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Now we will learn about TF2.

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TF2 is a very important tool in Ros two and it keeps a track of different frames.

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And it can also provide you the transformation from one frame to another frame.

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It will like ease your work.

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You will not need to calculate the transformation matrix from one frame to another, and it will be

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a big trouble if you do that.

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You can just use the library and feel at ease.

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So here is the command to install different tools that are related to the TF.

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Open the terminal and paste it.

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Now we will try to run a demo using the same copy this.

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And now this will launch our turtle.

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One turtle is following the other.

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If we move one turtle, the other one will be following the first one.

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So how does it do that?

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It is just using the library in order to find out the relative pose.

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And it is trying to go there and trying to reach there.

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Here we have one that will tell us transformation from one frame to another for us to run and TF2,

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Ros, TF2, ICO and the run frame and will speak to another frame.

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Copy it here, paste it.

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So it is giving us the information about the transformation.

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And if I try to move, you will see the change in the transformation.

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These values are in the quaternion.

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These are not the values.

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As the Turtle two approaches turtle one the distance value will be minimized.

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We can also visualize this thing on the iris.

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So the iris is a tool that will enable you to visualize the data on different topics.

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We will run this command in order to see the relation between these two frames.

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It has opened the race to here we are seeing two frames.

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So here we are seeing just one frame because two turtles are aligned with each other.

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And if I try to move one there, you will be seeing the distance between them.

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Okay.

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Let me explain you what this command does.

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It just runs our issue.

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And then it loaded our configuration file that will be representing if we want to avoid this, we do

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not have any information about the configuration file.

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How can we visualize this?

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We can just run our face to hit enter.

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All right.

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We are not loading any configuration file.

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There you see different frames that are available to you.

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I will select a fixed frame, which is default frame, and now I will add TF2.

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There are tons of different things that you can add, but.

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But currently we are just utilizing one thing that is tf and we will visualize it and.

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Click here.

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There we have three frames, and if we see the three, there is per frame.

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And then there are two child frames.

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There are Turtle one and turtle two.

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So the first frame is the parent frame.

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Now we can form it in.

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Now, if I try to move one turtle and you will be seeing the moving frame.

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The word frame is this one and it is fixed.

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And one that moves first is a turtle one and then one that follows a sea turtle.

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Two.

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We can also utilize the names.

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There we go.

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The word frame and turtle one and turtle two are, like, mixed with each other.

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And Turtle one goes forward and turtle two goes behind it.