A Versatile and Efficient Pattern Generator for Generalized Legged Locomotion

Justin Carpentier (1) , Steve Tonneau (1) , Maximilien Naveau (1) , Olivier Stasse (1) , Nicolas Mansard (1)

1 LAAS-GEPETTO - Équipe Mouvement des Systèmes Anthropomorphes

This paper presents a generic and efficient approach to generate dynamically consistent motions for under-actuated systems like humanoid or quadruped robots. The main contribution is a walking pattern generator, that is able to compute a stable trajectory of the center of mass of the robot along with the angular momentum, for any given configuration of contacts (e.g. on uneven, sloppy or slippery terrain, or with closed-gripper). Unlike previously proposed method, our solver is efficient enough to be applied as a model-predictive controller. We then propose to integrate this versatile walking pattern generator in a complete application: an acyclic contact planner is first used to automatically compute the contact sequence from a 3D model of the environment and a desired final posture; a stable walking pattern is then computed by the proposed solver; a dynamically-stable whole-body trajectory is finally obtained using a second-order hierarchical inverse kinematics. The implementation of the whole pipeline is real-time. The interest of the method is demonstrated by real experiments on the HRP-2 robot, by performing long-step walking and by climbing a staircase with handrail support.

Mots clés: Humanoid Robot; Legged locomotion; Motion Planning; Optimal Control; Whole Body Locomotion

Domaines: Automatique / Robotique; Systèmes dynamiques [math.DS]; Optimisation et contrôle [math.OC]

Justin Carpentier, Steve Tonneau, Maximilien Naveau, Olivier Stasse, Nicolas Mansard. A Versatile and Efficient Pattern Generator for Generalized Legged Locomotion. 2015. ⟨hal-01203507v1⟩