I2B:

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   Transforms the sun vector defined in the ECI xz-plane into
   the spacecraft whose nominal frame is with the +z axis pointing
   at the earth, +y along orbit anti-normal and +x completing the right-hand
   set. The spacecraft rotates about the +z axis with alpha.

   Since version 1.
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   Form:
   uB = I2B( q, uI )
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   ------
   Inputs
   ------
   q           (4,1)   Quaternion from the inertial to the body frame
   uI          (3,1)   Sun vector in the I frame

   -------
   Outputs
   -------
   uB          (3,1)   Sun vector in the B frame

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Children:

Common: Quaternion/QForm