This check processes the Attitude History File in order to determine the
stability of the attitude reconstruction. odfcheck
estimates the
stability of the attitude reconstruction by calculating the r.m.s.
of the parameters DIFFVRA and DIFFVDEC in the AHF, during the
stable pointing period (after the completion of the closed loop slew
where VALTIME
PTTIME).
If either of the parameters exceeds a user supplied threshold, a warning is issued.