Software for Teaching and Learning

This demonstration package addresses fundamental concepts in control systems, including contruction of root locus, transfer functions, construction of a Bode plot and deeterminiation of gain and phase margin. Nyquist plots are also illustrated. The step response is shown in a traditional format (output versus time) and via an X-Y plotter. In the X-Y display two independent positioners are animated. The horizontal positioner has dynamics and gain set by the input file and sliders. The vertical positioner has the same poles and zeros but half the gain value.

The 's-plane' display permits open-loop poles and zeros to be selected (left click). The selected pole (zero) may then be moved via the sliders. The two gain sliders adjust the forward gain (K) of the system. Open loop poles and zeros are defined in .txt files for convenient editing.These are loaded via the 'user' menu.

Each of the tab windows support various options via a (left click) popup menu. Most include a 'toggle display' option. In the root locus window, for example, the visibility initially shows the salient features of the plot which students would ascertiain during construction of the plot (breakaway points, departure angles...). Toggling the display then reveals the root locus curves. This permits students to verify their work during the plot construction and then guess the curvature prior to seeing a final result. A similar incremental type of display is used for the Bode plots.

Note in the current version of this demo, H(s) = 1.

Download Control Systems Demonstration

Learning Objectives

The following learning objectives are associated with the above demonstration, with supporting lecture.