Dynamic motion of quadrupedal robots on challenging terrain: a kinodynamic optimization approach

  • Qi LI 1,2 ,
  • Lei DING 1,2 ,
  • Xin LUO , 3
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  • 1. Engineering Research Center of Hubei Province for Clothing Information, Wuhan 430200, China
  • 2. School of Computer Science and Artificial Intelligence, Wuhan Textile University, Wuhan 430200, China
  • 3. State Key Laboratory of Digital Manufacturing Equipment and Technology, Huazhong University of Science and Technology, Wuhan 430074, China
mexinluo@hust.edu.cn

Received date: 11 Dec 2023

Accepted date: 21 Mar 2024

Published date: 15 Jun 2024

Copyright

2024 Higher Education Press

Abstract

The dynamic motion of quadrupedal robots on challenging terrain generally requires elaborate spatial–temporal kinodynamic motion planning and accurate control at higher refresh rate in comparison with regular terrain. However, conventional quadrupedal robots usually generate relatively coarse planning and employ motion replanning or reactive strategies to handle terrain irregularities. The resultant complex and computation-intensive controller may lead to nonoptimal motions or the breaking of locomotion rhythm. In this paper, a kinodynamic optimization approach is presented. To generate long-horizon optimal predictions of the kinematic and dynamic behavior of the quadruped robot on challenging terrain, we formulate motion planning as an optimization problem; jointly treat the foot’s locations, contact forces, and torso motions as decision variables; combine smooth motion and minimal energy consumption as the objective function; and explicitly represent feasible foothold region and friction constraints based on terrain information. To track the generated motions accurately and stably, we employ a whole-body controller to compute reference position and velocity commands, which are fed forward to joint controllers of the robot’s legs. We verify the effectiveness of the developed approach through simulation and on a physical quadruped robot testbed. Results show that the quadruped robot can successfully traverse a 30° slope and 43% of nominal leg length high step while maintaining the rhythm of dynamic trot gait.

Cite this article

Qi LI , Lei DING , Xin LUO . Dynamic motion of quadrupedal robots on challenging terrain: a kinodynamic optimization approach[J]. Frontiers of Mechanical Engineering, 2024 , 19(3) : 20 . DOI: 10.1007/s11465-024-0791-5

Acknowledgements

This work was supported by the Foundation of Engineering Research Center of Hubei Province for Clothing Information, China (Grant No. 2023HBCI05), the Hubei Provincial Natural Science Foundation General Program, China (Grant No. 2022CFB563), and the Hubei Key Laboratory for New Textile Materials and Applications, Wuhan Textile University, China (Grant No. FZXCL202311).

Conflict of Interest

The authors declare that they have no conflict of interest.
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