Interactive graphics for the computer-aided design of dynamic systems

This paper addresses the general approach to the problem of designing an interactive environment through which graphical descriptions of dynamic systems, such as block diagrams and signal flow graphs, may be input, manipulated, transformed, renumbered, and output at a modern graphics workstation. It is shown that a data-base environment, in conjunction with an icon-driven user interface, is an efficient method for defining and editing system descriptions. Several transformation, layout, and renumbering algorithms are discussed. The use of symbolic computation for the efficient preprocessing of algebraic data for numerical design packages is also discussed.