基于空间模型技术的新型正交5-DOF并联机床的运动学传递性能分析

提出了一种新型正交5-DOF并联机床,研究了这种新型机床的运动传递性能.推导出这种机床的运动传递平衡方程,定义了运动传递性能评价指标、速度各向同性性能评价指标及各全域性能评价指标,应用空间模型技术,绘制了各全域性能图谱,为这种新型正交5-DOF并联机床的参数优化奠定理论基础.这种新型正交5-DOF并联机床具有结构简单、承载能力强、初始装配位姿解耦、工艺性好等优点,适用于空间曲面(磨具、叶片等)零件的加工及气囊抛光等领域.

一种新型正交5-DOF并联气囊抛光机床的运动传递性能分析

提出了一种新型正交5-DOF并联气囊抛光机床,研究了这种新型5-DOF并联气囊抛光机床的运动学传递性能,定义了速度传递性能评价指标和各向同性性能评价指标,基于这种并联机器人的结构布局特点,分析了各性能评价指标在工作空间内的分布规律,为这种并联气囊抛光机床的应用提供了理论基础。这种新型正交5-DOF并联气囊抛光机床具有结构简单、承载能力强、运动惯性小、初始装配位姿解耦、工艺性好等优点,可用于空间曲面(磨具、叶片等)零件的加工及精密抛光等领域。

Parameters Optimization of a Novel 5-DOF Gasbag Polishing Machine Tool

The research on the parameters optimization for gasbag polishing machine tools, mainly aims at a better kinematics performance and a design scheme. Serial structural arm is mostly employed in gasbag polishing machine tools at present, but it is disadvantaged by its complexity, big inertia, and so on. In the multi-objective parameters optimization, it is very difficult to select good parameters to achieve excellent performance of the mechanism. In this paper, a statistics parameters optimization method based on index atlases is presented for a novel 5-DOF gasbag polishing machine tool. In the position analyses, the structure and workspace for a novel 5-DOF gasbag polishing machine tool is developed, where the gasbag polishing machine tool is advantaged by its simple structure, lower inertia and bigger workspace. In the kinematics analyses, several kinematics performance evaluation indices of the machine tool are proposed and discussed, and the global kinematics performance evaluation atlases are given. In the parameters optimization process, considering the assembly technique, a design scheme of the 5-DOF gasbag polishing machine tool is given to own better kinematics performance based on the proposed statistics parameters optimization method, and the global linear isotropic performance index is 0.5, the global rotational isotropic performance index is 0.5, the global linear velocity transmission performance index is 1.012 3 m/s in the case of unit input matrix, the global rotational velocity transmission performance index is 0.102 7 rad/s in the case of unit input matrix, and the workspace volume is 1. The proposed research provides the basis for applications of the novel 5-DOF gasbag polishing machine tool, which can be applied to the modern industrial fields requiring machines with lower inertia, better kinematics transmission performance and better technological efficiency.

