机器人操作手的最佳传力位姿的确定

本文在考察机器人操作手动态特性的基础上,研究了操作手的力传递特性,并根据向量系的广义相关性理论,定义了机器人操作手的力传递灵活性指标.最后,本文运用这些指标,解决了在给定操作力的条件下,所需驱动铰力最小的操作手的最佳位姿问题.     

农田信息采集机器人机构设计与奇异性分析

提出一种四轮并联机构的新型农田信息采集机器人．结构和越障原理分析结果表明,该机器人具有较 强的地形适应能力．为了研究机器人的奇异位形,根据雅可比矩阵的定义和D-H 矩阵法直接求出雅可比矩阵的解析 表达．根据机构的奇异性分类,利用动力学分析软件ADAMS 仿真得到了各奇异位形的精确位置和运动特点,与理 论分析相一致．根据以上分析设计的机器人物理样机能有效避免奇异位形．     

主被动混合式微创手术机械臂机构设计及灵巧度优化

研制出一款可开展微创手术的双机械臂机器人系统,该系统配合手术微器械可以实现精确的腹腔内手术操作.通过分析微创手术的手术环境及手术操作特点,提出了采用机器人开展微创手术对机器人自身机构设计的基本要求,并在此基础上重点对机械臂机构进行设计和优化.该机械臂可以按照微创手术的实际需求,实现机器人的术前摆位、术中器械操作及器械的快速拆装更换,并且可以从机构上保证术中器械在患者腹壁切口处位置不变,避免术中因手术器械运动而对腹壁切口造成非手术性损伤.此外,借助于机器人雅可比矩阵的奇异值,构造了基于条件数和可操作度的综合灵巧度评价指标函数,并采用序列二次规划算法对机械臂杆件参数进行优化.优化结果表明,机械臂具有良好的各向同性及可操作度,很好地满足了微创手术对机械臂机构灵活性的要求.     

三分支机器人协调操作及关节力矩优化

针对三分支机器人协调运动，采用分离影响系数法分离各个分支的雅可比矩阵和惯性矩阵，再重新组合成整个系统的雅可比矩阵和惯性矩阵，建立三分支机器人运动学和动力学方程．应用乘子罚函数方法，对三分支机器人基于最小关节驱动力矩优化设计,避免矩阵的奇异值分解，提高计算的稳定性，应用迭代方法，简化了问题的求解．     

冗余度机器人的可操作度和有限制条件下的最优轨迹规划

本文以冗余度机器人的逆运动学为基础，引入了扩展雅可比矩阵的概念；给出了便于讨论可操作度的几个重要定理；推导出了一般了发制条件下的癃 运动学最优解与最小范数解的关系。     

基于图像雅可比矩阵的智能机器人视觉跟踪

根据智能机器人视觉伺服的要求,建立了固定眼结构的MOTOMAN-SV3XL型工业机器人无标定视觉伺服系统.研究了目前在机器人视觉伺服研究领域中使用最为广泛的一类方法,即基于图像雅可比矩阵的方法.针对图像雅可比矩阵的特点,设计了一种基于简化Sage-Husa自适应滤波的图像雅可比矩阵在线估计算法,并将其应用于机器人视觉反馈控制任务中,实现了对二维平面上运动目标的跟踪,实验结果表明了该算法的有效性.     

基于无极卡尔曼滤波算法的雅可比矩阵估计

在基于图像的机器人视觉伺服中,采用在线估计图像雅可比的方法,不需事先知道系统的精确模型,可以避免复杂的系统标定过程。为了有效改善图像雅可比矩阵的在线估计精度,进而提高机器人的跟踪精度,针对机器人跟踪运动目标的应用背景,提出了利用无极卡尔曼滤波算法在线估计总雅可比矩阵。在二自由度的机器人视觉伺服仿真平台上,分别用卡尔曼滤波器（KF）、粒子滤波器（PF）和无极卡尔曼滤波器（UKF）三种算法进行总雅可比矩阵的在线估计。实验结果证明,使用UKF算法的跟踪精度优于其他两种算法,时间耗费仅次于KF算法。     

基于扩展雅可比矩阵的冗余液压驱动四足机器人运动控制

针对冗余液压驱动四足机器人运动学逆解问题,提出一种基于扩展雅可比矩阵的冗余液压驱动四足机器人运动控制方法.该方法既能解决冗余自由度带来的逆解多解问题,还能使机器人足端入地角度满足摩擦锥要求避免足端滑动.首先,规划机器人足端轨迹得到机器人足端速度,在分析机器人足端入地角度对机器人运动性能影响的基础上,结合机器人腿部结构几何关系,建立扩展雅可比矩阵,确立机器人关节角度速度和足端速度的映射关系,即得到机器人关节角度的解.然后,在对角步态下,通过仿真对传统的梯度投影法和提出的扩展雅可比矩阵法进行对比,理论分析及仿真表明传统的梯度投影法存在误差累积,且在实时性上不如扩展雅可比矩阵法.最后,实验验证了基于扩展雅可比矩阵逆运动学分析方法的可行性和有效性.     

