中文摘要：

针对无人直升机的着陆过程，设计一种由同心圆和矩形组成的人工地标，并基于该地标给出一套无人直升机位姿参数估计的方法。该参数估计方法首先在图像中通过检测同心圆来确定目标区域，然后在区域内提取人工地标的特征点，最后利用特征点通过线性求解和非线性优化对无人直升机的位置和姿态参数进行解算。在多个高度位置进行了仿真试验，结果表明该方法能准确计算出无人直升机与降落平台的相对位姿参数，能够满足无人直升机降落过程中实时测量位姿参数的要求。

英文摘要：

In this paper, an artificial landmark comprising of the concentric circles and rectangles is designed aiming at the landing process of unmanned helicopter （UH）. And, a set of pose and position parameters estimation method for UH based on the landmark is presented. The given method first determines the target area in the image by detecting the concentric circles, then extracts the feature points of the land- mark in target area, and finally computes the position and pose parameters of UH through linear solution and nonlinear optimisation using fea- ture points. Simulation experiments are conducted for UH on several heights, the results clearly show that the method can accurately deter- mine the position and pose parameters of UH relative to the landing pad, and can meet the requirement of real-time position and pose parame- ters measurement when UH is landing.