基于DELTA机器人的研究与设计

针对传统DELTA机器人工作空间较小的问题,本文设计出一种利用滚珠丝杠形成曲柄滑块机构代替机器人减速器的新型DELTA机器人,并通过搭建机器人模型、对机器人进行运动学分析以及工作空间比较分析,得出该机器人具有工作空间大的优点.     

多关节机器人工作空间的分析与评价方法

本文运用 H-D 变换的基本原理,结合极坐标变换导出了产生n自由度多关节机器人工作空间的递推算法,当给定了机器人的结构尺寸,即可将机器人工作空间在一特定平面内的边界图形用计算机打出并计算出机器人工作空间容积。在本文的另一部分介绍了两种计算机器人工作空间的性能指标,最后用几个机器人的结构参数进行计算和讨论。     

基于MATLAB的工业机器人工作空间分析及图形仿真

在对机器人运动学分析和误差补偿方案建立的基础上,提出用数值法对与测量机器人连接的工业机器人的工作空间进行求解。对六自由度串联机器人的工作空间进行了MATLAB三维图形仿真,同时分析介于测量机器人和工业机器人之间的联动装置的球面副转角,研究球面副转角对工业机器人工作空间的影响情况。     

基于MRI的胸腹部介入治疗机器人工作空间分析

机器人工作空间的分析和求解是机器人机构设计过程中一个非常重要的问题,本文基于Matlab仿真法研究MRI环境下的胸腹部介入治疗机器人的工作空间,根据机器人结构,利用Matlab／Silnulink中的SimMechanics工具箱进行建模,并仿真出机器人的工作空间,最后通过仿真结果验证机器人结构的合理性井对机器人结构的优化设计提出想法。     

机器人灵活工作空间的边界分析

机器人灵活工作空间的分析是机器人运动学至今没有解决的一个问题.由于机器人在灵活工作空间中工作不会受到本身机构对它的限制.所以,机器人灵活工作空间的大小对于提高机器人的操作性能就显得格外重要.本文旨在解决机器人灵活工作空间边界的计算问题.首先.它分析了灵活工作空间边界的性质;其次,用一种新的方法——网络跟踪法确定了灵活工作空间在横截面内的边界;最后.提出了灵活工作空间端边界的求解方法.     

机器人工作空间的数值计算

本文给出了计算任意结构形式任意自由度单链机器人工作空间的数值方法。这种方法把计算机器人工作空间的极限距离、边界曲线和边界曲面问题转化为求满足一定约束条件下的极值问题。通过选用不同的目标函数和约束条件就可以求出机器人工作空间边界曲面上的一系列特征点,把这些点连成线或面就构成了机器人的工作范围.根据上述讨论本文编制了计算机器人工作空间的程序软件 WZ,只要输入机器人的结构参数和各自由度的运动范围就可以求出机器人工作空间边界曲面上的若干点,并用绘图机绘出边界曲线。     

机器人操作臂工作空间的混合计算方法

机器人操作臂工作空间的形状和体积的精确计算对于其优化问题是非常重要的。为此首先根据从关节空间到工作空间的运动映射关系,使用蒙特卡洛方法产生由点组成的三维机器人工作空间。然后,通过把这些点分解成一系列的切片,获得机器人工作空间每层的二维边界曲线;基于切片曲线,由三维重构的方法产生边界曲面。最后,用数值积分的方法计算了机器人工作空间的体积。     

基于计算的工业喷涂机器人基本参数设计方法

设计与确定机器人参数需要在各项性能之间进行折衷,常常是一个耗时的迭代过程。本文提出了一种工业喷涂机器人基本参数确定的一般方法。通过喷涂机器人的设计与开发过程,基于机器人建模方法,归纳出机器人基本参数对各项性能尤其是工作空间特性的影响因素与规律,并在此过程中上分析了其结构参数对机器人工作空间和性能的影响,从而得出了机器人工作空间特性与结构参数之间的内在联系,为工业机器人的设计提供依据。     

松协调下双臂机器人的协作工作空间计算

分析了松协调下双臂机器人的协作工作空间，介绍了一种计算双臂机器人协作工作空间的数值方法。在该方法基础上，利用LINGO软件确定双臂机器人的协作工作空间的界限曲面和极限位置。     

基于AutoCAD平台的六自由度并联机器人

本文研究基于AutoCAD平台的六自由度并联机器人在姿态给定情况下工作空间(即位置工作空 间)的几何确定方法,该方法以机器人的运动学反解为基础,得出Stewart并联机器人和6-R TS并联机器人位置工作空间的边界方程,从而得出Stewart并联机器人的位置工作空 间是6个球体的交集,6-RTS并联机器人在姿态给定时其工作空间是6个相同的规则曲面体 的交集．基于AutoCAD平台,其交集以及交集的容积可以很容易的得出,该方法是确定六自 由度并联机器人工作空间的一种简单、有效方法．     

