六自由度机械手三维可视化仿真研究

针对Reniovo型六自由度机械手的特定构型,分析了机械手的基本结构,用D-H方法建立了其运动学模型,并推导了基于解析法的机械手正、逆运动学求解方法,针对运动学逆解,推导了基于多解自动寻优的方法,提高了机械手的可行工作空间和避碰能力,最终在运动学求解基础上设计了机械手的运动轨迹规划算法。此外,利用3ds Max进行机械手三维建模,并利用Open Gl技术实现机械手三维运动显示,以三维可视化仿真的方式对机械手的逆解及轨迹规划算法进行了仿真验证,仿真结果显示仿真机械手可以准确执行预期轨迹并达到预定的位姿,证明了上述的仿真方法对于研究机械手工作原理、工作空间及进行碰撞检测都具有参考意义。     

五指形仿人机械手的设计与实现及示教

设计和实现了一个具有五个手指和手掌的仿人机械手（以下简称仿人机械手）,并利用数据手套对其进行了示教,使其能有效地完成复杂的作业。首先,以现有的仿人机械手研究成果为基础,对仿人机械手进行了优化设计和实现;然后,以数据手套为示教源,对仿人机械手示教模型进行了研究,采用D-H变换矩阵建立了仿人机械手的逆向运动学,解决了示教运动映射问题。最后,利用仿人机械手进行了若干作业实验,实验结果证明了仿人机械手及其示教模型的正确性。     

机械手的运动学分析及在屏幕贴合中的应用

在机械手屏幕贴合项目中,以6关节机械手RV-2F为研究对象,分析结构和连杆参数,采用改进D-H法建立各连杆坐标系和机械手的运动学方程;运用MATLAB Robotics Toolbox建立RV-2F机械手模型,进行关节空间轨迹规划与仿真,实现并分析机械手高速运行的平稳性,满足应用要求。     

全方位移动机械手路径规划仿真平台的设计

机器人的三维仿真在机器人的研究中起着重要作用,论文以实验室中的全方位移动机械手为背景,建立了该移动机械手的运动学模型,然后利用VisualC++调用OpenGL建立了移动机械手的三维模型及路径规划的仿真平台,给出了实现算法,为移动机械手路径规划算法的研究提供了更为生动形象的仿真平台。     

五指形仿人机械手的数学模型研究

以人手的解剖学研究成果为基础，对具有五个手指和手掌的仿人机械手（以下简称仿人机械手）的数学模型进行研究。首先，以现有的工业机器人研究成果为基础，提出了仿人机械手的坐标系建立方法。然后，从人手的解剖学特点出发，采用D—H变换矩阵建立了仿人机械手运动学模型。     

六自由度机械手三维运动仿真研究*

以六自由度机械手三维运动仿真为背景,介绍了利用OpenGL实现机械手运动仿真的有效方法,重点分析了机械手运动学模型的构建以及运动轨迹规划的实现。对于一般的机械手运动仿真系统,该实例具有一般普遍性。     

OpenGL在机械手三维运动仿真中的应用

该文介绍了OpenGL的功能及其实现三维动态仿真的原理与过程,并以一个多自由度机器人机械手为例,对它的结构进行了简化并建立了其运动学模型。重点讲述了用OpenGL实现三维运动仿真的基本方法及其实现,认为在仿真过程中采用“双缓冲技术”能得到平滑的动画,并分析了“双缓冲技术”的实现技术。本文对机械手的结构进行了简化,将机械手的每一个连杆看成一个子体,提出用“堆栈矩阵”法来解决运动仿真时多子体运动的继承性问题,为多自由度机械手的三维运动仿真提供了一种新的方法。     

N自由度机器人仿真的实现

对N自由度机器人进行了数学建模和仿真研究。构建了N自由度机器人的运动学数学模型，然后基于牛顿欧拉方程建立了机器人的动力学模型。用此种方法建立的模型随着自由度的增加，机器人模型的复杂程度相对其他方法来说增加较慢，迭代速度快。借助Matlab和Simulink强大的计算和绘图能力实现了N自由度机器人的运动轨迹的实时检测、运动学求解、动力学求解、轨迹生成、机械手动态演示等功能，可以用于机器人教学或使用机器人的工业环境中进行仿真演示或实时检测。具有较高的应用价值。     

基于ADAMS的欠驱动三指机械手虚拟设计及参数优化

针对现有一款模块化欠驱动三指机械手本身的结构特征不完善,所能实现的抓取任务、承载能力有限等问题,设计了一种弹簧被动自适应手指机构。根据欠驱动手指的结构、构件的尺寸、驱动规律及构件间相对关系,以单指为例采用D-H坐标法建立了运动学模型;利用ADAMS软件对该欠驱动手的3种抓取构型进行运动学仿真,验证了结构设计的合理性;在满足运动学模型准确性的前提下,选出1种抓取构型,以中心滑盘连接手指处所受应力最小为目标,对基指节内部推杆的长度及摆动的角度进行参数优化,有效地增强了欠驱动手抓取的多样性,可为该机械手的设计研究提供可靠的理论依据。     

