A Novel Method for Target Navigation and Mapping Based on Laser Ranging and MEMS/GPS Navigation

Abstract

Making the sensor rigidly mounted in the target is the common characteristic of conventional navigation system. However, it is difficult or impossible to realize that for special applications such as the positioning of hostile aircraft. A novel new algorithm for target navigation and mapping is designed based on the position, attitude, and ranging information provided by laser distance detector (electronic distance measuring, LDS) and MEMS/GPS navigation, which can solve problem of the target navigation and mapping without any sensor in the target. The detailed error analysis shows that attitude error of MEMS/GPS is the main error source which dominated the accuracy of the algorithm. Based on the error analysis, a calibration algorithm is designed so as to improve the accuracy to a large extent. The result shows that, by using this new algorithm, the performance of target positioning can be efficiently improved, and the positioning error is less than 2 meters for the target within 1 kilometer range.

A Simultaneously Calibration Approach for Installation and Attitude Errors of an INS/GPS/LDS Target Tracker

“…According to the previous analysis in [ 35 ], each part of INS/GPS/LDS integrated system would inevitably have measurement error. Therefore, the actual coordinate should be expressed as: where, the variables with the superscript “∼” denote that their values contain errors.…”

“…Therefore, the actual coordinate should be expressed as: where, the variables with the superscript “∼” denote that their values contain errors. In [ 35 ], among the error sources, the attitude error of INS/GPS dominates the calculation accuracy. By introducing an outer reference point, the yaw error and pitch error of INS/GPS can be precisely estimated and compensated.…”

“…However, such kinds of solutions usually demand high-accuracy instruments, which could provide precise reference for installation, leading to over high requirement for machining as well as the cost. Based on the experience of calibration for the attitude error of INS/GPS in [ 35 ], soft calibration schemes appear to be more reasonable. It seems also available to estimate both the installation and attitude error by using the information of other reference points, which have been already precisely measured.…”

“…However, this method has a disadvantage that the obtained coordinates of the points are related to the measurement coordinate system [ 34 ]. In [ 35 ], a method is designed for target navigation and mapping based on the INS/GPS/LDS integrated system, in which inertial sensors are utilized to provide the rotation measurements to map the range information in the measurement coordinate system into that in the geographic coordinate. The impact of the attitude errors of inertial sensors on the mapping performance are consequently investigated and calibrated.…”

“…With a high-frequency update, this method could be used for target tracking. However, the work of [ 35 ] is based on an assumption that all the three subsystems are precisely installed. Before the real application, the misalignment error between the sensitive axes of INS/GPS system and LDS should be compensated to be minimum, to avoid an over large positioning error.…”