LaTeX/C3/Feedback-control-diagram/English-timed

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Time Narration
0:00 Welcome to the spoken tutorial on feedback diagram creation using Xfig
0:07 In the spoken tutorial on block diagram creation, We created the diagram shown here
0:14 We will refer to it as the blocks tutorial
0:18 Please master the blocks tutorial before starting the current one
0:22 In this tutorial, we will explain how to create block diagrams of the type shown on this page
0:31 I shall use Xfig, version 3.2, patch level 5
0:37 We will begin with block.fig created in the blocks tutorial
0:43 Let us go to Xfig
0:47 Let us choose the file, then open.
0:52 In the entry box, we can enter “block” and press open.Or double click on “block.fig”.
1:04 Using the “save as” option on “file”, we will save this figure as feedback.
1:24 We now have the file feedback.fig
1:28 Let us put the grids on by clicking on the “grids”
1:34 The scroll bar on the right can be used to move the canvas up or down.
1:41 The role of each mouse button is shown on the top right hand side.
1:46 This role depends on the activity.
1:49 To illustrate this, let me take the mouse to the vertical “scroll bar”.
1:55 Observe the comment next to the left button.
1:59 I cannot move the mouse to show this. It is because, the role of the buttons will change if I move the cursor away from the scroll bar.
2:08 The “left button” moves the canvas up and the “right button” moves it down.
2:17 Instead of clicking the left or right button, we can also click the “centre button”, hold and drag the canvas up or down
2:31 In a similar way, you can move the canvas to the right or left, using the “scroll bar” on the top. Left, right
2:44 I will now move the box to the centre by clicking the “middle button”, holding and dragging the canvas to the centre.
2:57 As I release the mouse, the box gets moved to the centre.
3:03 Let us now create the feedback diagram starting from this block.
3:08 Let us copy this box.
3:13 Click on the box and select it.
3:16 Move the mouse to the new location and click.
3:27 Let us now put some text.
3:29 Let us click the “Text box”, indicated by T, from the left hand side panel.
3:37 Let us choose the size of the text.
3:43 Move the mouse to the value box and enter 16.
3:51 Click “Set”.
3:53 Let us click the “Text Just” button in the attributes panel.
4:02 Let us choose centre alignment.
4:05 Let us click at the centre of the first box.
4:11 Sorry, I did not choose the correct position.
4:15 I will click at a different location to move the cursor away.
4:19 I will then click at the correct position.
4:27 Let us now type the text “Control” and click the mouse.
4:35 We would now want to enter some more lines with arrows.
4:40 Let us choose the “polyline button”
4:43 Let us select the “Arrow Mode” button from the attributes panel and select the second option.
4:53 Let us click the “Arrow Type” button and an arrow head.
5:00 Let us click at the point where we want the line to start.
5:08 Let us move the mouse to the end point of the desired line.
5:14 Let us now click there with “middle mouse button”.
5:20 The line is created with an arrow.
5:25 I want to place a circle.
5:27 Let us choose the “circle on the left” from the “left hand side panel”.
5:33 We will place it to the left of the first box.
5:37 Click the mouse. As I move the mouse, the circle becomes bigger.
5:47 When we get the right size, let us release the mouse button.
5:54 Oops, the circle is larger than what I wanted.
5:57 I can undo this operation, using the edit button at the top.
6:02 We can also delete this object, using the Delete button on the left hand panel.
6:10 Let us do that now.
6:14 A skeleton with cross hairs appears.
6:18 All key points of all objects also appear.
6:22 Move the cross hairs to a key point that indicates the circle and click.
6:32 In case a wrong object is deleted, no need to panic.
6:35 You can undo it: Click the “edit” button, hold, go to “Undo” and release the mouse.
6:44 If some objects are closely placed, you may have difficulty in choosing them.
6:49 You can solve this through the “zoom” feature.
6:55 Click the “View” button on the top left hand side, hold and choose one of the zoom options.
7:00 Let me release the mouse at “Zoom to fit the canvas”.
7:04 Now it is easy to discriminate between the objects.
7:08 Let me delete the circle now.
7:12 Let me unzoom.
7:20 I will move the diagram to the centre with the use of scroll buttons.
7:35 I do not like to leave “delete” symbol on, because I can accidentally delete something else.
7:41 I can change this by choosing any other button.
7:44 Let me choose the left circle.
7:47 Let me redraw the circle
8:00 I want to put another line from this line.
8:04 For this, we will first put a “dot” on the line.
8:07 Let us click the “library” on the left hand side panel.
8:11 The library is indicated by a stack of books.
8:15 A “dialog window” opens.
8:17 Next to the library, it says “None Loaded”.
8:20 Let us click and hold.
8:22 A list of available libraries appears.
8:25 Move the mouse to the “Logic library” and release the mouse .
8:31 Let us choose the “small dot” by double clicking on it.
8:36 The “dialog window” gets closed.
8:38 We see a cross hair, along with the chosen small dot.
8:42 Let us place the dot on the line by clicking.
8:51 The cursor and the small dot show up once again, suggesting that we can place it at some other location also.
8:57 We do not want to place the dot at any other place.
9:00 Let us close it by clicking the right button of the mouse.
9:05 The right button does an “undo” operation.
9:08 In this case, dot selection has been removed.
9:10 Let us draw a line from this dot to the circle.
9:15 Let us select the polyline.
9:18 Notice that the previous selections of “arrow mode” and “arrow type” have been remembered.
9:24 Within a session, Xfig remembers the parameter values.
9:28 Click at the dot.
9:34 Move the mouse to the bottom and click.
9:41 Now turn the mouse to the left, until at the bottom of the circle. Click.
9:47 Move the mouse to the circle and now click the “middle mouse button”.
9:54 Let us draw another line, to the left of the circle by copying.
10:08 Let us now save this figure using the “file button” at the top left hand corner of Xfig and choosing “save”.
10:19 Let us now export the file.
10:22 Let us click the “file” button once again and choose “export”.
10:30 Let us choose “language” and then “PDF”.
10:36 We get the file “feedback.pdf”.
10:43 Let us open this file through the command “open feedback.pdf”.
10:56 We now have the block diagram that we wanted.
11:00 We have completed our objective.
11:04 We have an assignment for you
11:08 Substitute the blocks with different objects.
11:13 Try out operations, such as, rotate and flip.
11:19 View the file feedback.fig in an editor, and identify different components.
11:25 Using the library, create entirely different block diagrams.
11:32 Spoken Tutorial is a part of the Talk to a Teacher project Supported by the National Mission on Education through ICT (NMEICT), MHRD, Government of India.
11:44 More information on this mission is available at

http://spoken-tutorial.org/NMEICT-Intro

11:53 We welcome your participation and also your feedback.
11:57 This is Kannan Moudgalya signing off. Thanks for joining. Goodbye.

Contributors and Content Editors

Minal, Nancyvarkey, Pratik kamble, Sandhya.np14