An Analysis of the Inverse Kinematics for a 5-DOF Manipulator

This paper proposes an analytical solution for a 5-DOF manipulator to follow a given trajectory while keeping the orientation of one axis in the end-effector frame. The forward kinematics and inverse kinematics for a 5-DOF manipulator are analyzed systematically. The singular problem is discussed after the forward kinematics is provided. For any given reachable position and orientation of the end-effector, the derived inverse kinematics will provide an accurate solution. In other words, there exists no singular problem for the 5-DOF manipulator, which has wide application areas such as welding, spraying, and painting. Experiment results verify the effectiveness of the methods developed in this paper. Keywords Inverse kinematics - modeling and control - 5-DOF manipulator This work was supported by the National High Technology Research and Development Program of China (No. 2002AA422160), and the National Key Fundamental Research and Development Project of China (973, No.2002CB312200)De Xu graduated from Shandong University of Technology (SUT), China in 1985. He received a Masters degree from SUT in 1990, and a Ph.D. degree from Zhejiang University, China in 2001. He has been with the Institute of Automation, at the Chinese Academy of Sciences (CASIA) since 2001. He is an associate professor with the Laboratory of Complex Systems and Intelligence Science, CASIA. He worked as on academic visitor in the Department of Computer Science, at the University of Essex from May to August 2004. He is a member of the IEEE. His research interests include robotics and automation, especially the control of robots such as visual and intelligent control.Carlos Antonio Acosta Calderon received a B.S. degree in Computer Science Engineering from Pachuca Institute of Technology, Mexico in 2000, and a M.Sc. degree in Computer Science (Robotics and Intelligent Machines) from the University of Essex, UK in 2001. He is currently pursuing a Ph.D degree in Computer Science at the University of Essex, UK. His research interests have focused on mobile robots, in particular, the coordination of multi-robot systems, mobile manipulators, and learning by imitation. He is a member of IEEE.John Q. Gan received a B.Sc. degree in electronic engineering from Northwestern Polytechnic University, China in 1982, a M.Eng. degree in automatic control and a Ph.D degree in biomedical electronics from Southeast University, China in 1985 and 1991, respectively. He is a Senior Lecturer in the Department of Computer Science at the University of Essex, UK. He has co-authored a book, and published over 100 research papers. His research interests are in robotics and intelligent systems, brain-computer interfaces, pattern recognition, signal processing, data fusion, and neurofuzzy computation.Huosheng Hu is a Professor in the Department of Computer Science, at the University of Essex, and head of the Human Centered Robotics Group. His research interests include autonomous mobile robots, human-robot interaction, evolutionary robotics, multi-robot collaboration, embedded systems, pervasive computing, sensor integration, RoboCup, intelligent control, and networked robotics. He has published over 200 papers in journals, books, and conferences, and received two best paper awards. He is a founding member of the IEEE Society of Robotics and Automation Technical Committee of Internet and Online Robots, and a member of the IASTED Technical Committee on “Robotics” for 2001–2004. He was a Conference Chairman for the 1st European Embedded Systems Conference in Paris, 1996, and has been a member of the Program Committees for many international conferences such as IROS (2005–2006), IASTED Robotics and Applications Conferences (2000-present), and RoboCup Symposiums (2000–2004). Dr. Hu is a Chartered Engineer, a senior member of IEEE, and a member of IEE, AAAI, ACM, IASTED and IAS.Min Tan graduated from Tsing Hua University, China in 1986. He received a Ph.D. degree in 1990 from CASIA. He is a professor with the Laboratory of Complex Systems and Intelligence Science, CASIA. He has published over 100 papers in journals, books, and conferences. His research interests include robotics and complex system theory.

Forward Position Analysis of 5-DOF Parallel Mechanism

A systematic method for the forward kinematics of a five degrees of freedom （5-DOF） parallel mechanism with the legs＇ topology 4-UPS/UPU, is developed. Such mechanism is composed of a movable platform connected to the base by four identical 6-DOF active limbs plus one active limb with its DOF being exactly the same as the specified DQF of the movable platform. Three translational and two rotational DOFs can be achieved. Firstly, a set of polynomial equations of forward position analysis is formulated based on the architecture of the mechanism. Then the system of equations is degraded from five-dimensional to three-dimensional by means of analytic elimination. Method of least squares and Gauss-Newton algorithm are used to construct the objective function and to solve it, respectively. Example shows that through 4-time iteration within 16 ms the ohjective, function converaes to the provided error tolerance. 10^-4.

基于单开链和方位特征集的5-DOF串并联构型综合

根据单开链和方位特征集设计了一种5自由度串并联机器人,并对5自由度串并联机器人并联机器人的运动学,对并联机构的位置逆解和动平台速度进行分析。运用Adams软件对设计的5自由度串并联机器人进行仿真分析,并验证机构的可行性。结果表明,该机构具有运动比较平稳、工作空间大等特点,对5自由度串并联机构多驱动器控制提供了参考依据。

Architecture Singularity Analysis of 4-U■S/U■U 5-DOF Parallel Mechanism

Architecture singularity of a parallel mechanism with five degrees of freedom (DOF) is analyzed. Such mechanism consists of a movable platform connected to the base by five active limbs. Four of them are identical 6-DOF limbs and the last one has the same DOF as the specified DOF of the movable platform. Based on the kinematics analysis, two categories of architecture singularities for such mechanism are proposed. Then the sufficient condition for each singularity is researched. Results show that the mechanism is singular when it employs each category of the proposed architecture, provided that it satisfies the corresponding sufficient condition. It can be concluded that the proposed two categories of architecture singularities should be avoided with the following dimensional synthesis of such mechanism.

