Planning and execution of dynamic whole-body locomotion for a hydraulic quadruped on challenging terrain
Alexander W. Winkler, Carlos Mastalli, Ioannis Havoutis, Michele Focchi, Darwin G. Caldwell, Claudio Semini
Abstract
We present a framework for dynamic quadrupedal locomotion over challenging terrain, where the choice of appropriate footholds is crucial for the success of the behaviour. We build a model of the environment on-line and on-board using an efficient occupancy grid representation. We use Any-time-Repairing A* (ARA*) to search over a tree of possible actions, choose a rough body path and select the locally-best footholds accordingly. We run a n-step lookahead optimization of the body trajectory using a dynamic stability metric, the Zero Moment Point (ZMP), that generates natural dynamic whole-body motions. A combination of floating-base inverse dynamics and virtual model control accurately executes the desired motions on an actively compliant system. Experimental trials show that this framework allows us to traverse terrains at nearly 6 times the speed of our previous work, evaluated over the same set of trials.
BibTeX
@inproceedings{icra2015_planningandexecu,
title = {Planning and execution of dynamic whole-body locomotion for a hydraulic quadruped on challenging terrain},
author = {Alexander W. Winkler and Carlos Mastalli and Ioannis Havoutis and Michele Focchi and Darwin G. Caldwell and Claudio Semini},
booktitle = {ICRA 2015},
year = {2015}
}