A level-set method for vibration and multiple loads structural optimization

We extend the level-set method for shape and topology optimization to new objective functions such as eigenfrequencies and multiple loads. This method is based on a combination of the classical shape derivative and of the Osher–Sethian level-set algorithm for front propagation. In two and three space dimensions we maximize the first eigenfrequency or we minimize a weighted sum of compliances associated to different loading configurations. The shape derivative is used as an advection velocity in a Hamilton–Jacobi equation for changing the shape. This level-set method is a low-cost shape capturing algorithm working on a fixed Eulerian mesh and it can easily handle topology changes.     

A shape design system using volumetric implicit PDEs

Solid modeling based on partial differential equations (PDEs) can potentially unify both geometric constraints and functional requirements within a single design framework to model real-world objects via its explicit, direct integration with parametric geometry. In contrast, implicit functions indirectly define geometric objects as the level-set of underlying scalar fields. To maximize the modeling potential of PDE-based methodology, in this paper we tightly couple PDEs with volumetric implicit functions in order to achieve interactive, intuitive shape representation, manipulation, and deformation. In particular, the unified approach can reconstruct the PDE geometry of arbitrary topology from scattered data points or a set of sketch curves. We make use of elliptic PDEs for boundary value problems to define the volumetric implicit function. The proposed implicit PDE model has the capability to reconstruct a complete solid model from partial information and facilitates the direct manipulation of underlying volumetric datasets via sketch curves and iso-surface sculpting, deformation of arbitrary interior regions, as well as a set of CSG operations inside the working space. The prototype system that we have developed allows designers to interactively sketch the curve outlines of the object, define intensity values and gradient directions, and specify interpolatory points in the 3D working space. The governing implicit PDE treats these constraints as generalized boundary conditions to determine the unknown scalar intensity values over the entire working space. The implicit shape is reconstructed with specified intensity value accordingly and can be deformed using a set of sculpting toolkits. We use the finite-difference discretization and variational interpolating approach with the localized iterative solver for the numerical integration of our PDEs in order to accommodate the diversity of generalized boundary and additional constraints.     

新型6-HTRT并联机器人工作空间和参数研究

本文介绍了新型6-HTRT并联机器人的机构型式和工作原理，给出了考虑到约束条件的 位置逆解算法和存在多组解时的逆解选取准则．利用逆解算法和三维搜索，得到了确定该类 型机器人工作空间的方法和工作空间体积的计算公式．分析了6-HTRT并联机器人工作空间 的形态特点以及机器人结构参数和运动参数对工作空间体积的影响．     

基于遗传算法模式匹配的机器人实时视觉伺服

对于机器人手臂来讲 ,对工作环境的识别是完成一个智能任务的最重要的问题之一 .因为这种智能可以使它工作在一个变化的环境中 .本文提出了一种新的机器人手臂的控制策略 ,可以利用视觉信息来指导机器人的手臂在它的工作空间中捡起一个已知形状但任意位置和方向的物体 .在对物体的搜索过程中 ,利用基于视觉闭环的视觉伺服来完成对机器人手臂的运动控制 .本系统利用遗传算法 (Genetic Algorithm ,GA)和模式匹配技术完成对搜索空间的搜索并获得了良好的结果 .本文完成了对带有两连杆手臂的视觉伺服系统的仿真 ,仿真结果证明了算法的有效性     

空间望远镜主镜的主动支撑面形校正分析

大型空间望远镜的主镜由于受重力、温度和装配等因素的影响,会产生面形误差,影响光学系统的成像效果。为了提高空间望远镜主镜对重力、温度的适应性,采用400mm弯月镜进行了主动支撑面形校正研究。主动支撑方案由3个固定支撑和7个主动支撑构成,利用Zernike系数和最小二乘法计算力促动器的校正力大小。使用有限元仿真软件分析了镜子在重力工况和稳态温度工况下,校正前后的面形结果。分析结果显示,采用本文的主动支撑方案,各工况下被校正后的主镜面形精度达到均方根(RMS)值<λ/20的设计指标,面形质量有明显的提高。同时,在重力工况中引入了实际装调中可能存在的安装误差等因素,仿真结果显示装配误差对校正结果影响较小,说明主动支撑系统具有较高稳定性。     

Evaluating shape correspondence for statistical shape analysis: a benchmark study

