Graphical Simulation of an Analog Computer Using Spreadsheets

This paper presents a spreadsheet method for the graphical simulation of analog computers (AC) used in control systems. It is based on simulating basic AC blocks like adders, integrators, potentiometers, inverters, and nonlinear devices. To make the simulation simple and user friendly, the construction of an AC system is done graphically, whereby blocks are drawn at the simple clicks of buttons. Blocks can then be easily connected using a built-in graphical interface. The initialization and running of a given system is fully menu-driven and done using toolbars and buttons. The simulation of a system allows the calculation and plotting of its time response for any input signal. This toolbar-customized simulation is characterized by its low cost, flexibility, and simplicity. The procedure for building the graphical symbols and toolbars is briefly described, and illustrative examples are presented to show the capabilities of the developed simulation system.