View source for Scilab/C4/Simulating-a-PID-controller-using-XCOS/English-timed

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| Time
|  '''Narration'''

|-
| 00:01
| Welcome to the spoken tutorial on '''Simulating a PID controller using Xcos.'''

|-
| 00:07
| In this tutorial we will learn how to implement a '''PID controller '''in '''Xcos'''.

|-
|  00:13
|  Ensure that '''Scilab''' is installed on your computer.

|-
|  00:17
| I am recording this tutorial on '''Ubuntu 16.04 64-bit Operating System '''and using '''Scilab 6.0.0'''

|-
|  00:27
|  As a pre-requisite, watch the tutorial '''Xcos Introduction.'''

|-
|  00:32
| This tutorial will make you comfortable with the '''Xcos''' environment.

|-
|  00:37
| Also, we will use the '''firstorder.xcos''' file created in that tutorial. 

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|  00:43
| Hence, it is important that you practice the tutorial before continuing so that you have the file with you.

|-
|  00:50
| Some basic knowledge of '''PID controller''' is necessary.

|-
|  00:54
| Assuming that you have satisfied the pre-requisites, let us begin with the tutorial.

|-
| 00:59
|  First of all, we will launch '''Scilab.'''

|-
| 01:03
|  Then go to '''Applications '''and select '''Xcos'''.

|-
| 01:08
|  Or in your '''Scilab console''' window, type '''Xcos '''and press '''Enter'''.

|-
| 01:15
|  By doing this, two windows will open.

# '''Palette Browser''' and # '''An Untitled-Xcos''' window 

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| 01:23
| On the '''Untitled-Xcos''' window, click on '''File''' and then click on '''Open.'''

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| 01:30
| Browse to the directory where the file '''firstorder.xcos''' is saved. 

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|  01:36
| Choose that file and click on '''Ok'''.

|-
| 01:40
| Now, Double-click on the '''transfer function block'''. 

|-
| 01:44
|  Check that you are using the same '''transfer function''' as I am using.

|-
| 01:49
|  For me, the numerator is 1 and denominator is '''2 asteric s plus 1'''

Which is 2 multiplied by s plus one.

|-
|  02:01
| Click on '''Ok'''.

|-
| 02:03
|  Double-click on the '''Step block'''. 

|-
|  02:06
| Check that you are using the same '''step input''' parameters as I am using.

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|  02:11
|  For me the '''Step time''' is 1, the '''Initial value''' is 0 and the '''Final value''' is 2.

Click on '''OK'''
|-
| 02:20
| Click on '''Simulation''' on the menu bar and choose '''Start''' to simulate the file. 

|-
|  02:27
|  Expect a similar plot which ensures that the file has no mistakes.

|-
| 02:32
|  Switch to the '''Palette Browser.'''

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| 02:35
| Click on '''Continuous time systems''' category. 

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|  02:39
| Drag and drop the '''PID''' block, which is here, inside the '''Xcos''' window

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| 02:46
|  Click on the '''Signal Routing''' category. 

|-
|  02:49
| Drag and drop the '''Mux''' block, which is here, inside the '''Xcos''' window.

|-
| 02:55
| Click on '''Mathematical Operations''' category. 

|-
|  03:00
| Drag and drop the '''Summation''' block, which is here, inside the '''Xcos''' window.

|-
|  03:07
| Note that this block, by default, subtracts the second input from the first input.

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|  03:14
| We will use this default configuration of the '''summation''' block.

|-
| 03:18
| Click on the line joining the '''step input''' block and '''transfer function''' block.

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|  03:24
| Then press the '''Delete''' button to delete it.

|-
| 03:27
|  Drag the '''step input''' block away from the '''transfer function''' block.

|-
| 03:31
|  Click on the line joining the '''transfer function''' block and the '''cscope''' block.

|-
|  03:36
| Then press the '''Delete '''button to delete it.

|-
| 03:40
| Drag the '''cscope''' and '''clock input''' block away from the '''transfer function''' block

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| 03:46
|  Place the '''PID''' block before the '''transfer function''' block.

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| 03:50
| Place the '''summation''' block before the '''PID''' block.

