When simulating the motion of a spinning projectile, it turns out to be computationally advantageous to select non-rolling frame measure numbers of the projectile mass center velocity and angular velocity for use in the equations of motion. Assume standard Euler angles using the aerospace rotation sequence (3-2-1) are used to define orientation. Reference frame N is the frame just before roll rotation (final rotation by roll angle 6). Let angular velocity be given by @/1 = pn + n + n. Solve for the rotational kinematic differential equations relating angular velocity measure numbers p, q, and the derivatives of Euler angles, y. Make sure to isolate the Euler angle derivatives on the left-hand-side of the equation. 9