Hopping locomotion has characteristics of isolated footholds, and powerful and explosive hopping force, which makes bio-inspired robots with hopping locomotion have the ability of jumping over obstacles and the environmental adaptability. In this paper, hopping robots are divided into four categories on the basis of research results in China and overseas: telescopic robots, articulated robots, wheeled & rolling robots and flexible robots. Combining with the current research about hopping robots, the characteristics of each categories are analyzed. The related key technologies are proposed. Finally, the development trends of hopping robots in future are predicted.
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