基于似人特性的拟人臂机器人自主抓取动作规划

针对拟人臂机器人在家庭环境中的自主抓取任务,提出了一种强调运动姿态似人特性的拟人臂动作的规划方法.该方法分为两个部分,构型规划和运动规划,构型规划基于人体工程学中广泛使用的快速上肢评估准则评价机器人运动姿态的似人特性,并在此基础上以机器人末端传速速率最优为目标规划机器人运动过程中的关键构型.运动规划结合了Fitts定律和似人运动模型规划了机器人末端的空间轨迹.本文最后以Motoman SDA10D拟人双臂机器人和Mitsubishi PA10机器人为例,具体介绍了该方法的应用和规划的结果,规划结果证明了本方法的可行性和有效性.     

机器人实时运动规划问题

<正> 机器人在自动装配、航空、航天及军事领域起着越来越重要的作用.在许多应用场合,要求机器人在未知环境中能够自动地生成非碰撞路径,即运动规划问题.在这种情况下,必须用传感器来获得环境中的信息.因此,要求机器人能实时处理运动规划问题.运动规划的目的是在复杂环境中寻找避碰路径.运动规划问题主要包括下面几个方面:姿态空间机器人、目标及障碍物的表达计算姿态空间障碍物运动规划的方法搜索方法运动的局部优化1 工作空间和姿态空间工作空间是指机器人目标和障碍物所在的物理空间、Lozano P(?)rez在1979—1981年提出了姿态空间的概念,许多学者也对该问题进行了深入的研究.一个物体或障碍物的姿态是说明目标或机器人的不相关参数的集合.目标或机器人的所有可能姿态的集合,即姿态空间表达了物体的所有可能的运动.姿态空间的概念在运动规划问题中起着举足轻重的作用.这样,机器人在工作空间的运动规划问题等价于在姿态空间中的运动规     

遥操作护理机器人系统的操作者姿态解算方法研究

设计了一种遥操作护理机器人系统,为实现从端同构式机器人的随动运动控制,对主端操作者人体姿态解算方法进行了研究.首先,构建由惯性传感单元构成的动作捕捉系统,对用作从端机器人动作指令的操作者人体姿态信息进行采集,采用四元数法对人体运动原始数据进行初步求解.其次,将四元数法得到的姿态数据解算成依据仿人结构设计的护理机器人各关节运动的目标姿态角,实现人体姿态到机器人动作的同构性映射.最后,为验证本文所提姿态解算方法的性能,设计了操作者控制护理机器人完成递送和拿取药瓶动作的实验.结果表明,本文姿态解算方法的解算性能与参考系统基本相同;在操作者动作姿态快速变化的时间段,系统仍可获得较高精度的目标姿态数据,其误差在动态条件下依旧能保持在2%以下;护理机器人可较好地实时复现操作者的人体动作.本文方法能满足机器人进行一般护理作业时对人体姿态数据处理的快速性和准确性要求.     

关节型机器人的似人操作构型规划

对关节型机器人的操作构型进行规划时,本文提出了一种新的规划方法,它结合了似人评估准则和机器人传速特性优化的概念,可实现有最大末端传速特性的操作,同时与人类手臂操作的特点最为相似.该方法首先利用应用人体工程学中的快速上肢评价准则(RULA)对机器人的操作空间进行划分,然后在各子空间内最大化机器人末端沿指定方向的传速速率.最终选定一个最符合人类操作特性又同时满足操作任务的机器人操作构型.通过在2自由度平面机器人和7自由度拟人机械臂上的规划实验进一步展示了本方法的使用,规划结果验证了其有效性.     

基于视觉模型成像的六轴焊接机器人关节运动姿态规划研究

由于传统的六轴焊接机器人关节运动姿态规划方法存在关节运动姿态规划精度低、规划时间长的问题,提出基于视觉模型成像的六轴焊接机器人关节运动姿态规划方法.计算摄像机与机器人坐标关系,并通过图像雅克比矩阵,确定图像特征与机器人关系,在工作空间内把直线的始点与终点轨迹离散化,完成坐标转换,获取每个关节角度值,通过围绕焊接机器人各轴角度值确定欧拉角3个变量,利用欧拉角进行姿态规划,实现六轴焊接机器人关节运动姿态规划.实验结果表明,所提方法的六轴焊接机器人关节运动姿态规划精度较高,规划时间较短.     

