仿人机器人动态步行控制综述

综述了仿人机器人动态步行的研究历史和研究现状。归纳了动态步行的特点,分析了动态步行稳定性判定方法,介绍了基于ZMP的姿态稳定判据和基于庞加莱映射（Poincaré Map）的步态稳定判据。总结了仿人机器人学习适应复杂地面环境步行的方法,概述了动态步行控制实现的典型解决方案,指出了动态步行控制中待解决的问题,并探讨了未来的发展方向。     

任务导向的仿人机器人体系结构设计

从仿人机器人任务实现过程出发,提出了一种基于任务的分层混合式仿人机器人体系结构。在该体系结构下,多个agent分别被用来模拟人的各主要器官的功能,并模仿人类的行为方式实现了任务实现过程中的三个主要部分:人机交互、导航和对象操作。该体系结构对于高智能水平的仿人机器人的研究和开发具有重要意义。     

Natural human–robot musical interaction: understanding the music conductor gestures by using the WB-4 inertial measurement system

This paper presents an inertial measurement unit-based human gesture recognition system for a robot instrument player to understand the instructions dictated by an orchestra conductor and accordingly adapt its musical performance. It is an extension of our previous publications on natural human–robot musical interaction. With this system, the robot can understand the real-time variations in musical parameters dictated by the conductor’s movements, adding expression to its performance while being synchronized with all the other human partner musicians. The enhanced interaction ability would obviously lead to an improvement of the overall live performance, but also allow the partner musicians, as well as the conductor, to better appreciate a joint musical performance, thanks to the complete naturalness of the interaction.     

Designing LED lights for a robot to communicate gaze

ABSTRACT

Eye gaze is considered to be a particularly important non-verbal communication cue. Gaze research is also becoming a hot topic in human–robot interaction (HRI). However, research on social eye gaze for HRI focuses mainly on human-like robots. There remains a lack of methods for functional robots, which are constrained in appearance, to show gaze-like behavior. In this work, we investigate how we can implement gaze behavior in functional robots to assist humans in reading their intent. We explore design implications based on LED lights as we consider LEDs to be easily installed in most robots while not introducing features that are too human-like (to prevent users from having high expectations towards the robots). In this paper, we first developed a design interface that allows designers to freely test different parameter settings for an LED-based gaze display for a Roomba robot. We summarized design principles for well simulating LED-based gazes. Our suggested design is further evaluated by a large group of participants with regard to their perception and interpretation of the robot's behaviors. On the basis of the findings, we finally offer a set of design implications that can be beneficial to HRI and HCI researchers.     

Human‐robot collaborative site‐specific sprayer

Spraying pesticides is a key element of agriculture worldwide, since 30% to 35% of crop losses can be prevented when harmful insects and diseases are eliminated by applying pesticides. Site‐specific spraying can help reduce pesticide application; however, target detection is limited due to the complex agricultural environment. This paper presents a human‐robot collaborative sprayer designed for site‐specific targeted spraying. The robotic sprayer platform, the framework, and tools for the robotic sprayer to collaborate with a remote human operator for the target detection and spraying tasks are detailed. An experiment to evaluate the elements of the collaborative human‐robot framework working in sync was designed, implemented, and evaluated. The collaborative spraying system shows a 50% reduction of sprayed material. The experiment also proves the feasibility of human‐robot collaboration for the complex task of spraying specific targets considering both the True Positive (TP) and False Positive (FP) rates.     

Safe and efficient motion planning of multiple mobile robots based on artificial potential for human behavior and robot congestion

In order for robots to exist together with humans, safety for the humans has to be strictly ensured. On the other hand, safety might decrease working efficiency of robots. Namely, this is a trade-off problem between human safety and robot efficiency in a field of human–robot interaction. For this problem, we propose a novel motion planning technique of multiple mobile robots. Two artificial potentials are presented for generating repulsive force. The first potential is provided for humans. The von Mises distribution is used to consider the behavioral property of humans. The second potential is provided for the robots. The Kernel density estimation is used to consider the global robot congestion. Through simulation experiments, the effectiveness of the behavior and congestion potentials of the motion planning technique for human safety and robot efficiency is discussed. Moreover, a sensing system for humans in a real environment is developed. From experimental results, the significance of the behavior potential based on the actual humans is discussed. For the coexistence of humans and robots, it is important to evaluate a mutual influence between them. For this purpose, a virtual space is built using projection mapping. Finally, the effectiveness of the motion planning technique for the human–robot interaction is discussed from the point of view of not only robots but also humans.     

