Title
Multi-Layered Safety for Legged Robots via Control Barrier Functions and Model Predictive Control
Abstract
The problem of dynamic locomotion over rough terrain requires both accurate foot placement together with an emphasis on dynamic stability. Existing approaches to this problem prioritize immediate safe foot placement over longer term dynamic stability considerations, or relegate the coordination of foot placement and dynamic stability to heuristic methods. We propose a multi-layered locomotion framework that unifies Control Barrier Functions (CBFs) with Model Predictive Control (MPC) to simultaneously achieve safe foot placement and dynamic stability. Our approach incorporates CBF based safety constraints both in a low frequency kino-dynamic MPC formulation and a high frequency inverse dynamics tracking controller. This ensures that safety-critical execution is considered when optimizing locomotion over a longer horizon. We validate the proposed method in a 3D stepping-stone scenario in simulation and experimentally on the ANYmal quadruped platform.
Year
DOI
Venue
2021
10.1109/ICRA48506.2021.9561510
2021 IEEE INTERNATIONAL CONFERENCE ON ROBOTICS AND AUTOMATION (ICRA 2021)
DocType
ISSN
Citations 
Conference
1050-4729
0
PageRank 
References 
Authors
0.34
0
4
Name
Order
Citations
PageRank
Ruben Grandia1124.46
Andrew J. Taylor201.69
Aaron D. Ames31202136.68
Marco Hutter446058.00