空间机器人捕获运动目标的协调规划与控制方法

针对目标以任意轨迹运动且其轨迹可能与``有保证工作空间'不相交的问题, 提出了空间机器人捕获运动目标的协调规划与控制方法. 首先, 根据手眼视觉测量数据, 预测目标的运动路径, 由此确定空间机器人对目标的最优交会姿态及最佳捕获臂型; 其次, 规划基座姿态及机械臂关节角的轨迹; 最后, 采用协调控制的方法, 实现空间机器人系统对运动目标的最优捕获(以最优交会姿态及最佳捕获臂型对目标进行捕获). 仿真结果表明了该方法的有效性.     

一种用于人形机器人动作规划的ZMP补偿方法

人形机器人的动作规划是机器人研究领域的一个重要目标,ZMP（零力矩点）理论是人形机器人动作规划的一个基本理论。本文提出了以ZMP理论为基础的用于实现人形机器人动作规划的ZMP补偿方法,说明了该补偿方法的基本思想,推导了补偿数学模型,对该补偿方法进行了仿真实验,并用SHR-6S机器人进行了实体实验,对实验结果进行了实体分析,验证了该ZMP补偿方法在人形机器人动作规划中的有效性。     

自由落猫机器人时间最优下落轨迹研究

机器人在未知复杂环境下作业时,有从高处跌落的风险,所以需要考虑其空中的姿态调整能力,减轻由错误的着陆方式造成的伤害.当猫从高空坠落时,它总能通过自身调整安全落地.受这一生物学现象启发,通过研究猫能够安全落地的第一阶段,姿态调整阶段,首次提出以时间最优方式研究落猫机器人最优下落轨迹问题.首先利用轴对称双刚体模型导出机器人的数学模型,因为角速度不可积,将落猫机器人的姿态控制问题转变成非完整系统的运动规划问题.考虑到姿态调整所消耗的时间是决定调整结果较为重要的因素,随后以虚拟力矩输入取代真实角速度输入,建立时间优化函数,并构造了求解该函数的方法.然后以姿态调整耗时最短为控制目标,通过粒子群优化算法寻找目标最优解.最后运用所得最优解数据,在虚拟物理环境下进行了虚拟样机实验,并实现了落猫机器人的空中翻正动作.结果表明,该方法能有效地缩短自由下落机器人的姿态调整时间.     

仿人机器人两步步态规划算法研究

为了进一步提高仿人机器人步行时的稳定性,通过对人类步行的研究,并从两足步行机的两步步态规划方法中得到启发,对仿人机器人步行也进行类似的两步规划,但由于结构上的不同,仿人机器人中采用加入上肢运动补偿的方式实现平衡.规划仿人机器人的运动姿态,然后根据零力矩点必须落在稳定区域的原则,对仿人机器人的上肢运动轨迹进行求解,通过这种加入上肢补偿的两步规划来实现仿人机器人的稳定步行.从实验结果可以看出,采用这种两足步态规划方法,在仿人机器人两足步行时,可以使机器人上肢与下肢协调运动,从而提高了步行的稳定性.     

考虑跖趾关节运动的踏板式步行康复机器人运动规划

基于人正常步行时足部的运动特征,提出了一种利用机械约束即能实现步行时踝关节和跖趾关节运动姿态模拟的踏板式步行康复机器人,帮助老年人及偏瘫患者进行步行康复训练.通过分析步行时跖趾关节的背屈过程,对前踏板的运动姿态进行规划,并以此确定了约束导轨的轨迹.按照人正常平地步行过程对步行训练时双侧踏板的运动时序进行了规划,并根据步行时的时相分布关系规划了双侧曲柄的转速.利用MATLAB软件建立步行康复机器人的运动学仿真模型,验证了运动规划的可行性,说明该步行康复机器人可以模拟正常人步行时的步态及踝关节和跖趾关节的运动姿态,能够满足步行康复训练的要求.     

