A PROPOSAL FOR A CO-DESIGN METHOD IN CONTROL-SYSTEMS USING COMBINATION OF MODELS

In this paper we propose a co-design method for control systems using combination of models. By ''codesign,'' we mean a cooperative design m ethod in which the behavior of the entire system is simulated as a sin gle model while parameters of the system are being optimized. Our co-d esign method enables the various subsystems in the system, which have been designed independently as tasks assigned to different designers i n the traditional design method, to be designed simultaneously in a un ified cooperative way from the system-wide perspective of a system des igner. Our proposed method combines models of controlling and controll ed subsystems into a single model for the behavior of the entire contr ol system. After the optimum control conditions are determined through simulation of the combined models, based on the corresponding algorit hms and parameters, ASIC design proceeds quickly with accurate verific ation using iterative replacements of the behavior model by the electr onic circuit model. To evaluate the proposed method, we implemented a design environment. We then applied our method to the design of ASICs in three test cases (in a control system and in audio-visual systems) to investigate its effectiveness. This paper introduces the concepts o f the proposed co-design method, the design environment and the experi mental results, and points out the new issues for system design.