在太空任務之中，尤其是太空載具登陸的任務，姿態與位置資料對於太空船的動態控制而言是不可或缺的重要資訊。然而太空環境之下，一些常見的姿態資料的感測器如：磁力計、氣壓計與全球定位資訊系統(GPS)，皆是無法使用的。為此，如何建立一個在排除上述感測器的資料之下，進行定位與姿態估測的方法以完成太空任務致關重大。而在此需求下，即時建圖定位(SLAM)技術是其中一個可以加以參考並應用的技術。在外部感測器的輔助之下，例如：光達、雷達與視覺相機，即時進行資料的掃瞄並與全域地圖進行匹配，來推估自身所處之位置與姿態，來達成無磁力計、無氣壓計以及無GPS之下的定位與姿態估測。此外，本研究更進一步考慮到登陸點的選取與決策，藉由曲面重建的技術並利用平面的特性，搜尋出平坦、足夠廣闊與傾斜程度低的區域。而當姿態資料與登陸地點均具備的時候，太空載具便可依循該資料進行登陸任務。最終達成本研究－太空載具三圍姿態資料與登錄決策之目標。

For a spacecraft acting an astronautic mission, the information of attitude and position is doubtlessly necessary for controlling the motion of spacecraft, especially the mission of landing. However, in the environment of outer space, sensors for motion control in general aerial vehicle such as magnetometer, GPS and pressure altimeter are generally unavailable. With such requirement, the research of estimating attitude and position without those sensors is crucial. In order to reach such target, the technique of simultaneous localization and mapping (SLAM) can make contribution. With the use of sensors like LiDAR, Radar or vision, attitude and position can be estimated through registration of local scan data and global map data. Furthermore, apart from pose estimation and localization, the decision of landing zone is also considered in this research. With the application of surface reconstruction, the region satisfying the requirement of planar, sufficiently wide and lowly tilted can be searched out through the properties of plane. Once the state of motion and the landing zone are ready, the spacecraft may start the landing mission through above information, to achieve the target of spacecraft 6-DoF pose estimation and its application for unknown environment landing decision making.

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