Help for RLTOOL.


1. Starting RLTOOL:
load the rltool library as per instructions in the README file. If the library loads properly the following message is displayed on Scilab prompt:
                                                                                                              mode(-1);

rltool is loaded;
enter "rlt()" to start

Type rlt() to start this programme.

2. Using RLTOOL:
It is intended to make RLTOOL very user friendly and as such most features should be obvious. However, these are given below for the sake of completness.

On execution, the user is prompted to enter the transfer function as numerator / denominator in the variable 's'. The default value is set to '1/s'. Edit these values and enter polynomials in s. Press OK when you have entered the transfer function. A Rootlocus plot of the transfer function is displayed. Open loop poles are shown by crosses and zeros by circles. Click on any point of the rootlocus plot to know the gain and closed loop poles corresponding to that point. At any time you can choose the frequency design mode by clicking on  "Design->Frequency". This displays the magnitude plot of the open loop transfer function. Click on any point of the magnitude plot to know the magnitude in dB and frequency in Hz. You can revert back to root locus mode by clicking on "Design->Root Locus". A choice of various plots is available as below

3. Editing of plants:
  1.  Undo: You can undo one change of transfer function. Click on "Edit-> Undo" to cancel your last change. You will have to select a working directory where you have write permission to use this feature. The working directory can be set in "Settings->PWD".
  2.  Add pole: Available in Rootlocus mode. Click on "Edit->Add Pole". Click on any point in the complex plane. If you clicked at a real valued point it is selected. If you clicked at a complex valued point then both the point and its complex conjugate are selected.
  3.  Add zero: Available in Rootlocus mode. Click on "Edit->Add Zero". Click on any point in the complex plane. If you clicked at a real valued point it is selected. If you clicked at a complex valued point then both the point and its complex conjugate are selected.
  4.  Remove pole: Available in Rootlocus mode. Click on "Edit->Remove Pole". Click on any point in the complex plane. If you clicked at a real valued point it is selected. If you clicked at a complex valued point then both the point and its complex conjugate are selected.
  5.  Remove zero: Available in Rootlocus mode. Click on "Edit->Remove Zero". Click on any point in the complex plane. If you clicked at a real valued point it is selected. If you clicked at a complex valued point then both the point and its complex conjugate are selected.
  6.  Add Cascade stage: Available in all modes. Click on "Edit->Add Cascade". You will be prompted to enter a transfer function. This gets multiplied with your current open loop transfer function.
  7. Remove Cascade stage: Available in all modes. Click on "Edit->Remove Cascade". You will be prompted to enter a transfer function. This divides your current open loop transfer function.
  8.  Edit Plant: Available in all modes. Click on "Edit->Edit Plant" to directly edit your current plant.


4. Saving and loading plants: -
 

  1. Saving: To save your current plant, click on "Save->Save". You will be prompted to enter filename.
  2.  Loading: To load existing plant from a file, click on "Save->Load". You will be prompted to enter the filename.
5. Settings:

RLTOOL allows users to set parameters for plots and simulations. Click on "Settings" to edit these settings. Press OK to load these new settigs. Press CANCEL to return. This loads the Default settings. You have the following settings


6. Help:

Short online help is provided on many topics.

7. Quit:

Click on "Quit" to quit rltool programme. If you don't see this button on your graphics panel, pull down your graphics window a bit. You can do this by dragging down a small black square on the top right corner of the graphics window. Alternately, close RLTOOL by clicking the "X" mark on your window.



end of help for RLTOOL
author: Ishan Pendharkar, ishan@ee.iitb.ac.in