Fuzzy-based-admittance controller for safe natural human–robot interaction

ABSTRACT

In recent years, a great amount of research on physical human–robot interaction has been conducted, and mainly concentrated on safety issues to minimize the risk of accidents to the operator during the cooperation between human and robot. Unfortunately, the identification of inertia and damping matrices in the dynamic admittance model is time-consuming, which is still an open problem of previous admittance controllers. Additionally, the natural cooperation is that cooperative movements are implemented in every degree of freedom in space, which is rarely concerned while it is important to implement more complex cooperative movements, and to help operator feels naturally during the cooperation. This paper presents an alternative admittance controller based on inference mechanism of fuzzy logic to eliminate the identification of inertia and damping matrices during the process of controller formulation in which the end-effector’s velocity is adaptively adjusted via external wrench (force/torque measured by a sensor mounted on end-effector) and power transmitted by the robot. Moreover, the proposed controller also considers end-effector’s full DOF to guarantee the natural human–robot interaction. The fuzzy-admittance controller is evaluated by an experimental set-up of teaching task using 6-DOF manipulator in which manipulator moves passively via the human impact on real-time force/torque sensor mounted on end-effector.     

Realizing whole-body tactile interactions with a self-organizing,multi-modal artificial skin on a humanoid robot

In this paper, we present a new approach to realize whole-body tactile interactions with a self-organizing, multi-modal artificial skin on a humanoid robot. We, therefore, equipped the whole upper body of the humanoid HRP-2 with various patches of CellulARSkin – a modular artificial skin. In order to automatically handle a potentially high number of tactile sensor cells and motors units, the robot uses open-loop exploration motions, and distributed accelerometers in the artificial skin cells, to acquire its self-centered sensory-motor knowledge. This body self-knowledge is then utilized to transfer multi-modal tactile stimulations into reactive body motions. Tactile events provide feedback on changes of contact on the whole-body surface. We demonstrate the feasibility of our approach on a humanoid, here HRP-2, grasping large and unknown objects only via tactile feedback. Kinesthetically taught grasping trajectories, are reactively adapted to the size and stiffness of different test objects. Our paper contributes the first realization of a self-organizing tactile sensor-behavior mapping on a full-sized humanoid robot, enabling a position controlled robot to compliantly handle objects.     

Robonaut: a robot designed to work with humans in space

The Robotics Technology Branch at the NASA Johnson Space Center is developing robotic systems to assist astronauts in space. One such system, Robonaut, is a humanoid robot with the dexterity approaching that of a suited astronaut. Robonaut currently has two dexterous arms and hands, a three degree-of-freedom articulating waist, and a two degree-of-freedom neck used as a camera and sensor platform. In contrast to other space manipulator systems, Robonaut is designed to work within existing corridors and use the same tools as space walking astronauts. Robonaut is envisioned as working with astronauts, both autonomously and by teleoperation, performing a variety of tasks including, routine maintenance, setting up and breaking down worksites, assisting crew members while outside of spacecraft, and serving in a rapid response capacity.     

Effect of practice on similar and dissimilar skills in patient transfer through training with a robot patient

With the number of hospital stays increasing, nurses require more training to handle a variety of patients. However, time for training in nursing schools is limited, and students lack the opportunity to practice on a diverse variety of patients. Using a robot to simulate actual patients, this study observes the learning transfer effect of practice on practice-similar and practice-dissimilar skills from one patient to another, and investigates which types of practice suit which kinds of training. An experiment was conducted by administering a pre-test, practice, a post-test, and a transfer test to two groups (N?=?8), each with different practice-related skills. The evaluation used a checklist covering required skills that were either similar or dissimilar across groups, depending on their practice. The effect of practice can be observed through a comparison of skills similar to one group but dissimilar to the other. The results show that practice facilitates learning transfer on similar skills but not, or to a lesser degree, on dissimilar skills. Furthermore, if skills needed to handle given symptoms are unfamiliar or inaccessible to students, practice related to those symptoms should be emphasized through simulated training with robots.     

仿人机器人上楼梯行走稳定性研究

针对仿人机器人上楼梯行走稳定性问题,进行了步态规划、稳定区域和稳定裕量的计算、控制策略等关键技术的研究。通过仿真,得到稳定行走姿态变化情况及各关节参数,为研究实时控制提供了依据。     

双足机器人稳定行走的仿人预测控制研究

针对双足机器人的稳定行走,提出了一种新的仿人预测控制在线步行模式生成方法。把期望零力矩点（ZMP）分解成离线规划好的参考ZMP和实时变化的可变ZMP之和,通过预测控制和其逆系统共同作用对质心运动进行控制,从而生成具有自适应性的步行模式。但单一的预测控制系统对诸如矩形齿状扰动的可变ZMP的跟踪存在较大的误差,结合仿人智能控制对误差的强抑制能力,设计了与预测控制相结合的仿人预测控制系统。仿真实验验证对矩形齿状扰动的可变ZMP,仿人预测系统也能实现较好的跟踪。     

Velocity observer-based iterative learning control for robot manipulators

This article addresses the problem of designing an iterative learning control for trajectory tracking of rigid robot manipulators subject to external disturbances, and performing repetitive tasks, without using the velocity measurement. For solving this problem, a velocity observer having an iterative form is proposed to reconstruct the velocity signal in the control laws. Under assumptions that the disturbances are repetitive and the velocities are bounded, it has been shown that the whole control system (robot plus controller plus observer) is asymptotically stable and the observation error is globally asymptotically stable, over the whole finite time-interval when the iteration number tends to infinity. This proof is based upon the use of a Lyapunov-like positive definite sequence, which is shown to be monotonically decreasing under the proposed observer–controller schemes.     

