机器人灵活手的运动分析和力分析

机器人灵活手可以稳定地抓持任意形状物体,或利用手指的运动操纵物体相对于机器人末杆(或手掌)的运动.它的运动学和力传递关系比一般开链机器人复杂得多.本文分析了在被抓持物体与手指指尖,手指指尖与手指关节之间力和虚位移的关系.利用线性变换的理论揭示了过约束、欠约束和奇异状态的形成条件.本文还分析了手指机构冗余自由度、亏缺自由度和奇异位形对抓持的影响.这些结果为机器人灵活手的设计和控制方案的规划提供了理论依据.     

虚拟手的姿态控制与变形仿真

iHandRehab应用机器人技术与虚拟现实技术对手部损伤患者进行康复训练。主动模式下的训练任务需要在虚拟环境中模拟人手抓持和释放物体的真实过程,难点集中在虚拟手与刚性物体接触时的姿态控制和局部变形计算。根据人手的组织结构和运动特征将食指和拇指简化为3指节串联机构,通过改变各关节的旋转角度来实现虚拟手的自由运动。虚拟抓持过程中以手指的运动学模型为基础,结合前后指节需要满足的约束关系确定虚拟手的最终姿态。指节和物体分别采用点壳和距离场模型进行碰撞检测,根据点壳上碰撞点的嵌入信息计算虚拟手在接触区域的局部变形量。实验结果表明:模型能够实时准确地模拟人手抓持刚性物体时的真实状态。     

一种新的自组装模块化群体机器人——对接机构设计与自组装控制

基于新型自组装模块化群体机器人Sambot,研究并实现了多个机器人之间的自主对接与自组装控制．首先, 提出了一种由对接卡扣与对接卡槽组成的新型对接机构,它可以使多个Sambot在一定对接偏差范围内,从前、后、 左、右4个方向同时进行对接;其次,采用基于行为的控制方法,仅依赖机器人自身红外传感器的局部感知和通信能力, 实现了对接机器人寻找目标、导航和自主对接等自组装行为;最后,成功完成了两个Sambot的自主对接与自组装控制实验． 实验结果表明,本文提出的自组装控制方法可以直接扩展到多个Sambot的情形,来构建任意构型的集合体机器人．     

仿人机器人轻型高刚性手臂设计及运动学分析

重点研究了7自由度轻型高刚性作业型仿人机器人手臂的机构设计和运动学分析方法.首先使用动力学仿真、有限元分析与实验测试相结合的方法,设计了仿人机器人手臂,该机械臂结构紧凑、质量轻、刚度高.同时,提出结合查询数据库和逆运动学计算去模仿人类手臂姿态,从而获得逆运动学最优解的方法.该方法不仅解决了冗余自由度带来的逆运动学多解问...     

一类Power抓持接触力分解的一般表达式

与灵巧抓持相比,Power抓持可承受较大的外部载荷 ,能够更稳定地抓持物体．但由于抓持机构与物体间的约束较多,且接触点可出现在抓持机 构中活动度有限的构件上,因此不能采用已有的适用于灵巧抓持的接触力分解方法对其接触 力进行分解．本文在对一类Power抓持机构的结构特征进行分析的基础上,适当地建立了接 触坐标系和物体坐标系．通过对接触力空间进行分解,给出了抓持接触力分解的一般表达式 ．并根据该表达式,建立了此类Power抓持的外部载荷与关节力矩及接触力之间的显函数关 系．     

基于万向式关节的模块化自重构机器人

提出了一种基于万向式关节的模块化自重构机器人——UBot．该机器人模块结构紧凑、刚性好、运动灵活,具有运动、 重构和处理任务的能力．它由许多标准模块组成,模块均采用万向式结构的正立方体外形,具有4个可以与相邻模块连接\/断开的连接面． 设计了钩爪式连接机构,它可以快速可靠地与相邻模块连接/断开,该连接机构连接后具有自锁功能,节省能量．设计了 模块电气系统．最后进行了连接机构和机器人运动实验,证明了UBot系统的可靠性和运动灵活性．     

一种并联激光焊接机器人的机构设计与运动学分析

提出了一种3 分支5 自由度的并联激光焊接机器人,通过3 个分支共同作用,使整机具备了5 个自由 度的空间加工能力．针对激光焊接,通过分析该机器人的结构特性,建立了其正反解运动学模型,通过解析法求解 该模型并进行了计算仿真．最后,对机器人进行激光拼焊实验,仿真数据和实验结果表明,本文研究的并联机器人 机构适用于实际的高速、高精度激光焊接．     

基于多传感器信息的冗余度机器人运动规划与控制

提出了一种基于多传感器信息的冗余度机器人规划与控制的模型,利用不同传感器本身的特性，分阶段地对多传感器的信息进行融合，减少规划时间, 并在冗余度机器人的运动过程中，不断地提高位姿检测的精度．将远距离的宏观规划和近距离的微调结合起来，增加了抓持的可靠性．利用移动冗余度操作臂系统结构的几何特点进行了运动学分析、避奇异的方法研究及仿真对比分析．应用所提出的研究方法获得了较好的实验效果．     

