The antenna A in Figure below is oriented with the following three rotations: 1. Azimuth, about...

 

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The antenna A in Figure below is oriented with the following three rotations: 1. Azimuth, about y fixed in G, at the rate wJ/G = 5t rad/sec 2. Elevation, about 2 fixed in a first intermediate frame J, at the constant rate wJ/J = 1 rad/sec. 3. A polarization rotation about the antenna axis 2 (fixed in both the second intermediate frame J and in A) at wA/J =5t rad/sec. If the structure is in the = 0 position at t = 0, find the magnitude of wA/G at the time t = /2 sec. The easiest way to represent the angular velocity vector in a single reference frame is to use the unit vectors fixed in direction in J: parallel to y, parallel to z, and 2 = 3 x k to do your calculations. Two of the three simple angular velocities are directly represented in this reference frame. The third angular velocity is known about 2 and can be written in terms of (1, 3, k) unit vectors - this transformation is dependent only on (t). o(t) can be written in terms of wJ/J A J Azimuth bearing Figure is from "Engineering Mechanic An Introduction to Dynamics" McGill and King The antenna A in Figure below is oriented with the following three rotations: 1. Azimuth, about y fixed in G, at the rate wJ/G = 5t rad/sec 2. Elevation, about 2 fixed in a first intermediate frame J, at the constant rate wJ/J = 1 rad/sec. 3. A polarization rotation about the antenna axis 2 (fixed in both the second intermediate frame J and in A) at wA/J =5t rad/sec. If the structure is in the = 0 position at t = 0, find the magnitude of wA/G at the time t = /2 sec. The easiest way to represent the angular velocity vector in a single reference frame is to use the unit vectors fixed in direction in J: parallel to y, parallel to z, and 2 = 3 x k to do your calculations. Two of the three simple angular velocities are directly represented in this reference frame. The third angular velocity is known about 2 and can be written in terms of (1, 3, k) unit vectors - this transformation is dependent only on (t). o(t) can be written in terms of wJ/J A J Azimuth bearing Figure is from "Engineering Mechanic An Introduction to Dynamics" McGill and King