Conference Paper

A walking pattern generator for biped robots on uneven terrains

Dept. of Comput. Sci., Univ. of North Carolina at Chapel Hill, Chapel Hill, NC, USA
DOI: 10.1109/IROS.2010.5653079 Conference: Intelligent Robots and Systems (IROS), 2010 IEEE/RSJ International Conference on
Source: IEEE Xplore


We present a new method to generate biped walking patterns for biped robots on uneven terrains. Our formulation uses a universal stability criterion that checks whether the resultant of the gravity wrench and the inertia wrench of a robot lies in the convex cone of the wrenches resulting from contacts between the robot and the environment. We present an algorithm to compute the feasible acceleration of the robot's CoM (center of mass) and use that algorithm to generate biped walking patterns. Our approach is more general and applicable to uneven terrains as compared with prior methods based on the ZMP (zero-moment point) criterion. We highlight its applications on some benchmarks.

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Available from: Ming C Lin, Apr 17, 2014
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    • "However, adjusting only hip or torso motion may not be enough to achieve the desired ZMP trajectory, and it may generate jerky motion [11]. The ZMP concept has been extended to wrench space in order to compute motions on non-planar terrains [23], [24]. The wrench-space approaches check whether the sum of wrenches applied on the robot is within the polyhedral convex cone of the convex wrench. "
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    • "The contact wrench naturally solves the redundancy issue, as its dimension is minimal (six). It was advocated as a generalization of ZMP in [2], along with a stability theorem, and applied to walking pattern generation on rough terrains [11] [12]. However, this theorem makes the same " sufficient friction " assumption as ZMP, which means the resulting criterion does not account for sliding and yaw rotations. "
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