Summary: | 碩士 === 中華大學 === 機械與航太工程研究所 === 87 === Abstract
The research is for the software design of a three dimensional navigation system by integrating GPS with INS. We use the GPS receiver to receive the raw data of satellite broadcast ephemeris, and to obtain the position of the satellite in WGS-84 coordinate frame. Then, using the least squared-error method to solve the navigation equations for positioning. INS is one kind of a self-contained system, it doesn''t need any other outside information. It depends on the inertial-components, for example: accelerometers and gyroscopes to measure the angular velocity and acceleration of vehicle motion, Along with the initial data, we can get the position, velocity, and attitude of the vehicle. This research is to study the loosely-coupled closed-loop structure of INS with GPS-aided, because there are two separate Kalman filters, one for GPS, and the other for INS, it is more easy to be implemented. Since the positioning accuracy of GPS is with long time stability, thus the divergent effect of INS can be improved with GPS-aided. On the other hand, since the positioning capability of INS is with short time accuracy, thus the jumped-characteristics or the lost track conditions due to receiver noise or antenna shielding effects can be improved by the GPS/INS structure. So the three dimensional navigation system by integrating GPS with INS can avoid the defects of each system, and raise the accuracy of positioning results.
Keywords: Global Positioning System,GPS;Inertial Navigation
System,INS;Loosely-Coupled Closed-Loop;Kalman Filter
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