立方衛星在最近幾年有蓬勃的發展，執行的任務越來越多樣化，隨著相關技術的成熟，立方衛星已具有高精確度姿態控制的能力。為了確保任務成功執行並儘可能地延長執行時間，應為立方衛星上高靈敏性的光感測元件進行一定程度的保護。透過對姿態精確的控制可以避免這類型感測元件與太陽或類似的發光體直射，以達到保護效果。另一方面，立方衛星上還有一類型的儀器需要時刻保持特定方向才能維持正常運作，例如指向性天線抑或是地球感測器，這類型儀器的操作同樣需仰賴姿態控制的能力。綜上所述，立方衛星在做姿態的控制時須同時考量各儀器在指向上的要求，本論文探討在此種限制下該如何對姿態控制的控制法則做出修正。
本研究將以修正式羅德里格參數作為描述姿態的主要方式，適當利用此參數的非唯一性將能夠在最低維度並且避開奇異點的情況下描述所有姿態，並以一對數懲罰函數來描述指向性的姿態限制，根據李亞普諾夫的穩定理論來推導出控制法則，最後提出一套控制流程來應對單一控制法則在應用上的限制。

In recent years, CubeSat has become a popular platform to demonstrate state-of-the-art technology in various fields as it is cheaper and can be launched in a short time compared to a regular satellite. Thanks to the rapid development of technology, CubeSat is now able to meet the highly accurate pointing requirement. To ensure the success of the mission and prolong the lifetime of the CubeSat, it is necessary to protect the sensitive instruments on the CubeSat. By controlling the attitude deliberately, we can have those sensors to avoid direct exposure to very bright celestial objects. On the other hand, there is another kind of onboard instruments which should point toward a certain direction in order to function properly. Therefore, implementing the attitude maneuver of the CubeSat is actually subject to several kinds of pointing constraints.
In this thesis, we use the modified Rodrigues parameters (MRPs) as the main attitude representations. MRPs are able to describe all the orientations with the lowest dimension and avoid encountering any singularity by taking advantage of the non-uniqueness properly. The attitude constraints are expressed in the logarithmic barrier potential functions so it is easy to combine them with the Lyapunov functions which are used to generate the unconstrained control law. Finally, we discuss the issue of the control law under the attitude tracking scenario and propose a control scheme to deal with it.

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