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Wheeled jumping robot by power modulation using twisted string lever mechanism



This study introduces a wheeled robot platform with jumping ability. To realize jump movement, a twisted string lever mechanism is used, which is characterized by its compactness and variable gear ratio. Based on robot modeling and parameter calculation, the twisted string actuator shows its advantage when applied to situations such as jumping of robots, where explosiveness of output force matters. In this study, a wheeled bipedal robot equipped with the twisted string actuator is designed and fabricated. It weighs 16.0 kg and can perform jumps when it encounters obstacles. The prototype can jump up to a stage with a maximum height of 1.0 m using electric power, which is approximately 1.5 times the height of its stretched legs.





为了实现跳跃运动, 采用了绞合线杠杆驱动机构, 其特点是结构紧凑, 传动比可变.




1. 所制造的轮式双足机器人重16.0公斤, 遇到障碍物时可以进行跳跃. 2. 原型机可以通过电力驱动跳到高度为1.0 m的台阶, 这大约是其腿完全伸展高度的1.5倍.

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Corresponding authors

Correspondence to Lei Jiang or Hong-tao Wang.

Additional information

Project supported by the Grant from Zhejiang Lab, China (No. 2019KE0AD01)


Xian-wei LIU designed the research. Xian-wei LIU and Yong-bin JIN processed the corresponding data. Xian-wei LIU wrote the first draft of the manuscript. Hong-tao WANG and Lei JIANG helped to organize the manuscript. Hong-tao WANG revised and edited the final version.

Conflict of interest

Xian-wei LIU, Yong-bin JIN, Lei JIANG, and Hong-tao WANG declare that they have no conflict of interest.

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Liu, Xw., Jin, Yb., Jiang, L. et al. Wheeled jumping robot by power modulation using twisted string lever mechanism. J. Zhejiang Univ. Sci. A 22, 767–776 (2021).

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Key words

  • Wheeled jumping robot
  • Twisted string lever mechanism
  • Non-linear transmission ratio

CLC number

  • TP24


  • 轮式跳跃机器人
  • 绞合线杠杆驱动
  • 非线性传动比