刚性关节链模型在保弧长曲线变形中的应用

采用刚性关节链模型解决了保弧长的曲线变形问题．基于逆向运动学,进一步解决了中间关节点目标约束的问题,避免了单纯的逆向运动学重构关节链的繁复工作．定义一个关节角限制意义上的势函数作为目标函数,用求解约束优化问题的方法把动力学引入到逆向运动学方法中,体现了变形物体的物理属性,因而可以实现较逼真的动画效果．该方法适用于计算机角色动画、布料仿真、机器人任务规划等应用领域。     

新型变几何桁架机器人的简化刚体运动分析

本文对一种新型变几何桁架机器人机构，利用机构简化模型在位置分析的基础上进行了刚体运动学分析，求出了机器人系统各构件运动参数的显式解析解，为这种机器人的刚性动力学和弹性动力学分析打下了基础。     

An algorithm for cooperative task allocation in scalable,constrained multiple robot systems

The current trends in the robotics field have led to the development of large-scale multiple robot systems, and they are deployed for complex missions. The robots in the system can communicate and interact with each other for resource sharing and task processing. Many of such systems fail despite the availability of necessary resources. The major reason for this is their poor coordination mechanism. Task planning, which involves task decomposition and task allocation, is paramount in the design of coordination and cooperation strategies of multiple robot systems. Task allocation mechanism allocates the task in a mission to the robots by maximizing the overall expected performance, and thereby reducing the total allocation cost for the team. In this paper, we formulate a heuristic search-based task allocation algorithm for the task processing in heterogeneous multiple robot system, by maximizing the efficiency in terms of both communication and processing cost. We assume a set of decomposed tasks of a mission, which needs to be allocated to the robots. The near-optimal allocation schemes are found using the proposed peer structure algorithm for the given problem, where the number of the tasks is more than the robots present in the system. The cost function is the summation of static overhead cost of robots, assignment cost, and the communication cost between the dependent tasks, if they are assigned to different robots. Experiments are performed to verify the effectiveness of the algorithm by comparing it with the existing methods in terms of computational time and quality of solution. The experimental results show that the proposed algorithm performs the best under different problem scales. This proves that the algorithm can be scaled for larger system and it can work for dynamic multiple robot system.     

Development of multiple robotic fish cooperation platform

This article presents the development of a multiple robotic fish cooperation platform, which is established by employing a group of radio-controlled, multi-link fish-like robots. This work is inspired by the observation from nature that the capability of one single fish is limited, as in order to survive the atrocious circumstances in the sea, fish often swim in schools. The analogical situations occur in the robotic fish case. In engineering applications, most missions are so complex that they must be accomplished by effective cooperation of multiple fish robots. The platform presented in this article, as a novel test bed for multiple robotic fish cooperation, can be applied to different types of complex tasks. More importantly, it provides a good platform to test and verify all kinds of algorithms and strategies for cooperation of multiple underwater mobile robots. We use two cooperative tasks as examples to heuristically demonstrate the performance of this platform.     

Distributed Service-Based Cooperation in Aerial/Ground Robot Teams Applied to Fire Detection and Extinguishing Missions

This paper presents a system for the coordination of aerial and ground robots for applications such as surveillance and intervention in emergency management. The overall system architecture is described. An important part for the coordination between robots is the task allocation strategy. A distributed market-based algorithm, called S + T, has been developed to solve the multi-robot task allocation problem in applications that require cooperation among the robots to accomplish all the tasks. Using this algorithm, robots can provide transport and communication relay services dynamically to other robots during the missions. Moreover, the paper presents a demonstration with a team of heterogeneous robots (aerial and ground) cooperating in a mission of fire detection and extinguishing.     

Fuzzy logic decision making for multi-robot security systems

The paper proposes a fuzzy logic decision making system for security robots that deals with multiple tasks with dynamically changing scene. The tasks consist of patrolling the environment, inspecting for missing items, chasing and disabling intruders, and guarding the area. The decision making considers robot limitations such as maximum floor coverage per robot and remaining robot battery energy, as well as cooperation among robots to complete the mission. Each robot agent makes its own decision based on its internal information as well as information broadcast to it by other robots about events such as intruder sighting. As a result the multi-robot security system is distributive without a central coordinator. The system has been implemented both in simulations and on actual robots and its performance has been verified under different scenarios.     

路网约束下异构机器人系统路径规划方法

由无人机(Unmanned aerial vehicles, UAV)和地面移动机器人组成的异构机器人系统在协作执行任务时,可以充分发挥两类机器人各自的优势.无人机运动灵活,但通常续航能力有限;地面机器人载荷多,适合作为无人机的着陆平台和移动补给站,但运动受路网约束.本文研究这类异构机器人系统协作路径规划问题.为了降低完成任务的时间代价,提出一种由蚁群算法(Ant colony optimization, ACO)和遗传算法(Genetic algorithm, GA)相结合的两步法对地面机器人和无人机的路线进行解耦,同时规划地面机器人和无人机的路线.第1步使用蚁群算法为地面机器人搜索可行路线.第2步对无人机的最优路径建模,采用遗传算法求解并将无人机路径长度返回至第1步中,用于更新路网的信息素参数,从而实现异构协作系统路径的整体优化.另外,为了进一步降低无人机的飞行时间代价,研究了无人机在其续航能力内连续完成多任务的协作路径规划问题.最后,通过大量仿真实验验证了所提方法的有效性.     

