Navigating in unfamiliar geometric terrain
Navigating in unfamiliar geometric terrain
复制标题
在不熟悉的几何地形中导航
DOI:
10.1145/103418.103419
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发表时间:
1991
期刊:
影响因子:
--
通讯作者:
B. Schieber
中科院分区:
文献类型:
--
作者:
Avrim Blum;P. Raghavan;B. Schieber
Consider a robot that has to travel from a start location $s$ to a target $t$ in an environment with opaque obstacles that lie in its way. The robot always knows its current absolute position and that of the target. It does not, however, know the positions and extents of the obstacles in advance; rather, it finds out about obstacles as it encounters them. We compare the distance walked by the robot in going from $s$ to $t$ to the length of the shortest (obstacle-free) path between $s$ and $t$ in the scene. We describe and analyze robot strategies that minimize this ratio for different kinds of scenes. In particular, we consider the cases of rectangular obstacles aligned with the axes, rectangular obstacles in more general orientations, and wider classes of convex bodies both in two and three dimensions. For many of these situations, our algorithms are optimal up to constant factors. We study scenes with nonconvex obstacles, which are related to the study of maze traversal. We also show scenes where randomized algorithms are provably better than deterministic algorithms.