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‫Welcome back.

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‫So I want to talk a little bit more about those conventions, what I want you to understand is that

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‫the drones attitude is not different, depending on which convention you choose.

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‫The drones attitude is what it is.

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‫And now you simply have to describe the altitude of the drone.

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‫And for that, you have different ways to do it.

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‫You have 24 different ways to describe the drones attitude if you use rotation matrices to describe

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‫it.

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‫You have 12 ways if you rotate about the fixed inertial frame axis and then you have 12 ways when you

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‫rotate about the moving body frame axis, but the drones altitude itself stays the same is just you

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‫have different conventions to describe the same thing.

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‫It's like describing some kind of distance either in meters or in feet.

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‫It's like either you use Cartesian coordinates to describe some kind of position or polar coordinates.

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‫So, for instance, if you choose to describe a drone's attitude with an inertial X, Y, Z convention

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‫where you first rotate about the inertial X axis, then about the inertial Y axis and then about the

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‫initial Z axis, then your Fifita and BPCI Angles will have some kind of values.

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‫But if you choose to describe the same thing with an inertial Z, Y, X convention where you first rotate

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‫about the inertial axis, then about the initial Y axis and then about the inertial x axis, then those

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‫angles will have different values.

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‫But again, the drones attitude is still the same is just you are describing this additive in a different

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‫way.

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‫And that's what conventions are all about.

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‫It's about having different ways to represent the same thing.

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‫Either you represent the attitude of the drone by rotating about the inertial X, Y, Z axis, where

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‫you have 12 different ways to do it, or you represent the same attitude.

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‫But by rotating about the moving body frame axis for which you also have 12 different ways to do it.

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‫So that's that.