多机械手系统建模的一般方法

以双机械手协调作业为例,介绍了多机械手系统建模的一般方法.对于不同数目的机械 手以及不同的作业任务,通过定义广义变量,建立关于广义变量的运动学和动力学方程,进而 获得多机械手系统的统一模型.它为多机械手系统的控制和仿真提供了基础.     

Derivation and analysis of a dynamic model of a robotic manipulator on a moving base

A dynamic model of a robotic manipulator mounted on a moving base is derived using the Euler-Lagrange approach. It is assumed that the base inertia is large enough not to be influenced by the manipulator motion and therefore can be treated as a time-varying parameter in the dynamic equations. The presented derivation is applied to a Mitsubishi PA10-6CE robotic manipulator mounted on a 2-DOF platform. The model is analysed by comparing simple closed-loop control results of the simulated model with experimental data from the manipulator mounted on the platform.     

Mobility properties of a Schoenflies-type parallel manipulator

This paper addresses the mobility properties of a novel Schoenflies-type parallel manipulator. By analyzing the degree of freedom (DoF) of the manipulator, we select a set of independent variables to describe the pose relationship of the manipulator and the fixed base, which is the least in number compared with others. Through coordinate transformation, we can obtain the geometric relationship in the absolute coordinate system via a set of parametric equations. As a result, the least order's Jacobian matrix will be gained and the singularity of the manipulator can be expressed as the determinate of the Jacobian matrix is zero. The distinctive merit of this methodology is that the order of Jacobian matrix is the least compared with others.     

Analysis and Control for an Omnidirectional Mobile Manipulator

This paper describes analysis and control for a holonomic omnidirectional mobile manipulator, in which the holonomic omnidirectional platform consists of three lateral orthogonal wheel assemblies and a mounted manipulator with three rotational joints is located at the center of gravity of the platform. We first introduce the kinematic model for the mobile manipulator and derive the dynamical model by using the Newton–Euler method, where a model which simultaneously takes account of features of both the manipulator and the mobile parts is given to analyze the effect of the movement of mounted manipulator on the platform. Then, the computed torque control and the resolved acceleration control methods are used to show that the holonomic omnidirectional mobile manipulator can be controlled so as to retain any end-effector position and orientation, irrespective of the direction of external applied force. The validity of the model and the effectiveness of the present mobile manipulator are proved by using several numerical simulations and 3D animations.     

Investigations on the dynamic coupling in AUV-manipulator system and the manipulator trajectory errors using bond graph method

This article presents the modelling and simulation of the dynamic coupling in an autonomous underwater vehicle (AUV)-manipulator system, used for subsea intervention tasks. Bond graph, a powerful tool in multi-domain dynamic system modelling, is used for the first time to model the coupled dynamics of the AUV-manipulator system. This method enables the development of the system model in a modular form by creating sub-system models and connecting these models together at energy interactions ports, thus overcoming many of the computational difficulties encountered in conventional modelling methods. The effects of gravity, buoyancy, added mass and fluid drag on the dynamics of a 3 degrees of freedom (DoF) manipulator mounted on a 6 DoF AUV are analysed. The manipulator trajectory errors due to the interaction forces and moments between the vehicle and the manipulator have also been investigated and the results are presented. The dynamic model predicts the reaction forces on the vehicle under various operating conditions of the manipulator and their influence on the manipulator trajectory. The percentage errors of manipulator tip trajectory for different initial configurations and operating conditions are analysed. The estimation of resulting errors in the manipulator path due to dynamic coupling effect on the manipulator trajectory helps in the design of suitable trajectory controller for the system. Cartesian space transpose Jacobian controller for trajectory control of manipulator has been implemented and results are presented.     

Symbolic modeling and dynamic simulation of robotic manipulators with compliant links and joints

The explicit, non-recursive symbolic form of the dynamic model of robotic manipulators with compliant links and joints are developed based on a Lagrangian-assumed mode of formulation. This form of dynamic model is suitable for controller synthesis, as well as accurate simulations of robotic applications. The final form of the equations is organized in a form similar to rigid manipulator equations. This allows one to identify the differences between rigid and flexible manipulator dynamics explixitly. Therefore, current knowledge on control of rigid manipulators is likely to be utilized in a maximum way in developing new control algorithms for flexible manipulators.

