| Configuration design is a type of design activity in which a set of pre-defined components are combined in certain ways to construct a system. A general framework for automated configuration design is developed in this dissertation.;In the proposed framework, design specifications are separated into functional requirements, performance goals, and constraints. Starting with functional requirements, a skeletal design comprising of essential functions is created. The functions in the skeletal scheme are then either mapped to physical devices to satisfy performance goals and constraints or decomposed into simpler sub-functions. The process of mapping functions to physical devices is thus interleaved with the function-decomposition process. The level at which a function is mapped to a physical device is directly related to the stringency of performance goals and constraints. Fundamental issues concerning the configuration design process such as function-sharing, granularity of design building blocks, and combinatorial explosion, are also addressed.;Based on the proposed framework, a prototype knowledge-based design tool called HYSYN (HYdraulics SYNthesizer) that automatically configures hydraulic systems was developed. Starting with design specifications, HYSYN identifies essential functions, constructs a functional configuration, performs quantitative inferences, and specifies appropriate catalog components and their interconnections. HYSYN's knowledge base contains a few domain-independent functions and a number of hydraulic catalog components and algorithms. Domain-independent algorithms have been developed for synthesizing a scheme of functions for power routing, sequence scheduling, and signal feedback looping. Domain-specific algorithms for catalog component selection have also been implemented. The HYSYN program is written in Common Lisp Object System and has been tested for configuration of hydraulic sequencing and synchronizing circuits with multiple inputs/outputs.;Although, the hydraulics domain investigated here is more modular than general mechanical systems, it is less modular than electronic circuits. The hydraulics domain thus serves as a middle ground between electronics and mechanical domains and is used as a testbed for this research in configuration design. In spite of its modularity, automated configuration of complex hydraulic circuits is by no means trivial. The methodology underlying the configuration design process can also be extended to other application domains as well such as general power transmission systems design. |
