A Data-Base Management Scheme for Computer-Aided Control Engineering

There has been substantial progress made in the past decade in the development of analysis and design software for computer-aided control engineering (CACE). Engineering data-base management (EDBM) for support of CACE has not received much attention until recently, however. As CACE environments become more comprehensive and more powerful, the need for keeping track of the models, simulations, analysis results, control system designs, and validation study results over the control system design cycle becomes more pressing and the lack of EDBM support becomes more of an impediment to effective controls engineering. We have defined and implemented a CACE environment with EDBM as an integral part. The data base is organized in a hierarchical famework having the levels Project, Sub-project, Model, Attribute, and Element. The levels Project and Sub-project accommodate several control engineers working on a single project, with a project lead engineer having responsibility and control of the entire data base. Within a project, Models (plant models, control system models, etc.) are the main focus. Each model has two attributes, a Description and a Result_set. Fundamental properties plus component models (representations of a plant, compensator, sensor, etc.) comprise the elements of a Description; elements of a Result_set include any data generated with the model, such as a time-history, frequency response, etc. One factor that complicates the CACE DBM problem is that system models used for simulation, analysis, and design activity usually evolve as a project progresses.