MOESM1 of Surmounting obstacles by arm maneuver for unmanned power shovel

Additional file 1. ODE simulation

Dynamic Lifting by Whole Body Motion of Humanoid Robots

International audienceA motion control method of lifting a heavy object up to a higher position with humanoid robots is developed. The key issue of lifting motion is how to reduce the load on humanoid arms in which low-power actuators are implemented. The use of singular postures of arms is well-known to avoid actuator saturation of the arms. By combining two different kinds of humanoid motions such as accelerating an object upward and sliding the body into under the object, we propose a method that enables to transit one singular posture of arms to another while lifting the object. Simulation results show the effectiveness of the proposed method for reducing the load on the arms. We realize a motion of lifting a heavy object dynamically with the humanoid robot HRP-2 through experiment

Lifting by Whole Body Motion of Humanoid

National audienceA motion control method of lifting a heavy object up to a higher position by humanoid robots is developed. Key issue of lifting motion is how to reduce the load on humanoid arms in which lowed power actuators are implemented. The use of singular postures of arms is well-known to avoid actuator saturation of the arms. We propose a motion planner based on optimization method with making better use of actuator’s characteristics. By combining two different kinds of humanoid motions such as accelerating an object upward and sliding the body into under the object, we show that the method enables to transit one singular posture of arms to another while lifting the object. We verify the effectiveness of the proposed method for reducing the load on the arms through simulation and experiment

Dynamic lifting motion for humanoid robots

Abstract-This paper describes a motion generation method for dynamic lifting by a humanoid robot. The proposed technique suggests the possibility of taking advantage of the whole body motion in order to facilitate the lifting movement. In particular, the idea is to perform a preliminary motion in order to generate a momentum which is instantaneously transferred to the object as an impulsive force. This allows the humanoid to lift up an object that could not be lifted up only by continuous force. However an impulsive force may make the humanoid unstable. Then, we propose to set the center of percussion (CoPn) of the whole system at the center of the support polygon of the humanoid when it lifts up the object. We also propose a design method of a preliminary motion of the humanoid that generates a sufficient momentum to lift up an object without any slip, tumble and hop of the whole system. The effectiveness of the proposed method is confirmed by simulation and experiment

Mobility of Humanoid Robots: Stepping over Large Obstacles Dynamically

International audience— Humanoid robots are getting increasingly attention in the robotics community, not only for the scientific challenge of the complex multibody system issues and mechatronic designs, but also due to their high mobility and versatility. Humanoid robots have the potential to navigate through complex environ-ments such as the standard living surrounding of humans. This is mainly due to the bipedal legged nature of the robotic system, which allows higher mobility than its wheeled counterpart. One of the advantages is that it can negotiate obstacles by stepping over them, which is the topic of the work presented in this paper. The main focus of this research is to investigate stepping over large obstacles. Previous work has reported on algorithms using quasi-static balancing, which resulted in somehow unnatural slow motions. This work however is focussing on stepping over larger obstacles in a fluent dynamic motion, using stability criteria on zero moment point instead of center of gravity. All the work is formulated in function of the elaborate HRP-2 humanoid research platform. In this paper a preliminary 2D study on stepping over leg trajectories and their dynamic implications on the overall stability are investigated. The paper discusses the implementation of the stepping over procedure in the overall dynamic motion generator, the implications on the kinematics and dynamics and finally the actual stepping over foot trajectory planner

Dynamic simulator for humanoids using constraint-based method with static friction

International audienceA dynamic simulator using constraint-based method is proposed. It is the extension of the formalism previously introduced by Ruspini and Khatib by including static and dynamic friction without friction cone discretization. The main contribution of the paper is in efficiently combining the operational space formulation of the multi-body dynamics in the contact space and solving for contact forces, including friction, using an iterative Gauss-Seidel approach. Comparing to existing work in this domain, we illustrate our method with scenarios involving humanoid in manipulation tasks while contacting with the environment; an experiment validates our results. Technical details that allow an efficient implementation and problems with future orientation to improve the simulator are also discussed. This work is aiming to be a potential module of the next OpenHRP simulator generation