Visualisation tools for 2-D system design

Graphical procedures have been used within control system design for over two decades. In classical linear systems theory, frequency domain representations such as Bode and root locus techniques, using 2-D graphics terminals, allow the engineer to assess very rapidly the behaviour of the system and picture, in a broad sense, the effect of compensation on it. Various powerful, new control design techniques are now available or are emerging. However they are characterised by a necessary mathematical abstraction which renders them difficult to understand for the majority of industrial engineers. Two-dimensional systems is one such area. The displays required to visualise these systems are essentially three-dimensional in nature. Modern graphical visualisation techniques used in the creation of virtual environments offer a new approach to computer aided control system design and appear to be ideal for the analysis of two-dimensional systems. Silicon Graphics hardware and software have been used to create initial virtual environments that aid the analysis and design of two-dimensional systems. These initial environments allow the user to interact with 3-D frequency response plots and 3-D output response plots. Current work also includes the generation of a graphical 2-D system compensation tool.