由於太空產業和半導體技術的擴展，這幾年在產業界和學術間促進了一種名為立方衛星之特定類型的奈米衛星的發展。立方衛星之飛行軟體扮演了極重要的角色，它負責定期的次系統健康資料檢查、模組之間的資料傳輸、通訊橋梁的控制和有效率的操作程序。除此之外，飛行軟體還必須能夠接收地面站所上傳的命令，檢查並且根據指令解碼然後執行。所有上述的內容必須結合在一起才能讓各個次系統或各酬載發揮其功用。

然而，運行於立方衛星的科學任務需求趨於複雜，因此設計出一套可靠的飛行軟體便成為一個關鍵的重點。整體的設計必須考量到許多層面來達到不同類型挑戰的需求。本論文旨在說明應用於立方衛星之可靠飛行軟體的實現及驗證。其中的討論包括飛行軟體的架構、操作模式的說明、模組化的設計、備用記憶體及弱化模式設計、異常狀況的處理方法、遠端更新飛行軟體的架構及自我設置的機制。論文的最後則是提到測試驗證的環境配置及方法，還有針對衛星電腦的中處理器效能、記憶體空間、儲存空間的優化及介面通訊的一些數據分析。

本論文所提及之軟體自我設置的機制可以藉由軟體自身根據情況來更新參數，而不是直接固定在程式碼中，如此一來可以幫助增加軟體的可靠度，並且可被使用至未來的立方衛星任務。最後，本研究所發展之飛行軟體的設計已實現於國立成功大學所開發的PHOENIX衛星，此立方衛星為歐盟QB50計畫中台灣唯一一顆衛星，並且預計將於2016年年底從國際太空站釋放。

The improvement of space technology and semiconductor industry have stimulated one specific type of nanosatellite called CubeSat in industry and universities in recent year. The flight software, which serves as a brain of the CubeSat, plays an important role in the system design. Its responsibility contains routine inspection of housekeeping data from other subsystems, data transmission between each module, control of the communication throughput, and effective operation technique. Also, the flight software is required to receive the command sent from the ground station, decodes the telecommand into specific format, and then executes it according to the instruction. All of these works are combined together to make each subsystem or payload perform the desired function.

As the requirement of the science mission becomes increasingly complicated, to design a reliable flight software becomes a key point of a successful satellite mission. The overall system design must consider many aspects to meet the demand of different kind of challenges. This thesis aims to discuss the implementation and verification of reliable flight software for CubeSats. The scope includes the architecture design of flight software, detailed operation mode, modular design, redundant memory allocation, crippled mode, anomaly handling, in-orbit software update, and self-configuration mechanism. Moreover, the verification environment and method will be mentioned, followed by the performance analysis on CPU, RAM, storage, and I2C protocol of the on board computer.

More importantly, an innovative design with self-configurable mechanism to help increase the reliability of the flight software is developed. The proposed software design has been implemented in the PHOENIX nanosatellite which is developed by National Cheng Kung University, the only Taiwanese satellite in the QB50 mission, and is scheduled to be released into the space from the International Space Station at the end of 2016.

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