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‫Welcome back.

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‫So let's rotate the body frame with respect to the inertial frame by rotating about the fixed axis.

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‫So first we rotate about the fixed x axis, like this positive rotation according to the right hand

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‫rule.

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‫And if you rotated by 90 degrees, then you will get this result.

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‫Then you rotate about the inertial y axis and you have this and then about the Z axis and you are here.

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‫And now let's do the same thing.

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‫But now we rotate about the moving frame.

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‫So first we rotate about the body frame x axis by 90 degrees.

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‫You get this one, which is the same like this one here, which makes sense because when you rotated

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‫about the body frame x axis, then at the beginning your body frame x axis overlapped with the inertial

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‫frame x axis.

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‫So it's logical that here the result is the same like here.

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‫However, now instead of rotating about the inertia frame y axis, you rotate about the body frame y

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‫axis.

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‫And if you do that, then you will get this result.

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‫And finally, you rotate about the body frame Z axis, not the inertia frames the axis, but body frame,

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‫Z axis.

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‫And you end up having this configuration.

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‫There you go.

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‫As you can see, it also matters if you rotate about the fixed X, Y, Z axis, which is called a fixed

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‫angle approach, or you rotate about the moving X, Y, Z axis, which is called an oiler angle approach.

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‫So now you know how to completely determine the position and the orientation of your drone.

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‫You have to specify the position of the drone, the orientation angles, whether you use the right hand

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‫rule or not, and probably you do because everybody does it.

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‫Then you also have to specify the rotation order convention and whether you use a fixed angle approach

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‫or an oilor angle approach.

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‫But now a question to you.

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‫How would you rate the oil or angles in the vector matrix form?

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‫And for that, I'm going to give you another exercise again.

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‫At the beginning, your body and inertial frames overlap, then make three consecutive rotations each

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‫power to radians, first using the R sub X, Y, Z convention using the fixed angle approach and then

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‫R sub z, y, x convention using the oilor angle approach.

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‫Try to do this exercise by yourself first and see what you will get.

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‫See how in both cases the body frames end up in which configuration.

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‫See you in the next video.