5-DOF并串联机器人运动学分析及仿真

并联机器人强度刚度较高,但是工作空间较小;串联机器人工作空间较大,但强度刚度较小。混联机构因兼顾了并联和串联机构的优点而具有更加广泛的应用前景。文中介绍了一种新型五自由度并串联机器人来实现复杂曲面的加工。应用螺旋理论对其运动性质进行分析并计算了自由度。通过数值法推导了机器人的正解,运用解析法推导了机器人的反解。用SolidWorks构建了机器人的三维模型并导入到ADAMS中对其进行运动学仿真。仿真结果显示,该机器人能够实现复杂曲面的加工,可以为工业生产提供帮助。

5-DOF机械手运动学与轨迹规划分析

针对所设计的5-DOF机械手,使用D-H参数法建立正运动学模型,并利用反变换法结合几何法得到了逆运动学的封闭解表达式。通过求解目标轨迹上路径点的逆解,利用MATLAB软件进行了逆运动学仿真,分别对两组逆解进行轨迹规划,得到相同的末端轨迹,验证了关节角逆运动学方程关系及其正确性。在此基础上,对符合关节转角范围的一组逆解进行多项式拟合,并采取分段拟合的方法,降低多项式次数并减小了误差,得到关节变量关于时间t的显示解析式,拟合结果精确,便于实现对输入舵机的实时控制。最后,利用机构测量仿真,证明了拟合解析式的准确性。

Dimensional synthesis of a novel 5-DOF reconfigurable hybrid perfusion manipulator for large-scale spherical honeycomb perfusion

A novel hybrid perfusion manipulator(HPM)with five degrees of freedom(DOFs)is introduced by combining the 5PUS-PRPU(P,R,U and S represent prismatic,revolute,universal and spherical joint,respectively)parallel mechanism with the 5PRR reconfigurable base to enhance the perfusion efficiency of the large-scale spherical honeycomb thermal protection layer.This study mainly presents the dimensional synthesis of the proposed HPM.First,the inverse kinematics,including the analytic expression of the rotation angles of the U joint in the PUS limb,is obtained,and mobility analysis is conducted based on screw theory.The Jacobian matrix of 5PUS-PRPU is also determined with screw theory and used for the establishment of the objective function.Second,a global and comprehensive objective function(GCOF)is proposed to represent the Jacobian matrix’s condition number.With the genetic algorithm,dimensional synthesis is conducted by minimizing GCOF subject to the given variable constraints.The values of the designed variables corresponding to different configurations of the reconfigurable base are then obtained.Lastly,the optimal structure parameters of the proposed 5-DOF HPM are determined.Results show that the HPM with the optimized parameters has an enlarged orientation workspace,and the maximum angle of the reconfigurable base is decreased,which is conducive to improving the overall stiffness of HPM.

5-UPS/PRPU 5自由度并联机床运动学分析

介绍了一种新型的5-UPS/PRPU5自由度并联机床,定平台通过五个结构完全相同的驱动分支UPS分支以一个约束分支PRPU分支与动平台相连接。该机床可以实现三维移动和两维转动,PRPU分支关节变量反映了动平台位姿,为实现闭环控制提供了条件。通过对其运动学进行分析和计算,确定了中间分支对动平台的约束运动,建立了该机床的运动学反解方程和雅可比矩阵,并通过机床样机试验验证了理论分析的正确性。

4-UPS-RPS空间5自由度并联机构运动学分析

提出了能实现三维转动和二维移动的4-UPS-RPS空间5自由度并联机构,并对该机构进行了运动学分析。4-UPS-RPS并联机构包含5条分支,其中4条分支为U-P-S(虎克铰-移动副-球副)型结构,1条分支为R-P-S(转动副-移动副-球铰)型结构。建立了该机构的位置反解数学模型,推导出了该机构的速度雅可比矩阵和加速度分析表达式,求解了该机构的位置反解、速度和加速度,并采用ADAMS软件对机构的运动学进行模拟仿真,仿真结果表明理论分析结果完全正确,为该并联机构的实际应用奠定了理论依据。

