Control Systems: HP prime app, now with frequency, time domain and root locus plots

[hata]

This new Control Systems App for the HP Prime is used to study the frequency and time domain responses of control systems consisting of a process and a controller, as well as stability - the app produces Root Locus Plots.
• In the frequency domain, open loop response with and without controller and resulting closed loop response (unity feedback loop) can be determined / compared.
• In the time domain, the app calculates the open loop and unity feedback loop response to reference changes as well as to disturbances (appearing between controller and process). It also calculates and visualizes the controller output. Input types: Dirac pulse, unit step and ramp.

Although the app type is ‘Parametric’, the app does not rely on the built in HP Prime parametric plot mechanism but on custom plotting routines, including custom mouse movement handling, key press detection and custom soft key menus to accomplish functionality that would not be possible otherwise. The app is entirely menu based (no need to type in commands).

The app takes as input the transfer function of a process as well as the settings of a (PID) controller.
Plot types: Nyquist, Nichols, Bode, Time domain response, root locus.
Bode plot will show magnitude and phase angle charts on one screen, or you can choose to plot magnitude or phase angle only (enlarged). Bode plots real log scales for frequency and magnitude. Magnitude can be displayed in dB as well.
Time domain plot will also show controller output or error signal.
Root locus plot will highlight all roots for a given gain and indicate whether the system is stable.

An extensive user quide is included in the zipped folder attached.
Have a look at the screen captures attached to this thread.

Note: a previous version of this app (only capable of plotting frequency response, and still relying on standard HP Prime plotting) was posted in a different thread ("Control Systems app for HP Prime").

Please let me know your comments and feedback.

Update May 2021: new Control Systems App version v3.01 available (attached), fixing a few issues (see this thread) and tested with new HP Prime version 2.1.14588 (2021 05 05). Updated manual included as well