PPRRRP和RRRPU肩关节康复外骨骼机构运动性能的分析比较

基于外骨骼机构的构型综合和优选原则,提出PPRRRP和RRRPU两种外骨骼构型.在优选的构型中,通过在人机连接处引入被动关节,使外骨骼机构和人体上臂形成的人机闭链转化为3-DOF（自由度）运动学恰约束系统,实现人机运动学相容.从人机闭链整体的角度,分别建立PPRRRP和RRRPU人机闭链运动学模型,通过对被动关节的合理分解及运动学特征分析,推导其运动学约束方程,并分别求得两闭链的速度雅可比矩阵,该方法降低了人机闭链运动学分析的复杂性.通过对速度雅可比矩阵的数值仿真,在冠状面、矢状面和水平面对2种外骨骼构型进行条件数倒数、可操作度椭球以及灵巧操作速度的分析比较.结果表明：在上述3个面内,PPRRRP构型的运动灵活度、运动各向同性和速度操作灵巧性的运动学性能要优于RRRPU.在此基础上,研制了PPRRRP构型的上肢康复外骨骼样机.     

冗余空间机器人最小姿态干扰运动控制

空间机器人（Space Robots,SR）机械手沿预定轨迹运动完成空间作业时会对卫星本体姿态产生干扰,影响正常通信和太阳能帆板定向,增加姿态控制燃料消耗。首先通过对SR非完整冗余（Nonholonomic Redundancy,NR）分析,求解不同作业任务SR逆运动学问题,提出对卫星本体不产生姿态干扰的固定姿态控制雅可比矩阵的灵活度准则;其次基于任务分层和NR控制方程,开发了最小姿态干扰运动控制算法;最后计算机仿真验证了算法的有效性。研究结果表明该算法可最小化机械手运动对卫星本体姿态干扰,可节省宝贵姿态控制燃料。     

Neural networks to determine task oriented dexterity indices for an underwater vehicle-manipulator system

A method for the fast approximation of dexterity indices for given underwater vehicle-manipulator systems (UVMS) configurations is presented. Common underwater tasks are associated with two well-known dexterity indices and two types of neural networks are designed and trained to approximate each one of them. The method avoids the lengthy calculation of the Jacobian, its determinant and the computationally expensive procedure of singular value decomposition required to compute the dexterity indices. It provides directly and in a considerably reduced computational time the selected dexterity index value for the given configuration of the system. The full kinematic model of the UVMS is considered and the NN training dataset is formulated by the conventional calculation of the selected dexterity indices. A comparison between the computational cost of the analytical calculation of the indices and their approximation by the two NN is presented for the validation of the proposed approach. This paper contributes mainly on broadening the applications of NN to a problem of high complexity and of high importance for UVMS high performance intervention.     

Kinematic analysis of a 3-PRS parallel manipulator

Although the current 3-PRS parallel manipulators have different methods on the arrangement of actuators, they may be considered as the same kind of mechanism since they can be treated with the same kinematic algorithm. A 3-PRS parallel manipulator with adjustable layout angle of actuators has been proposed in this paper. The key issues of how the kinematic characteristics in terms of workspace and dexterity vary with differences in the arrangement of actuators are investigated in detail. The mobility of the manipulator is analyzed by resorting to reciprocal screw theory. Then the inverse, forward, and velocity kinematics problems are solved, which can be applied to a 3-PRS parallel manipulator regardless of the arrangement of actuators. The reachable workspace features and dexterity characteristics including kinematic manipulability and global dexterity index are derived by the changing of layout angle of actuators. Simulation results illustrate that different tasks should be taken into consideration when the layout angles of actuators of a 3-PRS parallel manipulator are designed.     

The optimum design of robotic manipulators using dexterity indices

This paper presents new dexterity indices that can be applied to planar and spatial manipulators. These indices are based on the condition number of the Jacobian matrix of the manipulators which is known to be a measure of their kinematic accuracy. Dexterity indices based on that same criterion have been presented elsewhere. However, due to the formulation of the kinematic equations, the existing indices are affected by a scaling of the manipulator when both the position and the orientation of the end effector are included in the kinematic equations. A new formulation of these equations is proposed here to avoid this problem of dimensional dependence. Two dexterity indices are presented for planar manipulators: the first one is based on a redundant formulation of the velocity equations whereas the second one is based on the mininum number of parameters. The corresponding indices are also derived for spatial manipulators. Finally, an example is included to illustrate the use of these indices in the context of design and optimization of manipulators.     

