I found three definitions for the attitude angles of the ISS (yaw, pitch and roll), from three different source. They contradict each other. See the following pictures.

For my problem, I have to reconstruct ISS orientation in ECEF/ITRF coordinates, and I got values of yaw=-4.499, pitch=-0.7688 and roll=0.2870 (that are the values for the ISS on March 24th 2019 at 00:31:53:135 UTC). But I am not 100% sure which convention (from the three possibilities) should be used here. (For information, the corresponding ISS position is : altitude=409.6km, longitude=55.334deg and latitude=0.112deg)

Does anyone have any idea about which of the three definitions should these values correspond to ? And with a good justification of why, if possible. (I actually have an idea but I prefer to not give it so I get independent opinions)

Thanks in advance

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There is no 'contradiction', all are valid attitudes.1

The one you choose depends on what you want to use it for.

The most commonly used of these frames in Mission Operations (for robotics, EVA, etc.) during the shuttle era was ISSACS (the second one pictured in the question).

LVLH is used for matters involving the Earth (observations, etc).

1 the first LVLH one appears to have an error in the drawing; the right hand rule may be violated in the pitch axis - pitch up should be positive. Otherwise the first and third are identical.


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