仿人机器人实时路径规划方法研究

为了使仿人机器人在人类生活环境中自由行走,将仿人机器人的动作离散化为指定的动作,将状态空间离散化为网格,利用立体视觉和平面提取方法建立环境地图,将仿人机器人的轮廓简化为双圆柱模型进行避障检测,最终在环境地图中搜寻代价最小的一系列可行的动作作为路径,通过仿真实验验证了方法的有效性。     

Balancing control of a bicycle-riding humanoid robot with center of gravity estimation

In this research, a miniaturized humanoid robot is constructed to ride and pedal a bicycle of comparable size. The design of the controller for the robot to balance and steer the bicycle using the handlebar is of particular interest. The controller possesses the capability to estimate the uncertain center of gravity of the robot-bicycle system and then incorporate such an estimation to enhance control performance. A general control framework which can achieve asymptotic stability under uncertain measurement biases is adopted for controller design. Using the framework, the stability of the control system is analytically guaranteed and its control parameters can be determined in a systematic manner. Both simulations and experiments verify that the proposed controller can automatically counteract the mass imbalance in the robot-bicycle system and allow it to perform straight-line steering without using camera visual feedback.     

Visual servo walking control for humanoids with finite-time convergence and smooth robot velocities

In this paper, we address the problem of humanoid locomotion guided from information of a monocular camera. The goal of the robot is to reach a desired location defined in terms of a target image, i.e., a positioning task. The proposed approach allows us to introduce a desired time to complete the positioning task, which is advantageous in contrast to the classical exponential convergence. In particular, finite-time convergence is achieved while generating smooth robot velocities and considering the omnidirectional waking capability of the robot. In addition, we propose a hierarchical task-based control scheme, which can simultaneously handle the visual positioning and the obstacle avoidance tasks without affecting the desired time of convergence. The controller is able to activate or inactivate the obstacle avoidance task without generating discontinuous velocity references while the humanoid is walking. Stability of the closed loop for the two task-based control is demonstrated theoretically even during the transitions between the tasks. The proposed approach is generic in the sense that different visual control schemes are supported. We evaluate a homography-based visual servoing for position-based and image-based modalities, as well as for eye-in-hand and eye-to-hand configurations. The experimental evaluation is performed with the humanoid robot NAO.     

基于一级倒立摆模型仿人机器人控制算法研究

针对仿人机器人步态行走不稳定的问题,以倒立摆为控制对象,建立仿人机器人步态行走数学模型。以仿人机器人姿态角和位移建立双闭环控制系统,采用PID控制算法对仿人机器人姿态角和位移进行调节。以19自由度仿人机器人进行实验验证,表明了所采用仿人机器人步态行走系统PID控制算法的正确性及高精确度。系统响应稳定,超调<0.3%,调节时间<0.2 s,关节输出相对误差最大值为2.25%,可实现仿人机器人稳定的步态行走。     

仿人机器人步态规划反馈控制研究综述

仿人机器人步行稳定性是机器人领域重要研究内容之一。介绍了仿人机器人常用的步态规划方法,划分为非反馈式和反馈式的两种步态规划算法。总结了反馈式步态规划主要研究的内容,并以世界著名Asimo、HRP、KHR和Darmstad仿人机器人为例,描述仿人机器人具体反馈控制方法和过程。探讨了仿人机器人步态反馈控制中有待研究的内容。     

UAV-guided navigation for ground robot tele-operation in a military reconnaissance environment

A military reconnaissance environment was simulated to examine the performance of ground robotics operators who were instructed to utilise streaming video from an unmanned aerial vehicle (UAV) to navigate his/her ground robot to the locations of the targets. The effects of participants' spatial ability on their performance and workloadwere also investigated. Results showed that participants' overall performance (speed and accuracy) was better when she/he had access to images from larger UAVs with fixed orientations, compared with other UAV conditions (baseline- no UAV, micro air vehicle and UAV with orbiting views). Participants experienced the highest workload when the UAV was orbiting. Those individuals with higher spatial ability performed significantly better and reported less workload than those with lower spatial ability.

The results of the current study will further understanding of ground robot operators' target search performance based on streaming video from UAVs. The results will also facilitate the implementation of ground/air robots in military environments and will be useful to the future military system design and training community.