可重构星球探测机器人的运动学建模及轨迹规划

提出了可重构星球探测机器人的概念，对系统中子机器人的研究进行了重点论述．通过设计恰当的子机器人连杆坐标系，利用Denavit-Hartenberg方法完成了子机器人的运动学建模，并直接给出了子机器人的运动学正解模型．由于使用单一的求解算法不能求出工作空间的封闭解，因此综合利用代数法、几何法原理及空间投影关系，结合子机器人的结构特殊性推导出了运动学逆解，从而得到了工作空间内的所有解．在此基础上，考虑结构间的约束关系，给出了子机器人的工作空间及轨迹规划方法．最后，使用OpenGL对设计的子机器人系统进行了运动学仿真实验，实验以末端操作器的直线运动为例，充分考虑空间几何的关系，其结果有效地证明了建模及轨迹规划的正确性。     

六自由度机器人3D建模仿真研究

由于多关节机器人是一个结构复杂的运动学系统,高仿真的多关节3D机器人难以快速实现。为解决仿真时的视觉失真,设计并实现了一种以D-H模型为核心的机器人3D仿真方法。以KUKA_5arc六自由度机器人为研究对象,采用Auto CAD与Matlab建立贴近实际的机器人运动学仿真模型,验证了3D建模的精确性、正逆运动学定位算法的正确性以及路径规划等动作的合理性,为改进机械结构与控制算法提供了依据。该方法能实现六自由度机器人的3D建模仿真。     

六自由度机械臂运动轨迹自动生成方法仿真与实现

运用运动捕捉系统,结合机器人运动学方法,提出一种六自由度机械臂运动轨迹自动生成方法.首先,在运动捕捉系统下得到人手臂末端的Marker标记点的位姿信息;然后,通过数据处理得到标记点的位姿矩阵,并将其作为机械臂末端执行器的位姿矩阵,进而通过数据流通道将该数据传入机器人运动学仿真系统,在仿真系统中运用代数解法求机器人运动学逆解,并进行运动学仿真.最后,将逆解求得的6个关节角度传入机械臂本体,实现机械臂末端执行器按照运动捕捉系统下手臂末端标记点的运动轨迹而运动.仿真实验表明:该方法具有可行性.     

基于机器人系统的3M技术研究

介绍了机器人系统在3M技术中的应用,并详细介绍了机器人系统的关键技术:机器人标定技术、机器视觉技术和离线编程技术。经过标定后机器人系统绝对精度大幅度提高,可满足机器人"手持"测量工具进行测量的需要,同时通过机器人模型和运动学方程,将测量数据建模,生成统一世界坐标系下的加工路径,将生成的加工路径通过离线编程技术转化成机器人系统的运动指令,控制机器人进行加工,因此机器人系统在测量、建模和加工过程中发挥了非常重要的作用。同时介绍了一种机器人系统在3M技术中的典型应用,并开发了智能测量、建模及加工机器人一体化系统,该系统集成了透明件测量、自由曲面建模、机器人离线加工等先进技术,满足了用户需求,已经成功应用于透明件研磨抛光领域。     

一种焊接机器人运动学分析新方法

提出了一种焊接机器人的运动学新方法.基于共形几何代数框架内的刚体运动表达,求解了焊接机器人的运动学正解.采用几何体外积运算获得了各关节点位置;通过几何体的内积运算以及简单的代数计算,获得了各关节角符号形式的余弦表达,从而获得该机器人运动学逆解的所有解析解.最后,以一种焊接机器人运动学为数字实例对新算法进行验证.结果表明,方法几何直观性好,计算简洁.     

MOTOMAN-HP3型机器人运动学建模

根据MOTOMAN-HP3型机器人具体结构特点,建立机器人的运动学模型,求出正逆解.并在机器人运动学建模过程中,对关节运动范围的转换规律进行了研究.为机器人运动分析、离线编程、轨迹规划等打下了基础.     

机器人三维图形仿真系统的设计

本文阐述了机器人三维动画仿真系统Ｒ３ＤＡＳＳ的设计原理。根据形体建模中综合代数法与离散法的优点，提出了ＤＡ法，兼顾了精确造型的可能性和运动仿真的实时性。同时结合造型系统的情况，提出了一种运动学方程的建立方案，避免了繁琐的输入Ｄ－Ｈ参数的步骤及矩阵求逆运算。     

基于Matlab/Simulink的机器人仿真平台分析

随着计算机的发展,仿真逐步成为当今重要研究工具,它为开发者提供强大的可视化功能。仿真技术也在机器人领域中发挥非常重要的作用,可用于运动学和动力学分析,离线编程,控制算法设计,机器人机械结构设计,机器人工作单元和生产线设计等。Matlab是目前应用最广泛的用于系统建模和仿真的开发平台。本文以一个三自由度机器人作为示例,在MATLAB/Simulink环境中进行建模和仿真分析,重点介绍了Matlab里有四类仿真工具的功能和特点,最后进行了对比分析。     

基于OpenGL的工业化机器人仿真研究

以工业机器人仿真系统为背景,介绍了机器人的发展历程,重点描述了工业化机器人仿真开发的方法。该方法掌握较为容易,开发成本低,具有良好的可扩展性。在此基础上,文章设计并实现了基于OpenGL的工业机器人仿真系统,包括虚拟仿真环境的搭建、运动学分析和三维模型的绘制。最后,研究了OpenGL在机器人图形仿真系统中的具体应用通适代码封装使得工业机器人图形建模变得简易可行,并分析了工业机器人系统结构。探讨了该系统的运动学和逆运动学实现方法,取得了良好的效果。该仿真系统的研究方法也能够为其他场合的应用提供一定的参考价值。     

一种新型欠驱动型并联机器人的运动学分析与仿真

传统并联机器人具有自由度数量与驱动电机数量相等的问题,效率低下。为解决这些问题,提出了一种基于传统并联机器人的新型欠驱动型并联机器人。分析了欠驱动型并联机器人的结构特点与工作原理,应用空间解析几何与向量代数法,推导了机器人的运动学正解与反解。建立了运动学模型,应用MATLAB验证了运动学正解与反解的正确性,确立了最优工作空间。仿真结果表明,驱动电机数量为3时实现了机器人3或4自由度切换的功能,提高了机器人的抓取效率,具有工作空间大、运行速度快、定位精度高、制造成本低等特点,具有广泛的工业应用前景。     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3～4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰～ -7.8‰, PDB) and matrix dolomites (-6.6‰～ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084～0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078～0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

A computer generator for randomly layered structures

AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…     

An Index mechanism for multi-scale view in spatial databases

There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.     

Jane Eyre——A Feminist In The 19th Century

In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-