晶格型模块化软体机器人自重构序列

设计了一种基于膨胀-收缩运动规则的晶格型自重构模块化软体机器人.机器人由多个软体模块组成,每个软体模块由呈正六面体构型的硅胶主体和主从对接面组成.软体模块内部的凸起设计使其具有良好的膨胀性能,主从对接面是由与硅胶主体螺纹连接的铁盘、吸盘式电磁铁组成.基于软体模块体积变化与内部压强的关系式,对软体模块的充气膨胀进行分析,建立了充气气压与软体模块膨胀量之间的映射关系,获得相邻两软体模块连接所需的充气气压.每个软体模块在工作气压为30 kPa的情况下能够膨胀1.5倍,使用电磁铁连接及软体模块的膨胀-收缩运动规则实现相邻两软体模块的对接与分离,多个相邻软体模块的依次对接和分离可以实现模块化软体机器人的自重构.通过软体机器人自重构实验验证机器人自重构的可行性.     

M~2Sbot自重构机器人系统的拓扑自动表达

本文基于M2Sbot自重构机器人系统提出了拓扑构型的自动表达方法.根据单元模块本身的机械结构特性,对其进行了拓扑构型的简化,定义了各连接面与空间角度信息;分析了模块间可能的连接与连接方位,以有界深度优先搜索算法实现整体系统逻辑地址的自动定义,空间信息的自动描述以及系统中连接信息的自动表达.该表达方法能够准确描述自重构系统的连接信息与空间位姿,克服了现存的拓扑表达方法在存在回路的构型表达中的无解难题,为系统的重构算法与运动控制算法研究提供了一定的理论基础.     

分布式群体飞行机器人对接系统设计及自组装控制策略

介绍了一款由多个机器人模块组成的分布式群体飞行机器人系统DSFR(DSFR,Distributed Swarm Flying Robot),机器人模块可以在地面自主移动,相互自组装并形成一个整体的机器人构型进行空中飞行.文章主要介绍了DSFR的对接系统设计和自组装控制策略,提出了一种用于机器人构型描述的广义邻接矩阵.在对接系统的设计和构型描述矩阵的基础上,通过DSFR机器人的自组装控制实验展示并验证了相关设计和控制策略的可行性.     

混合型自重构机器人的结构设计及运动描述

设计了一种新型的混合型自重构模块化机器人.该机器人由多个相同的呈三棱柱状的主从式基本模块组成,每个主模块包括3个主驱动电动机及齿轮传动装置,每个从模块包括2个从驱动电动机及齿轮-齿条传动装置.根据齿轮、齿条不同运动速度,分析了该自重构机器人相邻2个基本模块中从模块的轴插入主模块的孔中完成对接动作的过程.基于基本模块的几何特征,描述了该自重构机器人的基本空间构型,最后仿真实现了该机器人从直线型变形为正六边形的过程.仿真结果表明,混合型自重构机器人基本模块结构设计紧凑,能对接和脱离,实现机器人的变形过程.     

基于拓扑结构的自重构模块化机器人重构策略的研究

为实现模块化机器人的高效控制与对接,在基于有向图的图论拓扑描述和连接矩阵的数学拓扑描述基础上,提出了一种新型的自重构机器人模块拓扑描述综合矩阵,它能准确的表达了机器人模块的连接方式和转角状态信息;利用综合矩阵可以找到构型的根节点,并以根节点为起点利用DFS(Depth-First-Search)得到初始构型与目标构型新的综合矩阵.并对两矩阵进行对比进而得出同构部分与重构部分.按照重构策略仅对重构部分进行重构得到目标构型.减少了参与重构的模块的数量并提高了重构效率,最后利用webots软件对模块化机器人进行仿真来验证重构策略的有效性和可行性.     

可重构机器人多模块组合越障研究

针对一种具有独立运动自由度的新型模块化可重构机器人,利用对偶四元数描述其各个模块空间位姿.对偶四元描述机器人重构前后的各模块位姿信息,相对齐次坐标矩阵在数学形式上更为简洁统一,方便获取模块之间转角状态、连接面关系及连接方位关系等信息.以多个模块机器人攀越台阶障碍为例,应用对偶四元数描述方法分析该机器人越障过程中各模块空间姿态、越障高度,结合电机选型与重心位置得出该组合构型越障的最大高度.仿真实验验证了对偶四元数描述方法在分析模块化可重构机器人空间位姿中的实用性与所提出的组合越障方法的可行性.     

