Choosing appropriate background field data is crucial for gravity field matching navigation.Current research mainly uses gravity anomaly data or gravity gradient data as background fields.However,using gravity gradien...Choosing appropriate background field data is crucial for gravity field matching navigation.Current research mainly uses gravity anomaly data or gravity gradient data as background fields.However,using gravity gradient invariants in existing research is seldom a concern.The gravity gradient tensor has three invariants,named as I_(1),I_(2)and I_(3).I_(1) is a Laplace operator outside the Earth and a Poison operator inside the Earth.The focus of this study is to discuss the performance of the other two invariants of gravity gradients in matching navigation based on the Iterative Closest Contour Point(ICCP)algorithm and compare the matching results with that of the gravity gradient Tzz.The results show that they have almost the same performance when there is no noise,and the background data noises have a large impact on the matching results.There are differences in the anti-interference ability of observation noises for the different components.Under the same random noises in the observations,I2performs a little better than the other two components in terms of position error standard deviation.According to the investigations,since attitude errors can not be avoided and influence the positioning based on Tzz,we recommend adopting invariants of gravity gradients,especially I2,for matching navigation in actual cases.展开更多
In order to achieve long-term covert precise navigation for an underwater vehicle,the shortcomings of various underwater navigation methods used are analyzed.Given the low navigation precision of underwater mapmatchin...In order to achieve long-term covert precise navigation for an underwater vehicle,the shortcomings of various underwater navigation methods used are analyzed.Given the low navigation precision of underwater mapmatching aided inertial navigation based on singlegeophysical information,a model of an underwater mapmatching aided inertial navigation system based on multigeophysical information(gravity,topography and geomagnetism)is put forward,and the key technologies of map-matching based on multi-geophysical information are analyzed.Iterative closest contour point(ICCP)mapmatching algorithm and data fusion based on Dempster-Shafer(D-S)evidence theory are applied to navigation simulation.Simulation results show that accumulation of errors with increasing of time and distance are restrained and fusion of multi-map-matching is superior to any single-map-matching,which can effectively determine the best match of underwater vehicle position and improve the accuracy of underwater vehicle navigation.展开更多
基金funded by the Key Laboratory of Smart Earth(No.KF2023YB01-12)the National Natural Science Foundation of China(No.42074017)+1 种基金the Key Laboratory Fund Project for Simulation of Complex Electronic Systems(614201004022210)the Chinese Academy of Sciences Youth Innovation Promotion Association(2022126)。
文摘Choosing appropriate background field data is crucial for gravity field matching navigation.Current research mainly uses gravity anomaly data or gravity gradient data as background fields.However,using gravity gradient invariants in existing research is seldom a concern.The gravity gradient tensor has three invariants,named as I_(1),I_(2)and I_(3).I_(1) is a Laplace operator outside the Earth and a Poison operator inside the Earth.The focus of this study is to discuss the performance of the other two invariants of gravity gradients in matching navigation based on the Iterative Closest Contour Point(ICCP)algorithm and compare the matching results with that of the gravity gradient Tzz.The results show that they have almost the same performance when there is no noise,and the background data noises have a large impact on the matching results.There are differences in the anti-interference ability of observation noises for the different components.Under the same random noises in the observations,I2performs a little better than the other two components in terms of position error standard deviation.According to the investigations,since attitude errors can not be avoided and influence the positioning based on Tzz,we recommend adopting invariants of gravity gradients,especially I2,for matching navigation in actual cases.
基金This work was supported by the National Defense Pre-Research Foundation of China.
文摘In order to achieve long-term covert precise navigation for an underwater vehicle,the shortcomings of various underwater navigation methods used are analyzed.Given the low navigation precision of underwater mapmatching aided inertial navigation based on singlegeophysical information,a model of an underwater mapmatching aided inertial navigation system based on multigeophysical information(gravity,topography and geomagnetism)is put forward,and the key technologies of map-matching based on multi-geophysical information are analyzed.Iterative closest contour point(ICCP)mapmatching algorithm and data fusion based on Dempster-Shafer(D-S)evidence theory are applied to navigation simulation.Simulation results show that accumulation of errors with increasing of time and distance are restrained and fusion of multi-map-matching is superior to any single-map-matching,which can effectively determine the best match of underwater vehicle position and improve the accuracy of underwater vehicle navigation.