近年來，隨著智慧城市的蓬勃發展，車載導航(Land Vehicular Navigation, LVN)的發展備受矚目，受益於慣性導航系統(Inertial Navigation System, INS)與全球衛星導航系統(Global Navigation Satellite System, GNSS)的互補特性，INS/GNSS整合導航系統在導航領域中得到廣泛的應用。在市面上，搭載不同等級感測器的商用整合導航系統數不勝數，然而，在商用導航系統上難以實現完全的客製化，進而導致在使用者渴望達到特定精度的同時，需要付出多餘的成本，因此，基於此考量，本文提出且實現了以硬體整合框架與基於鬆耦合架構之多感測器融合演算法組成之整合導航系統架構，以滿足整合導航系統模組化之需求。
　　在整合導航系統中，時間同步的正確性是追求高導航精度之關鍵，由於時間同步之即時運算需求，本文基於嵌入式系統，並採用衛星接收機所提供之每秒脈波訊號(Pulse-Per-Second signal, PPS)，以提出一種可行的時間同步方案；另一方面，在開發時間同步方法的同時，檢驗測試方法的可行性是不可或缺的過程，為此需求，本文提出了一種基於互相關(Cross-correlation)函數的時間同步檢驗方法。
　　在導航過程中，需要在多感測器整合演算法的開端，先確定初始訊息，包含了位置、速度和姿態。由於本文整合之導航系統採用了高規格戰術等級之IMU，其內含有光纖陀螺儀 (Fiber Optic Gyroscope, FOG)，可以根據法向重力和地球自轉速率的測量向量在靜態下進行初始對準。因此，本文建立了一種初始對準機制。值得注意的是，粗對準通過移動窗口之Sinc濾波器和穩定性檢查機制進行優化，以減少導致粗對準誤差之外部干擾，例如：人為因素與引擎震動，再者，本文基於EKF設計了一種可行的精對準，以提高初始姿態的準確性，同時估計整個整合導航系統之導航狀態。
　　為了驗證所提出的初始對準機制和組合導航系統的可行性，本研究在陸地車輛上進行了三個實驗。根據第一個實驗的性能分析，藉由提出的優化之粗對準架構，滾轉、俯仰和航向誤差可分別降低33%、33%、74.8%。接下來，在第二次實驗中，藉由精密對準，滾轉、俯仰和航向的誤差降低能夠達到 93.6%、44.4%、77.4%。在第三次實驗中，對於 IMU500 和 IMU1000，初始姿態的準確性通過精細對準也有顯著地提高，此外，為強調所設計之整合導航系統架構之完全客製化特性，基於所提出之架構，使用四個具有不同等級IMU的整合導航系統進行了多環境實驗，在衛星訊號脫落區域，與理論漂移誤差相比，所有測試系統的最大誤差均小於理論值。證明了所提出的整合導航系統方案之可行性。

In recent years, with the trend of smart city, the development of land vehicular navigation has received lots of attention. Benefiting from the complementary characteristics between INS and GNSS, the INS/GNSS integrated navigation system is widely utilized in navigation applications. On the market, there are countless commercial integrated navigation systems which are equipped with different grade sensors. Nevertheless, the full customization for the navigation system is difficult to reach in the commercial system. It often leads to extra cost when the users eager to achieve specified accuracy. Therefore, on account of this issue, an integrated scheme, which is composed of hardware integration structure and multi-sensor fusion algorithm based on the LC scheme, for the integrated navigation system which can achieve the fully customized requirement is proposed and implemented in this thesis.
In the integrated navigation system, the correctness of time synchronization is a critical key for the navigation accuracy. Since time synchronization is required to conduct in real-time, an embedded system is utilized. On the basis of the embedded system, a feasible time synchronization method which adopts the Pulse Per Second (PPS) signal is proposed in this thesis. On the other hand, in the development of time synchronization method, it is essential to inspect the feasibility of the testing methods. Hence, based on the cross-correlation function, a time delay estimation method for IMU time stamp is presented in this thesis.
Before the integration of sensors, initial information such as position, velocity, and attitudes should be determined in the process of navigation. Owing to the adopted high-end tactical IMU, the initial alignment can be conducted in the static state based on the measurement vectors from normal gravity and Earth rotation rate. Therefore, a mechanism for initial alignment is built in this thesis. It is noted that the coarse alignment is optimized through a windowed Sinc filter and stability checking to reduce outer interference which causes faulty in coarse alignment. Furthermore, a workable fine alignment is designed based on EKF to improve the accuracy of initial attitudes and estimate the navigation states for the whole integrated system in the meanwhile.
To verify the proposed initial alignment mechanism and the feasibility of the integrated navigation system, three experiments are conducted with a land vehicle in this research. According to the analysis of performance of the first experiment, with the proposed coarse alignment method, the errors of roll, pitch, and heading can reduce 33%, 33%, 74.8% respectively. Next, in the second experiment, with fine alignment, the error reduction of roll, pitch, and heading is able to reach 93.6%, 44.4%, 77.4%. Also, in the third experiment, for IMU500 and IMU1000, the accuracy of initial attitudes improves significantly through fine alignment. To emphasize the fully customized feature of the designed scheme, four integrated navigation systems which are equipped with different grade IMUs based on the proposed scheme are taken to conduct the third experiment for multiple environments simultaneously. In comparison with the theoretical drifting errors, the maximum errors of all testing systems are smaller than the theoretical one in GNSS outage environments. It proves that the feasibility of the proposed scheme for the integrated navigation system.

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