‫Now, you might think that this is all.
‫However, it's not what we have discussed so far is rotation about an axis using fixed angles.
‫We call them fixed angles because we have been rotating our body frame about the fixed inertial frame
‫axis.
‫However, you can also rotate your body frame about, for example, first Z axis by 90 degrees, then
‫you will end up in this configuration.
‫But now, instead of rotating about the inertia frame y axis, you can rotate about the body frame y
‫axis and then you will end up in this configuration if you rotate by 90 degrees.
‫When you do that, then we say that you're using oilor angles, not fixed angles.
‫In other words, you're rotating about the moving frame, not about the fixed frame, about the moving
‫frame.
‫So you also have to specify that when describing an attitude of an object in space and you also have
‫12 conventions there.
‫We will discuss it more in the next video.
‫Thank you very much.