5-UPS/PRPU并联机床工作空间分析

介绍了新型5-UPS/PRPU五自由度并联机床的运动学反解,分析了其工作空间。以刀尖点为参考点对机床进行了运动学反解分析和工作空间的搜索。定义了灵活刀具倾斜角,使得只用一个参数就能够实现对工作空间的降维描述。对机床工作空间进行了以刀尖点为参考点的三维描述,并对影响机床工作空间大小的几何约束条件进行了分析。根据机床的实际结构参数对工作空间进行了算例分析,并以三维图形形式直观方便地描述了机床的工作空间。机床的最大可达工作空间为800×300的圆柱体,灵活工作空间为400×300的圆柱体,最大灵活刀具角为25°,分析结果与机床的实际运行情况基本一致。

5-UPS/PRPU五自由度并联机床动力学建模

介绍了一种新型的 5 UPS/PRPU五自由度并联机床 ,为该机床建立了基于动平台位姿参数的动力学模型。分析了机床中主要构件的运动情况 ,建立了各个构件的运动速度与机床驱动速度的映射关系 ,推导了各个构件的惯性力、重力、切削力等外力所产生的等效驱动力 ,建立了机床驱动力与运动参数之间关系的动力学解析方程。

5-UPS/PRPU五自由度并联机床的性能分析

针对一种新型五自由度并联机床机构利用雅克比矩阵的条件数作为衡量机构灵巧度的指标,考虑到线速度与角速度和力与力矩的不同量纲,分别给出了不同的灵巧度指标,分析了它们在工作空间内的分布情况,为该机床的设计和实用化奠定了理论基础。

5自由度并联机器人设计方法

本论文以螺旋理论为基础 ,提出一种系统的结构综合方法 .根据各条支链对运动平台所提供的反螺旋约束的线性关系 ,研究了构成五自由度并联机器人机构的各条支链所有可能的运动副组合以及它们的空间几何条件 .利用这一方法 。

矿山爆破机器人运动学分析与轨迹规划

为了提高矿山爆破机器人在抓取搬运炸药时的精度和平稳性,以五自由度机械臂为研究对象,研究了机械臂轨迹规划方法。首先,在SolidWorks中建立三维模型,通过D-H参数法建立运动学模型,并完成正逆运动学分析;然后,运用五次多项式插值法进行轨迹规划;最后,在MATLAB中进行仿真。仿真结果表明,角位移、角速度、角加速度变化曲线连续平滑无突变现象;该方法能够有效地规划五自由度机械臂的运动轨迹,提高其在抓取、搬运炸药时的工作效率。

新型5自由度并联机床运动控制算法研究

在分析 5 UPS/PRPU 5自由度并联机床机构的基础上 ,介绍了并联机床运动控制的基本原理 ,确定了具体的运动控制算法 ,将输入控制系统的数控刀位数据转化为驱动轴的控制指令 ,从而实现对机床加工过程中刀具位姿的控制。根据该算法编制的数控软件已成功地应用于实际的并联机床控制 ,取得了较好的效果。

5-UPS/PRPU五自由度并联机床静力学分析

介绍了 5 -UPS/PRPU五自由度并联机床机构 ,通过对该机构进行静力学分析 ,建立了该机床的静力平衡方程和静力传递矩阵。对机床加工过程中的受力进行了具体分析 ,根据作用在动平台上的外力负载 ,可以得到 5个驱动杆的受力大小和中间分支所承受的力偶矩大小 ,为该机床的结构设计。

钢丝绳传动5自由度机器人机构设计

提出一种用于物流系统的5自由度移动机器人系统,并对系统组成与功能进行了详细讨论。该系统机械臂由一种简洁高效的新型钢丝绳传动机构构成——行星8字形缠绕方式,整个结构紧凑高效,在减轻质量的同时提高对外做功的能力,并且解决了环形缠绕会产生的运动耦合联动问题,同时增加了关节的运动范围。还介绍了该系统的其他一些具体结构,如手部的丝杠螺母结构、钢丝张紧结构等。该新型钢丝绳传动结构在机器人研究方面具有一定的参考价值。