手指机构的速度操作灵巧性分析

在简要介绍开端钢缆传动结构及其特征矩阵的基础上，将操作臂速度可操作性椭 球的概念引入钢缆传动手指机构，给出了手指具有各向同性速度传递性质的条件．建立了开 端钢缆传动中各缆速间的协调关系，并根据缆速空间与指端速度空间之间的映射关系，给出 了建立手指指端操作速度矢量集合的方法．为评价指端实际的速度操作灵巧性，还提出新的 度量指标，并结合算例介绍了对手指机构进行操作灵巧性分析的方法．     

A fuzzy approximation to dexterity measures of mobile manipulators

In this paper, a fuzzy system is trained to approximate the manipulability index and the inverted condition number of a mobile manipulator. The kinematic model of a mobile platform with the attached manipulator is fused using twist theory and certain dexterity measures are examined throughout the configuration space. A Takagi–Sugeno–Kang fuzzy system is designed to approximate the dexterity measures and it is evaluated both for its error and its efficiency in computational cost. The proposed methodology is proved as a very efficient approximation that can be utilized in real-time motion planning algorithms without significantly adding computational cost to the controller.     

手指机构力操作灵巧性的分析与评价

本文对开端钢缆传动手指机构的力操作灵巧性问题进 行研究．首先,定义了钢缆张力椭球．在此基础上,分析了手指机构力操作的位形灵巧性及 钢缆传动结构对位形灵巧性的影响．其次,根据钢缆张力空间与指端操作力空间之间的映射 关系,给出了建立指端在给定操作位形处的操作力矢量集合的几何方法．得到的矢量集合反 映了考虑钢缆张力限制时,指端实际的力操作能力．为评价指端实际的力操作灵巧性,还提 出两个新的度量指标．最后,给出了手指机构力操作灵巧性分析的示例．     

Kinematic Analysis of a Macro–Micro Redundantly Actuated Parallel Manipulator

In this paper the kinematic and Jacobian analysis of a macro–micro parallel manipulator is studied in detail. The manipulator architecture is a simplified planar version adopted from the structure of the Large Adaptive Reflector (LAR), the Canadian design of the next generation of giant radio telescopes. This structure is composed of two parallel and redundantly actuated manipulators at the macro and micro level, which both are cable-driven. Inverse and forward kinematic analysis of this structure is presented in this paper. Furthermore, the Jacobian matrices of the manipulator at the macro and micro level are derived, and a thorough singularity and sensitivity analysis of the system is presented. The kinematic and Jacobian analysis of the macro–micro structure is extremely important to optimally design the geometry and characteristics of the LAR structure. The optimal location of the base and moving platform attachment points in both macro and micro manipulators, singularity avoidance of the system in nominal and extreme maneuvers, and geometries that result in high dexterity measures in the design are among the few characteristics that can be further investigated from the results reported in this paper. Furthermore, the availability of the extra degrees of freedom in a macro–micro structure can result in higher dexterity provided that this redundancy is properly utilized. In this paper, this redundancy is used to generate an optimal trajectory for the macro–micro manipulator, in which the Jacobian matrices derived in this analysis are used in a quadratic programming approach to minimize performance indices like minimal micro manipulator motion or singularity avoidance criterion.     

Dimensional synthesis of a robotized cell of support fixture

In this paper, an optimal designed 8-SPU parallel mechanism, acting as a cell of the self-configurable fixture which is used to support and clamp the thin-walled, large-scale plate and shell workpiece in automotive, aircraft and ship manufacturing industries, is proposed. In order to locate the maximum workspace with the global dexterity and conformity dexterity, single and multiple objective optimizations are performed under conditions of geometric constraints and kinematic performance indices by particle swarm optimization. The structural comprehensive parameters of parallel mechanism, such as the layout of joint points on the upper platform, the angle between two limbs of leg, and the ratio of radii of fixed to moving platforms, are optimized to obtain the optimal design dimensions. Furthermore, the effect of the optimized variables on kinematic performance indices is also intensively investigated. The compared results of the two optimization approaches indicate the feasibility of the proposed procedures.     

A 6-DOF adaptive parallel manipulator with large tilting capacity

In this paper, a novel 6 degrees of freedom (DOFs) adaptive parallel manipulator with large tilting capacity is presented. The manipulator consists of four identical peripheral limbs and one center limb connecting the base and the moving platform. Due to the special architecture, the doubly actuated center limb of the manipulator could have infinite inverse solutions. In every configuration of the end-effector, the manipulator can adapt its center limb to the position and orientation with best dexterity. An optimization equation for obtaining the optimized dexterity of the manipulator is introduced to solve this nonholonomic problem, which also makes the manipulator capable of large tilting capacity. Targeting for the application of five-face machining, the detailed kinematic analysis of the manipulator is developed, which includes the closed-form solutions of inverse position problems, the singularity, dexterity, workspace and tilting capability. The analysis developed in this paper shows that the proposed manipulator has large tilting capacity and thus a suitable candidate for five-face machining.     

机器人运动分析的一组新等式推证及应用

本文推证了一组刚体旋转矩阵与角速度矢的新等式，以该组等式为基础，文中提出并讨论了一种利用旋转矩阵的导数矩阵分析机器人运动的方法，所提方法在文中的运用表明，它可以取代以往过于繁琐的图解法和递推法，成为一种简明有效的机器人运动分析方法，作为该法应用结果，文中给出了由ｎ个杆件构成的ｎ个自由度机器人雅可比矩阵的一种简明封闭式，具有一定实和价值，这里的方法可作为一般刚体运动分析理论的补充。