Straight-Leg Walking Through Underconstrained Whole-Body Control
Abstract
We present an approach for achieving a natural, efficient gait on bipedal robots using straightened legs and toe-off. Our algorithm avoids complex height planning by allowing a whole-body controller to determine the straightest possible leg configuration at run-time. The controller solutions are biased towards a straight leg configuration by projecting leg joint angle objectives into the null-space of the other quadratic program motion objectives. To allow the legs to remain straight throughout the gait, toe-off was utilized to increase the kinematic reachability of the legs. The toe-off motion is achieved through underconstraining the foot position, allowing it to emerge naturally. We applied this approach of under-specifying the motion objectives to the Atlas humanoid, allowing it to walk over a variety of terrain. We present both experimental and simulation results and discuss performance limitations and potential improvements.
Cite
@article{arxiv.1709.03660,
title = {Straight-Leg Walking Through Underconstrained Whole-Body Control},
author = {Robert J. Griffin and Georg Wiedebach and Sylvain Bertrand and Alexander Leonessa and Jerry Pratt},
journal= {arXiv preprint arXiv:1709.03660},
year = {2019}
}
Comments
Submitted to 2018 IEEE International Conference on Robotics and Automation