Free Gait Planning of a Hexapod Robot for Uneven Terrain

doi:10.3901/JME.260089

Abstract

Abstract: The free gait planning of hexapod robots for uneven terrain greatly influences the motion and operation performance exploring complex scenarios. This research mainly focuses on the local terrain representation, dynamic and static stability evaluation, and free gait planning. Referencing the smooth motion mechanism of hexapods, inspiring by the discrete interaction between the foot and terrain, a description for the foot locations and an iterative integration strategy of terrain feature points are proposed, and then a local terrain representation method depending on footholds is established. By exploring the influences of support-footed polygons and single-footed workspace on robot stability, spatially static and temporally dynamic stability margins are proposed, which further establishes the stability evaluation method. Following the gait generation paradigm with feature plane switching, series of adjustment rules involving foothold locations and action sequences are formulated with referencing to feature planes, stability margins, and virtual queues, which is dedicated to establishing free gait planning method for uneven terrain. The experimental results show that a hexapod robot adopting proposed free gait planning method can generate suitable gaits to stably move on uneven test terrain.

Key words: hexapod robot, free gait planning, local terrain representation, stability evaluation, uneven terrain

CLC Number:

TG156

JIAO Xin, LI Manhong, ZHAO Zhengyang, ZHANG Yan, ZHANG Minglu. Free Gait Planning of a Hexapod Robot for Uneven Terrain[J]. Journal of Mechanical Engineering, 2026, 62(3): 340-352.

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