仿人足底肌电特征的机器人行走规划

模仿人类行走规律是规划双足机器人运动的基础.以往模仿人类步态主要通过视觉方法或惯性模块测量(Inertia measurement unit, IMU)方法捕捉人体特征点轨迹.这些方法不考虑零力矩点(Zero moment point, ZMP)的相似性.为解决该问题,本文提出了一种基于足底肌电信号(Electromyography, EMG)和惯性模块测量信号的混合运动规划方法.该方法通过测量足底肌电信号计算出足底压力中心的位置以及踝关节扭矩,结合惯性模块所测量的人体躯干和双足轨迹,来规划双足机器人的步态.首先,用肌电仪测量足底肌电信号,用惯性测量模块测量人体各肢体部分的姿态轨迹,经数据标定后作为仿人机器人的运动参考; 然后,通过预观控制输出稳定的步态.为确保仿人行走的效果,基于人体相似性对运动数据进行了步态优化.实验验证和分析表明, EMG信号超前ZMP约160ms,利用这个特性实现了对压力点位置的有效预测,提高了机器人在线模仿人类行走的稳定性.     

Effects of form and motion on judgments of social robots׳ animacy,likability, trustworthiness and unpleasantness

One of robot designers׳ main goals is to make robots as sociable as possible. Aside from improving robots׳ actual social functions, a great deal of effort is devoted to making them appear lifelike. This is often achieved by endowing the robot with an anthropomorphic body. However, psychological research on the perception of animacy suggests another crucial factor that might also contribute to attributions of animacy: movement characteristics. In the current study, we investigated how the combination of bodily appearance and movement characteristics of a robot can alter people׳s attributions of animacy, likability, trustworthiness, and unpleasantness. Participants played games of Tic-Tac-Toe against a robot which (1) either possessed a human form or did not, and (2) either exhibited smooth, lifelike movement or did not. Naturalistic motion was judged to be more animate than mechanical motion, but only when the robot resembled a human form. Naturalistic motion improved likeability regardless of the robot׳s appearance. Finally, a robot with a human form was rated as more disturbing when it moved naturalistically. Robot designers should be aware that movement characteristics play an important role in promoting robots׳ apparent animacy.     

Biological movement increases acceptance of humanoid robots as human partners in motor interaction

The automatic tendency to anthropomorphize our interaction partners and make use of experience acquired in earlier interaction scenarios leads to the suggestion that social interaction with humanoid robots is more pleasant and intuitive than that with industrial robots. An objective method applied to evaluate the quality of human–robot interaction is based on the phenomenon of motor interference (MI). It claims that a face-to-face observation of a different (incongruent) movement of another individual leads to a higher variance in one’s own movement trajectory. In social interaction, MI is a consequence of the tendency to imitate the movement of other individuals and goes along with mutual rapport, sense of togetherness, and sympathy. Although MI occurs while observing a human agent, it disappears in case of an industrial robot moving with piecewise constant velocity. Using a robot with human-like appearance, a recent study revealed that its movements led to MI, only if they were based on human prerecording (biological velocity), but not on constant (artificial) velocity profile. However, it remained unclear, which aspects of the human prerecorded movement triggered MI: biological velocity profile or variability in movement trajectory. To investigate this issue, we applied a quasi-biological minimum-jerk velocity profile (excluding variability in the movement trajectory as an influencing factor of MI) to motion of a humanoid robot, which was observed by subjects performing congruent or incongruent arm movements. The increase in variability in subjects’ movements occurred both for the observation of a human agent and for the robot performing incongruent movements, suggesting that an artificial human-like movement velocity profile is sufficient to facilitate the perception of humanoid robots as interaction partners.     

Control of bidirectional physical human–robot interaction based on the human intention

This paper presents a control strategy for human–robot interaction with physical contact, recognizing the human intention to control the movement of a non-holonomic mobile robot. The human intention is modeled by mechanical impedance, sensing the human-desired force intensity and the human-desired force direction to guide the robot through unstructured environments. Robot dynamics is included to improve the interaction performance. Stability analysis of the proposed control system is proved by using Lyapunov theory. Real experiments of the human–robot interaction show the performance of the proposed controllers.     

