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Performance Evaluation and Requirements Assessment for Gravity Gradient Referenced Navigation.

Lee J, Kwon JH, Yu M - Sensors (Basel) (2015)

Bottom Line: It is found that DB and sensor errors and flight altitude have strong effects on the navigation performance.Considering that the accuracy of currently available gradiometers is about 3 E or 5 E, GGRN does not show much advantage over TRN at present.However, GGRN is expected to exhibit much better performance in the near future when accurate DBs and gravity gradiometer are available.

View Article: PubMed Central - PubMed

Affiliation: Department of Geoinformatics, University of Seoul, Seoul 130-743, Korea. leejs@uos.ac.kr.

ABSTRACT
In this study, simulation tests for gravity gradient referenced navigation (GGRN) are conducted to verify the effects of various factors such as database (DB) and sensor errors, flight altitude, DB resolution, initial errors, and measurement update rates on the navigation performance. Based on the simulation results, requirements for GGRN are established for position determination with certain target accuracies. It is found that DB and sensor errors and flight altitude have strong effects on the navigation performance. In particular, a DB and sensor with accuracies of 0.1 E and 0.01 E, respectively, are required to determine the position more accurately than or at a level similar to the navigation performance of terrain referenced navigation (TRN). In most cases, the horizontal position error of GGRN is less than 100 m. However, the navigation performance of GGRN is similar to or worse than that of a pure inertial navigation system when the DB and sensor errors are 3 E or 5 E each and the flight altitude is 3000 m. Considering that the accuracy of currently available gradiometers is about 3 E or 5 E, GGRN does not show much advantage over TRN at present. However, GGRN is expected to exhibit much better performance in the near future when accurate DBs and gravity gradiometer are available.

No MeSH data available.


Horizontal error of trajectory No. 12: (a) entire flight and (b) before 100 s.
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sensors-15-16833-f004: Horizontal error of trajectory No. 12: (a) entire flight and (b) before 100 s.

Mentions: As expected, better navigation results are obtained when initial errors are not imposed. However, the initial errors are compensated for rapidly in the case of DB and sensor errors of 0.1 E and 0.01 E, respectively. Figure 4 shows the horizontal error of trajectory No. 12 when four different initial position errors are imposed. It is found that the effect of the initial error appears mostly in the starting zone, and the performance improves once the filter converges; therefore, similar navigation results are obtained despite a large initial horizontal position error of 1800 m. When the worst possible accuracies are considered for the sensor and DB, the positions frequently diverge in the case of imposing initial errors. Therefore, it is crucial to develop and construct an accurate sensor and DB to correct the initial errors.


Performance Evaluation and Requirements Assessment for Gravity Gradient Referenced Navigation.

Lee J, Kwon JH, Yu M - Sensors (Basel) (2015)

Horizontal error of trajectory No. 12: (a) entire flight and (b) before 100 s.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4541910&req=5

sensors-15-16833-f004: Horizontal error of trajectory No. 12: (a) entire flight and (b) before 100 s.
Mentions: As expected, better navigation results are obtained when initial errors are not imposed. However, the initial errors are compensated for rapidly in the case of DB and sensor errors of 0.1 E and 0.01 E, respectively. Figure 4 shows the horizontal error of trajectory No. 12 when four different initial position errors are imposed. It is found that the effect of the initial error appears mostly in the starting zone, and the performance improves once the filter converges; therefore, similar navigation results are obtained despite a large initial horizontal position error of 1800 m. When the worst possible accuracies are considered for the sensor and DB, the positions frequently diverge in the case of imposing initial errors. Therefore, it is crucial to develop and construct an accurate sensor and DB to correct the initial errors.

Bottom Line: It is found that DB and sensor errors and flight altitude have strong effects on the navigation performance.Considering that the accuracy of currently available gradiometers is about 3 E or 5 E, GGRN does not show much advantage over TRN at present.However, GGRN is expected to exhibit much better performance in the near future when accurate DBs and gravity gradiometer are available.

View Article: PubMed Central - PubMed

Affiliation: Department of Geoinformatics, University of Seoul, Seoul 130-743, Korea. leejs@uos.ac.kr.

ABSTRACT
In this study, simulation tests for gravity gradient referenced navigation (GGRN) are conducted to verify the effects of various factors such as database (DB) and sensor errors, flight altitude, DB resolution, initial errors, and measurement update rates on the navigation performance. Based on the simulation results, requirements for GGRN are established for position determination with certain target accuracies. It is found that DB and sensor errors and flight altitude have strong effects on the navigation performance. In particular, a DB and sensor with accuracies of 0.1 E and 0.01 E, respectively, are required to determine the position more accurately than or at a level similar to the navigation performance of terrain referenced navigation (TRN). In most cases, the horizontal position error of GGRN is less than 100 m. However, the navigation performance of GGRN is similar to or worse than that of a pure inertial navigation system when the DB and sensor errors are 3 E or 5 E each and the flight altitude is 3000 m. Considering that the accuracy of currently available gradiometers is about 3 E or 5 E, GGRN does not show much advantage over TRN at present. However, GGRN is expected to exhibit much better performance in the near future when accurate DBs and gravity gradiometer are available.

No MeSH data available.