This paper introduces a new benchmark study to evaluate the performance of landmark-based shape correspondence used for statistical shape analysis. Different from previous shape-correspondence evaluation methods, the proposed benchmark first generates a large set of synthetic shape instances by randomly sampling a given statistical shape model that defines a ground-truth shape space. We then run a test shape-correspondence algorithm on these synthetic shape instances to identify a set of corresponded landmarks. According to the identified corresponded landmarks, we construct a new statistical shape model, which defines a new shape space. We finally compare this new shape space against the ground-truth shape space to determine the performance of the test shape-correspondence algorithm. In this paper, we introduce three new performance measures that are landmark independent to quantify the difference between the ground-truth and the newly derived shape spaces. By introducing a ground-truth shape space that is defined by a statistical shape model and three new landmark-independent performance measures, we believe the proposed benchmark allows for a more objective evaluation of shape correspondence than previous methods. In this paper, we focus on developing the proposed benchmark for $2$D shape correspondence. However it can be easily extended to $3$D cases.     

形状空间中模型变化的插值生成

在形状空间中,由三角形网格构成的模型可视为空间中的一个点,可以借助黎曼度量对形状空间进行操作,从而实现对模型的变换.改进了已有的操纵形状空间的方法,根据输入模型顶点的位置变化判断是否需要利用黎曼度量计算插值位置,降低了形状空间的维数,提高了运算速度.实验结果显示,混合利用线性插值和利用形状空间计算2种方法的生成模型具有良好的效果.     

Geometric Flows of Curves in Shape Space for Processing Motion of Deformable Objects

We introduce techniques for the processing of motion and animations of non‐rigid shapes. The idea is to regard animations of deformable objects as curves in shape space. Then, we use the geometric structure on shape space to transfer concepts from curve processing in ?ⁿ to the processing of motion of non‐rigid shapes. Following this principle, we introduce a discrete geometric flow for curves in shape space. The flow iteratively replaces every shape with a weighted average shape of a local neighborhood and thereby globally decreases an energy whose minimizers are discrete geodesics in shape space. Based on the flow, we devise a novel smoothing filter for motions and animations of deformable shapes. By shortening the length in shape space of an animation, it systematically regularizes the deformations between consecutive frames of the animation. The scheme can be used for smoothing and noise removal, e.g., for reducing jittering artifacts in motion capture data. We introduce a reduced‐order method for the computation of the flow. In addition to being efficient for the smoothing of curves, it is a novel scheme for computing geodesics in shape space. We use the scheme to construct non‐linear “Bézier curves” by executing de Casteljau's algorithm in shape space.     

基于整数维约束的分维形状映射生成方法

把整数维图形研究方法与分数维图形研究方法相结合，提出一种基于整数维规则几何形状的约束的分维形状映射生成方法，有于描述自然界和工程中出现的且具有特定基本形状趋势的随机现象和随机过程，首先，任意选取一个具有调配函数的自由形状构造一个有序参数空间，确定有序参数的取值规律和区域，把有序参数空间与自适应神经网络，随机性相结合，构造一个随机离散参数空间，并建立起有序参数与随机离散参数之间的参数对应关系，最后，通过有序与无序的参数对应关系，建立一个独立于任意规则几何形状的统一的分形映射关系，对相应整数维的任意规则参数几何形状分形映射，生成宏观形态趋势可预见和可控制的分维形状，该提出的方法适有于任意参数几何形状的分形映射，生成分形图形，且方法简明，易于实现。     

Dynamic Multi‐View Exploration of Shape Spaces

Statistical shape modeling is a widely used technique for the representation and analysis of the shapes and shape variations present in a population. A statistical shape model models the distribution in a high dimensional shape space, where each shape is represented by a single point. We present a design study on the intuitive exploration and visualization of shape spaces and shape models. Our approach focuses on the dual‐space nature of these spaces. The high‐dimensional shape space represents the population, whereas object space represents the shape of the 3D object associated with a point in shape space. A 3D object view provides local details for a single shape. The high dimensional points in shape space are visualized using a 2D scatter plot projection, the axes of which can be manipulated interactively. This results in a dynamic scatter plot, with the further extension that each point is visualized as a small version of the object shape that it represents. We further enhance the population‐object duality with a new type of view aimed at shape comparison. This new “shape evolution view” visualizes shape variability along a single trajectory in shape space, and serves as a link between the two spaces described above. Our three‐view exploration concept strongly emphasizes linked interaction between all spaces. Moving the cursor over the scatter plot or evolution views, shapes are dynamically interpolated and shown in the object view. Conversely, camera manipulation in the object view affects the object visualizations in the other views. We present a GPU‐accelerated implementation, and show the effectiveness of the three‐view approach using a number of real‐world cases. In these, we demonstrate how this multi‐view approach can be used to visually explore important aspects of a statistical shape model, including specificity, compactness and reconstruction error.