Computer automated symbolic expansion of the dynamic model equations for any desired manipulator is accomplished with programs written based on commercial symbolic manipulation programs (SMP, MACSYMA, REDUCE). A two-link manipulator is used as an example. Computational complexity involved in real-time control, using the explicit, non-recursive form of equations, is studied on single CPU and multi-CPU parallel computation processors.     

基于张拉整体结构的连续型弯曲机械臂设计与研究

为实现对目标物体的缠绕捕获，利用张拉整体结构质量轻、变形大等特点，提出一种基于张拉整体结构的连续型机械臂的设计．本文首先设计连续型机械臂的结构，建立其力学模型．通过准静态和动态分析，对不同驱动形式下的连续型机械臂运动进行仿真，并在实验平台上验证所建力学模型的准确性，最后分析了其工作空间及奇异位姿．实验结果表明本文设计的连续型机械臂可以实现弯曲缠绕变形，满足对不同大小物体进行缠绕捕获的需求．     

Dynamic modelling, simulation and control of a manipulator with flexible links and joints

The paper presents a dynamic modelling technique for a manipulator with multiple flexible links and flexible joints, based on a combined Euler–Lagrange formulation and assumed modes method. The resulting generalised model is validated through computer simulations by considering a simplified case study of a two-link flexible manipulator with joint elasticity. Controlling such a manipulator is more complex than controlling one with rigid joints because only a single actuation signal can be applied at each joint and this has to control the flexure of both the joint itself and the link attached to it. To resolve the control complexities associated with such an under-actuated flexible link/flexible joint manipulator, a singularly perturbed model has been formulated and used to design a reduced-order controller. This is shown to stabilise the link and joint vibrations effectively while maintaining good tracking performance.     

基于FBS拓展模型的可穿戴式康复机械手设计研究

康复机械手是康复医学和机器人技术的结合,其目的是通过外带辅助器具约束受伤肢体的运动 范围,重建手部的运动系统功能,从而对患者患肢进行康复治疗。对功能-行为-结构(FBS)模型进行拓展,以设 计知识流理论为出发点,融入用户需求和原理空间构建了基于 FBS 拓展模型的康复机械手设计方案。通过对 需求-功能-原理-行为-结构(PFWBS)迭代设计解耦,并结合手部的生物学结构,系统分析了康复机械手概念模 型映射过程。构建了康复机械手功构求解策略,为脑卒中患者设计了一款可穿戴式康复机械手,通过仿真分析 和工作空间求解,验证了康复机械手机构的合理性。结果表明,基于 FBS 拓展模型的映射求解策略为康复机 械手的设计研究提供了理论基础和实践策略,能有效提升用户体验。     

Robust Interaction Control of a Mobile Manipulator – Dynamic Model Based Coordination

This paper discusses the modeling and control of a spatial mobile manipulator which consists of a robotic manipulator mounted upon a wheeled mobile platform. The nonholonomic model, which assumes perfect contact between the wheels and the ground, is obtained using the Lagrange–d'Alembert formulation. Also, the dynamic model, which considers slip of the platform's tires, is developed using the Newton–Euler method and incorporates Dugoff's tire friction model. The complexity of the model is increased by introducing kinematic redundancy which is created when a multi-linked manipulator is used. The kinematic redundancy is resolved by decomposing the mobile manipulator into two subsystems; the mobile platform and the manipulator. Based on the coordination scheme used to resolve the kinematic redundancy, a robust interaction control algorithm, in which suitable controllers are designed for the two subsystems, is developed and applied. The adverse effect of the wheel slip on the tracking of commanded motion is discussed in the simulation. For the dynamic model, a robust control approach is employed to minimize the harmful effect of the wheel slip on the tracking performance. Simulation results show the promise of the developed algorithm.     

多移动机械臂系统动力学建模以及稳定性分析

随着社会生产力的发展和发展需求的提高,移动机械臂凭借着自身优势,受到学术界和工业界的广泛关注.但在许多工作场景下,单个移动机械臂有着自由度数以及载荷的限制,无法顺利完成任务.为了更好地满足任务需求,多移动机械臂系统应运而生.在上述工业背景下,本文建立了多移动机械臂系统的动力学模型,并针对该动力学方程进行了稳定性分析.首先通过拉格朗日方程建立单个移动机械臂的动力学方程,将多体动力学软件仿真结果同动力学模型数值计算结果进行对比,验证了模型的正确性.随后联立多个移动机械臂的动力学方程和操作对象的动力学方程,得到封闭形式的多移动机械臂系统的动力学方程.再利用关节位置误差和速度误差设计李雅普诺夫函数,通过反步法获得了关节力矩的控制律.最后在多体动力学软件仿真中,察看轨迹是否能跟踪上期望信号来检验控制律的有效性.