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| 03:54
|  Place the '''Mux''' block between the '''transfer function''' block and '''cscope''' block.

|-
| 03:59
| Adjust the blocks, if required, so that they all come in a line.

|-
| 04:04
| Connect the '''step input''' block to the first '''input port''' of the '''summation''' block.

|-
|  04:10
| Note that this is the positive '''input port''' of the '''summation''' block.

|-
| 04:15
| Connect the '''output port''' of '''summation''' block to the '''input port''' of '''PID''' block.

|-
| 04:21
| Connect the '''output port''' of '''PID''' block to the '''input port''' of '''transfer function''' block.

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| 04:27
| Connect the '''output port''' of '''transfer function''' block to the lower '''input port''' of '''Mux''' block.

|-
| 04:33
|  Connect the '''output port''' of '''Mux''' block to the''' input port''' of the '''cscope''' block.

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| 04:39
| Locate the line connecting the '''step input''' block and the '''summation''' block.

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|  04:44
| Connect the '''input''' port of '''Mux''' to that line.

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| 04:48
| Use the left mouse click to create line bends while making the connection.

|-
| 04:54
| Locate the line joining the '''transfer function''' block and the '''Mux''' block.

|-
|  04:59
| Connect the second '''input port''' of the '''summation''' block to that line. Use line bends wherever necessary.

|-
| 05:08
| Double-click on the '''PID''' block to open its parameter setting dialog box.

|-
| 05:14
| Here you can set the '''Proportional, Integral '''and''' Derivative''' gains.

|-
|  05:18
| Please note that the '''Integral gain''' should be considered as 1 by '''tau I''', where '''tau I''' is the '''integral time'''.

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| 05:28
|  We will use the default settings. Click on '''Cancel''' to use the default settings.

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|  05:34
|  We are now ready to run the simulation.

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| 05:37
|  Notice that we are using the '''step input''' block as a '''setpoint''' variable.

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| 05:42
|  The '''PID controller '''will generate an input to the '''Transfer Function''' block.

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|  05:47
| It will be such that the output of the '''transfer function''' block matches the '''setpoint.'''

|-
| 05:53
| Click on  '''Start simulation''' button available on the menu bar.

|-
| 05:58
| Expect a graphic window to open. It will have two variables plotted in a single plot.

|-
|  06:07
| The step plot is the '''setpoint''' which has a final value of 2.

|-
|  06:12
| The curved plot which is green in color, is the output of the '''transfer function''' which tries to meet the '''setpoint''' value of 2.

|-
| 06:22
| You can now change the '''PID''' settings and learn how they affect the output.

|-
|  06:28
| Pause the video here and solve the given exercises.

|-
| 06:33
| Implement a '''Proportional Controller''' only. That is, only '''P''' and not '''PID'''

|-
|  06:40
| Change the proportional gain such that the setpoint matches the output but without overshoots.

|-
| 06:47
| Include the output of the '''summation''' block in the plot.

|-
|  06:51
| You may use '''CMSCOPE''' to keep it separate. 

|-
|  06:55
| Compare it visually with the output of the '''PID''' block

|-
| 06:59
| This brings us to the end of this tutorial. Let us summarize.

|-
| 07:04
| In this tutorial we learnt : To modify the '''firstorder.xcos''' file to implement a '''PID''' controller

|-
|  07:12
|  Configure each block as per the simulation requirements

|-
|  07:16
|  Setup the simulation parameters

|-
| 07:19
| The video at the following link, summarizes the Spoken Tutorial project.

Please download and watch it.

|-
| 07:26
| The Spoken Tutorial Project Team conducts workshops and gives certificates.

For more details, please write to us.

|-
|  07:34
|  Do you have questions in THIS Spoken Tutorial?

|-
|  07:37
|  Please visit http://forums.spoken-tutorial.org

|-
|  07:43
|  Choose the minute and second where you have the question

|-
|  07:47
|  Explain your question briefly

|-
|  07:50
| Someone from our team will answer them

|-
| 07:53
|  The Spoken Tutorial forum is for specific questions on this tutorial

|-
|  07:58
|  Please do not post unrelated and general questions on them

|-
|  08:03
|  This will help reduce the clutter

|-
|  08:05
|  With less clutter, we can use these discussions as instructional material

|-
| 08:11
| Spoken Tutorial Project is funded by NMEICT, MHRD, Government of India.. More information on this mission is available at the link shown.

|-
| 08:23
| This is Rupak Rokade signing off. Thanks for joining.
|-
|}