电力铁塔攀爬机器人的步态分析

为了提高电力系统的自动化水平,减轻电力工人在检修高压输电系统时的劳动强度,同时保障其人身安全,提出并设计了一种可以攀爬电力铁塔的5自由度关节式机器人,给出了机器人的CAD模型,分析了其在铁塔两种位置攀爬过渡的能力.根据机器人机构特征,提出、分析和比较了蠕虫式和扭转式攀爬步态.蠕虫式攀爬步态即机器人本体的两连杆之间角度周期变化,两爪交替前进;扭转式攀爬步态即机器人本体不动,爪部回转关节旋转180°使得机器人整体扭转半周.在机械系统动力学仿真软件ADAMS环境下,对机器人采用这两种步态在铁塔主材表面、横担侧面和上表面3种方位攀爬情况进行了仿真,计算和分析了不同情况下机器人各关节转矩和系统能耗,得出最适合铁塔各种方位的攀爬步态:在横担上攀爬时应采用能耗较小的扭转式步态,但是在主材表面攀爬时两种步态能耗接近,需考虑障碍类型选取合适的步态.仿真结果为机器人的攀爬步态规划及控制策略提供了依据,同时样机试验结果也验证了两种攀爬步态的可行性.     

自重构机器人空间重构规划策略研究

本文基于链式自重构机器人提出了一种无标号、分布式的空间重构规划策略,研究自重构机器人的构型表达和空间重构运动.首先对自重构机器人进行了拓扑的描述,然后建立坐标系,描述整个机器人的空间状态,将重构理论从构型重构拓展到空间运动规划,来处理未知非结构环境下全局检测、控制与定位问题.最后介绍了重构规划的方法,并通过Webots对五个模块的自重构机器人系统变形进行仿真,证明了上述方法的有效性和可行性.     

自重构机器人辅助自重构规划策略研究

针对仅仅依靠初始构形组成模块间的相互协调运动无法完成自重构任务这一情况,结合DL-Cube(Double L Cube)自重构机器人单元模型的结构特性,设计构建了风车形子单元,该子单元具有移动、转变模块方位、携带模块等能力.提出了基于公共拓扑的自重构规划策略,即在进行自重构之前利用分级优化机制搜索出初始构形与目标构形之间的最大公共拓扑,然后以此公共拓扑为目标构形的生长中心,同时,借助于风车形子单元移动、转变模块方位及携带模块的能力,最终实现目标构形的重构.利用仿真实验验证了上述理论的有效性和可行性.     

基于构件的开放式机器人控制软件设计

提出了一种基于构件的模块化设计方法,将控制软件分成主视图、参数配置与数据存储、运动控制、数据通信、传感器数据采集与处理、外围接口和任务调度七个独立的基本功能模块.各模块都是根据机器人系统的共性总结抽象而成,采用标准的通信协议并提供开放式接口.任务调度模块可以通过读取配置文件将它们组合起来,让机器人系统完成特定的任务要求.这种设计模式可以提高机器人控制软件的可重构性以及系统开发效率.     

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.     

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.     

A computer generator for randomly layered structures

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

Perspherical Approaches for Electrons in Atoms and Charged Excitons in Quantum Wells

Instead of following Fock’s expansion,we solve the Schrodinger equation for some quantum mechanical manybody systems such as electrons in atoms and charged excitons in quantum wells in a similar way in hyperspherical coordinates by expanding the wave functions into orthonormal complete basis sets of the hyperspherical hannonics(HHs)of hyperangles and generalized Laguerre polynomials(GLPs)of the hyperradius.This leads the equation to     

Advances in broadband wireless communications under high-mobility scenarios

Future mobile communication systems aim at providing very high data transmission rates, even in high-mobility scenarios such as high-speed wheel-track trains, maglev trains, highway vehicles, airplanes, guided missiles or spacecraft. A particularly important commercial application is the strong and increasing worldwide demand for high- speed broadband wireless communications （up to 574.8 km/ h test speeds or 380 km/h commercial speeds） in railways, providing data, voice and video services for applications such as onboard entertainment services to passengers, train control, train dispatch, train sensor status handling and sur- veillance. In such high-mobility scenarios, there are a number of communication challenges, including fast hand- over, location updating, high-speed channel modeling, estimation and equalization, anti-Doppler spreading tech- niques, fast power control, and dedicated network architec- ture. Because signal transmission in very high-speed scenarios will inevitably experience serious deterioration, it is imperative to develop key broadband mobile communi- cation techniques for such high-speed vehicles.     

Wuhan University Journal of Natural Sciences TOTAL CONTENTS

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海南岛地体及其毗邻陆缘晚中生代—新生代古地磁研究和构造演化

本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。     

Scale-based spatial data model for GIS

Being the primary media of geographical information and the elementary objects manipulated, almost all of maps adopt the layer-based model to represent geographic information in the existent GIS. However, it is difficult to extend the map represented in layer-based model. Furthermore, in Web-Based GIS, It is slow to transmit the spatial data for map viewing. In this paper, for solving the questions above, we have proposed a new method for representing the spatial data. That is scale-based model. In this model we represent maps in three levels: scale-view, block, and spatial object, and organize the maps in a set of map layers, named Scale-View, which associates some given scales.Lastly, a prototype Web-Based GIS using the proposed spatial data representation is described briefly.     

Exciton Seebeck in Molecular Systems

Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with     

Achieving Unusual States of Matter Under High Pressure

The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to