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Study On Ins/gns/cns Integrated Navigation System Of Aerocraft

Posted on:2012-11-15Degree:DoctorType:Dissertation
Country:ChinaCandidate:R LiuFull Text:PDF
GTID:1112330362450140Subject:Control Science and Engineering
Abstract/Summary:PDF Full Text Request
Based on characteristics of multiple navigation modes, integrated navigation system can benefit from each of them, and can be more accurate and dependable. The integrated navigation system is the most important navigation mode at present. It is widely used in military and civilian area.Inertia, geomagnetism and celestial navigation systems are all analyzed respectively in this paper and this paper also analyze the theoretical and technical problem relate to realization of inertia/ geomagnetism/ celestial integrated navigation system. The research works focus on these points:1) Reference geomagnetic map is established based on high accuracy Kriging interpolation algorithm. Based on the analysis of the high mismatch rate and bad real-time when correlation algorithm is applied on gently area of geomagnetic field, a probability correlation algorithm rely on grey correlation is put forward, and the affect of positioning error comes from reference geomagnetic map and geomagnetic sensor noise is also analyzed. The algorithm has good performance even in anomaly magnetic field weak area, and the matching does not need the accumulation of time and path. The matching real-time is improved, and the algorithm is valuable in the application on engineering.2) Aim at the characteristic of geomagnetic navigation, an inertia/ geomagnetism integrated navigation algorithm based on EKF is studied. Analyze the causes that the filter is divergent when the interpolation algorithm is applied in the gently area of anomaly geomagnetic field. An adaptive fuzzy Kalman filter is put forward, it adjust the variance of measurement noise real-timely to keep the filter accurate and make the system stabile.3) Deal with the error accumulation of inertia navigation system, inertia/ celestial autonomous integrated navigation algorithm is put forward. This algorithm makes the celestial altitude and azimuth angle as the observed quantity, and the horizontal reference of which is provided by the inertia navigation equipment, so the algorithm is real-time and positioning accuracy of the navigation system is improved. Because the statistical characteristics of measurement noise may change when the algorithm is applied on engineering, a filter based on adaptive interacting multiple model is put forward. The application of this algorithm requires the model set should be pre-defined, and the actual modal should be covered by a model set as small as possible when the statistical characteristics of measurement noise changes, to ensure this algorithm is adaptive. It covers the change of actual modal well. Navigation parameter does not jump intensely when the observed quantities are abnormal, the filtering precision and stability are both high, and the whole navigation system is more accurate and dependable.4) Analyze the working process of full flight time inertia/ geomagnetism/ celestial integrated navigation algorithm, and test it by simulation. Based on the problem that the integrated navigation system is interrupt by error information when the inertia/ celestial or inertia/ geomagnetism subsystem is breakdown, a fault-tolerant filtering algorithm is put forward to improve the stability of the system. Deal with the breakdown of inertia navigation system, an autonomous navigation algorithm based on geomagnetism/ celestial information is put forward, this algorithm benefits form vectorialproperty of geomagnetism field, makes the angle between starlight and geomagnetism vector as its observed quantity, uses UKF to estimate the navigation parameter of the aircraft. Digital and the hardware-in-the-loop simulation both show that this algorithm is feasible. It can be used in either plain or ocean which has no obvious landmarks, and also can be the backup navigation system.
Keywords/Search Tags:Integrated Navigation System, Geomagnetic Matching, Grey Relational Probability Analysis, Astronomy Altitude Angle and Azimuth, Angle Between Starlight and Geomagnetic Vector
PDF Full Text Request
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