Dynamic coordination between robots: self-organized timing selection in a juggling-like ball-passing task.

This paper describes the hierarchical architecture for a rhythmic coordination between robots, which suits juggling-like tasks involving sensory-motor coordination. The authors' approach, which is interpreted as a "bidirectional weak coupling" to the environment, does not require either the environmental model or continuously monitoring the environment but can adapt the robots to a change in the environment, owing to the interaction between the robots and the environment at the ball contact. The proposed architecture contains two passive-control mechanisms, the "open-loop stable mechanism" and the "entrainment mechanism," that lead to the emergence of self-organized temporal structure for rhythmic movement. This dynamic pattern in the whole system realizes the stable coordinated motion between robots. The authors demonstrate two motion patterns between two robots passing two balls, and confirm the effectiveness of the approach.     

模块化可重构机器人动力学研究进展

模块化可重构机器人由于其构型多变,运动形式丰富等特点,可以在非结构化环境或未知环境中执行任务,在最近几年迅速成为机器人研究领域的前沿和热点. 模块化可重构机器人在军事、医疗、教育等众多工程领域具有广泛的应用前景,其典型代表包括仿生多足模块化机器人、模块化可重构机械臂、晶格式模块化机器人等. 模块化可重构机器人丰富的构型设计、多样的连接特征、不断拓展的应用范围,给动力学建模与控制带来了很多挑战和机遇. 本文首先阐述了模块化可重构机器人的研究背景和意义,并概述了其构型分类与设计、构型描述与运动学建模方法.随后,本文系统回顾了模块化可重构机器人动力学研究中相关问题的最新进展,包括：(1)系统整体动力学建模;(2)结合面以及对接机构动力学建模;(3)基于动力学模型的控制方法. 本文最后提出了模块化可重构机器人动力学研究中若干值得关注的问题.     

A Paradigm for Dynamic Coordination of Multiple Robots

In this paper, we present a paradigm for coordinating multiple robots in the execution of cooperative tasks. The basic idea in the paper is to assign to each robot in the team, a role that determines its actions during the cooperation. The robots dynamically assume and exchange roles in a synchronized manner in order to perform the task successfully, adapting to unexpected events in the environment. We model this mechanism using a hybrid systems framework and apply it in different cooperative tasks: cooperative manipulation and cooperative search and transportation. Simulations and real experiments demonstrating the effectiveness of the proposed paradigm are presented.     

CONRO: Towards Deployable Robots with Inter-Robots Metamorphic Capabilities

Metamorphic robots are modular robots that can reconfigure their shape. Such capability is desirable in tasks such as earthquake search and rescue and battlefield surveillance and scouting, where robots must go through unexpected situations and obstacles and perform tasks that are difficult for fixed-shape robots. The capabilities of the robots are determined by the design specification of their modules. In this paper, we present the design specification of a CONRO module, a small, self-sufficient and relatively homogeneous module that can be connected to other modules to form complex robots. These robots have not only the capability of changing their shape (intra-robot metamorphing) but also can split into smaller robots or merge with other robots to create a single larger robot (inter-robot metamorphing), i.e., CONRO robots can alter their shape and their size. Thus, heterogeneous robot teams can be built with homogeneous components. Furthermore, the CONRO robots can separate the reconfiguration stage from the locomotion stage, allowing the selection of configuration-dependent gaits. The locomotion and automatic inter-module docking capabilities of such robots were tested using tethered prototypes that can be reconfigured manually. We conclude the paper discussing the future work needed to fully realize the construction of these robots.     

Towards cooperation of heterogeneous,autonomous robots: A case study of humanoid and wheeled robots

In this paper a case study of the cooperation of a strongly heterogeneous autonomous robot team, composed of a highly articulated humanoid robot and a wheeled robot with largely complementing and some redundant abilities is presented. By combining strongly heterogeneous robots the diversity of achievable tasks increases as the variety of sensing and motion abilities of the robot system is extended, compared to a usually considered team of homogeneous robots. A number of methodologies and technologies required in order to achieve the long-term goal of cooperation of heterogeneous autonomous robots are discussed, including modeling tasks and robot abilities, task assignment and redistribution, robot behavior modeling and programming, robot middleware and robot simulation. Example solutions and their application to the cooperation of autonomous wheeled and humanoid robots are presented in this case study. The scenario describes a tightly coupled cooperative task, where the humanoid robot and the wheeled robot track a moving ball, which is to be approached and kicked by the humanoid robot into a goal. The task can be fulfilled successfully by combining the abilities of both robots.