agrippa using the computer language Prolog. Based on a representation of fundamental principles of equilibrium, compatibility and force-defo rmation and all incomplete knowledge of geometry and topology Agrippa derives the signs and relative magnitude of forces and displacements f or three-dimensional models of structures.