23 accepted papers
We propose a novel walking control scheme based on the dynamics of the Linear Inverted Pendulum (LIP) model. The pattern generation incorporates a model of contact forces, enabling closed-loop control of the humanoid robot’s state, including the Center of Mass (CoM) position, velocity, and Zero Mome…
In this paper, we propose the multi-contact locomotion planning framework for humanoid robots that leverages the target contact selection considering its long-term preferability by reinforcement learning (RL) in optimization-based motion generation with feasibility constraints. It is difficult to pr
This work presents a novel method to keep stable contact and balance while stepping over partial footholds for biped humanoid robots with flat feet. We exploit plantar tactile feedback to detect the geometry of the terrain and reconstruct online the new supporting polygon after landing every step. P
Almost all (not to say all) existing humanoids have not been designed with the ability to change their end-effectors (head, feet and hands) on-the-fly. Inspired by the tool-changing mechanisms in robotics automation and manufacturing, we propose an end-effectors changer mechanism suitable to humanoi
On the one hand, cameras of conventional field-of-view usually considered in computer vision and robotics are very often modeled as a pinhole plus possibly a distortion model. On the other hand, there is a large variety of models for panoramic cameras. Many camera models have been proposed for fishe…
To enable humanoid robots to work robustly in confined environments, multi-contact motion that makes contacts not only at extremities, such as hands and feet, but also at intermediate areas of the limbs, such as knees and elbows, is essential. We develop a method to realize such whole-body multi-con
In this letter, we present a planning method considering regrasp and mobility for the manipulation problem of a long deformable object in an industrial scenario. The object is carried through designated rollers by a dual-arm robot in the presence of environmental constraints. The problem is formulat
We present a tele-operation control framework that (i) enhances the upper motion synchrony between a user and a robot using the minimum-jerk model coupled with a recursive least-square filter, and (ii) synchronizes the walking pace by predicting user's stepping frequency using motion capture data an
Multi-contact motion is important for humanoid robots to work in various environments. We propose a centroidal online trajectory generation and stabilization control for humanoid dynamic multi-contact motion. The proposed method features the drastic reduction of the computational cost by using previ
In this paper, we propose a trajectory planning framework for a robot that exploits a pre-computed database of end-effector trajectories as the guidance of optimization-based inverse kinematics. We constructed a reachable graph of a robot offline, which represents feasible end-effector paths with co…
In this letter, we propose an efficient and highly versatile loco-manipulation planning for humanoid robots. Loco-manipulation planning is a key technological brick enabling humanoid robots to autonomously perform object transportation by manipulating them. We formulate planning of the alternation a
In order for a humanoid robot to perform loco-manipulation such as moving an object while walking, it is necessary to account for sustained or alternating external forces other than ground-feet reaction, resulting from humanoid-object contact interactions. In this letter, we propose a bipedal contro
In this letter, we propose a multi-contact locomotion planning framework for a humanoid robot to traverse complex environments utilizing bilateral contact forces with reasonable computational time. We hypothesize that a bilateral contact can be approximated by a pair of surface contacts, and expand
In this paper we report the safety-oriented framework for controlling the torque in the case of robots with high reduction gears and having no joint torque feedback. This kind of robots suffer from high joint friction and low backdrivability, requiring high gains and integral feedback, which can be…
Deep Convolutional Neural Networks (CNNs) have been successfully deployed on robots for 6-DoF object pose estimation through visual perception. However, obtaining labeled data on a scale required for the supervised training of CNNs is a difficult task - exacerbated if the object is novel and a 3D mo…
In this letter, we present an observation scheme, with proven Lyapunov stability, for estimating a humanoid's floating base orientation. The idea is to use velocity aided attitude estimation, which requires to know the velocity of the system. This velocity can be obtained by taking into account the
In this letter, we propose a graph-search based multi-contact locomotion planning method for humanoid robots, focusing on the sustainability of contacts as its key feature. We introduce the idea of sustainable contact area, which represents the area on which contacts can be maintained during contact
The simulation of static friction, and especially the effect of stiction, is cumbersome to perform in discrete-time due to its discontinuity at zero velocity and its switching behavior. However, it is essential to achieve reliable simulations of friction to develop compliant torque control algorithm…
This letter introduces the humanoid robot HRP-5P, which stands for Humanoid Robotics Platform-5 Prototype. We have been developing the HRP series humanoid robots since 2000, and HRP-5P is the latest version of the HRP series as of 2018. It is developed as a prototype for our next generation humanoid
This paper focuses on a stabilization control for multi-contact motion which enables a humanoid robot to locomote by realizing dynamic contact transitions on non-flat environment. In the stabilization process of the multi-contact motion, the desired Zero-Moment Point (ZMP) is modified by the positio…
The dynamics of a humanoid robot cannot be correctly described independently from the external forces acting on it. These forces have to be reconstructed to enable the robot to control them or to compensate for them. Force sensors are usually used to measure these forces, but because of their cost,…
In order to accurately reach a target position while executing a task which imposes occlusion or constraints of the posture, a humanoid robot requires an adaptive locomotion system, which can comprehensively integrate localization, environmental mapping, global locomotion planning and local error co…
We propose a control framework for torque controlled humanoid robots that efficiently minimizes the tracking error in a Quadratic Programming (QP)formulated as multiobjective weighted tasks with constraints. It results in an optimal dynamically-feasible reference that can be tracked robustly, with e…