Research on Motion Planning of Hexapod Robot Based on DRL and Free Gait

doi:10.16182/j.issn1004731x.joss.22-1220

Abstract

Abstract:

To improve the passability and the motion performance of the hexapod robot in the unstructured environment, a multi-contact motion planning algorithm based on DRL and free gait planner is proposed. Firstly, the free gait planner obtains the reachable footholds under the target state and outputs the optimal gait sequence. The center of mass motion policy of the hexapod robot in the randomly generated plum blossom pile environment is obtained by using deep reinforcement learning training. To ensure the reachability between adjacent states of the robot in motion, the state transition feasibility model is used to judge the state transition feasibility. Finally, the foothold planning of the hexapod robot in the plum blossom pile environment with gullies of different widths is realized. Simulation and physical experiments show that the multi-contact motion planning algorithm can make the robot reach the target area quickly and smoothly from the starting point, and automatically adjust the gait pattern to deal with the randomly distributed plum blossom piles in different environments.

Key words: hexapod robot, free gait, DRL, multi-contact motion planning, unstructured environment

CLC Number:

TP242.6

Wang Xinpeng, Fu Huiqiao, Deng Guizhou, Tang Kaiqiang, Chen Chunlin, Liu Canghai. Research on Motion Planning of Hexapod Robot Based on DRL and Free Gait[J]. Journal of System Simulation, 2024, 36(2): 373-384.

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i	α_i /(°)	a_i	θ_i
1	90	l₁	θ₁
2	0	l₂	θ₂
3	0	l₃	θ₃

参数	基节	髋关节	膝关节
长度/mm	60	120	145.8
转角范围/(°)	[-45, 45]	[0, 45]	[-135, -90]

环境	沟壑宽度
I	0
II	100
III	150

环境	平均回合步数	平均回合成功率/%
I	25	100
II	31	98
III	64	52

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