As an extension of the idea of the micro delta-position aiding, we can consider sensor measurements where the same patch of the seafloor is seen with an arbitrarily large time interval between the measurements. As an example, consider the detection of mine-like objects from sidescan images. If the AUV passes the same object multiple times, and the localisation accuracy of the object is mainly contributed to the AUVs navigation accuracy, then the difference between the object's estimated position from the two observation times gives a valuable measurement of relative position error of the AUV. This type of measurement can be integrated with an INS, and the technique is herein called macro deltaposition aiding. Another example, closely related to CMN, is to use sparse bathymetric information from an interferometric sonar covering overlapping regions during the mission. After running one of the terrain navigation algorithms, we will be able to make a macro delta-position measurement for the INS.
This technique is fully autonomous, but requires an imaging or bathymetric sensor. It is also only possible to bind the position error drift with this technique. The initial global error of the AUV is not observed, as can be done with regular terrain navigation
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