Asymmetric Velocity Moderation for human-safe robot control

With the increasing physical proximity of human–robot interaction, ensuring that robots do not harm surrounding humans has become crucial. Therefore, we propose asymmetric velocity moderation as a low-level controller for robotic systems to enforce human-safe motions. While our method prioritizes human safety, it also maintains the robot’s efficiency. Our proposed method restricts the robot’s speed according to (1) the displacement vector between human and robot, and (2) the robot’s velocity vector. That is to say, both the distance and the relative direction of movement are taken into account to restrict the robot’s motion. Through real-robot and simulation experiments using simplified HRI scenarios and dangerous situations, we demonstrate that our method is able to maintain the robot’s efficiency without undermining human safety.     

Time-space Viewpoint Planning for Guard Robot with Chance Constraint

This paper presents a novel movement planning algorithm for a guard robot in an indoor environment, imitating the job of human security. A movement planner is employed by the guard robot to continuously observe a certain person. This problem can be distinguished from the person following problem which continuously follows the object. Instead, the movement planner aims to reduce the movement and the energy while keeping the target person under its visibility. The proposed algorithm exploits the topological features of the environment to obtain a set of viewpoint candidates, and it is then optimized by a cost-based set covering problem. Both the robot and the target person are modeled using geodesic motion model which considers the environment shape. Subsequently, a particle model-based planner is employed, considering the chance constraints over the robot visibility, to choose an optimal action for the robot. Simulation results using 3D simulator and experiments on a real environment are provided to show the feasibility and effectiveness of our algorithm.

     

小型双足步行机器人的机构设计及其运动仿真

小型双足步行机器人具有多关节、多驱动器、多自由度的特点,本文以人体全身17个主要关节及其运动特性为研究对象,利用三维设计软件CATIA设计出小型双足步行机器人的全身机构,根据ZMP理论,以正常人行走的“X”形交叉动作为原则,规划出其各关节转角,在ADAMS下对其虚拟样机进行运动仿真,确保实现机器人的稳定步行和做舞蹈动作。     

Effects of movement speed and predictability in human–robot collaboration

Human–robot collaboration (HRC) is characterized by a spatiotemporal overlap between the workspaces of the human and the robot and has become a viable option in manufacturing and other industries. However, for companies considering employing HRC it remains unclear how best to configure such a setup, because empirical evidence on human factors requirements remains inconclusive. As robots execute movements at high levels of automation, they adapt their speed and movement path to situational demands. This study therefore experimentally investigated the effects of movement speed and path predictability of an industrial collaborating robot on the human operator. Participants completed tasks together with a robot in an industrial workplace simulated in virtual reality. A lower level of predictability was associated with a loss in task performance, while faster movements resulted in higher‐rated values for task load and anxiety, indicating demands on the operator exceeding the optimum. Implications for productivity and safety and possible advancements in HRC workplaces are discussed.     

Design of a quadruped robot for human–elephant conflict mitigation

Introduction

Human–elephant conflict is a major problem leading to crop damage, human death by elephants and elephants being killed by people. The surveillance and tracking of elephant herds are difficult due to their size and nature of movement.

Materials

In this article, we propose a four-wheeled quadruped robot to mitigate human–elephant conflict. The robot can detect movement of wild pachyderms in certain pockets along the forest borders through which the elephants enter into the human living areas from the forest. The robot is so designed that it can navigate with wheels on flat terrains and with legs on unfriendly rugged terrains with the help of mounted cameras.

Methods

The images of the wild elephant are captured and transmitted to the base stations and an SMS is sent to the forest officials indicating an elephant is found. We obtain a suitable kinematic model for both legs and wheels with control algorithm for the quadruped robot to move along a predetermined path.

Conclusion

The quadruped robot proposed is a solution to detect elephant movement without affecting the ecological conditions to overcome human–elephant conflict. The unpredictability of time and location of elephant arrival into the villages are considered the major issues that are resolved in this work. The results of our work contribute to elephant conservation issues and are suitable for the detection of elephants in forest border areas.