20 resultados para Eletric power transmission
em Chinese Academy of Sciences Institutional Repositories Grid Portal
Resumo:
介绍了一种超高压输电线路巡检机器人控制系统的设计与实现方法.根据巡检作业任务的要求,采用遥控与局部自主相结合的控制模式实现巡检机器人沿线行走及跨越障碍.设计了巡检机器人有限状态机模型,实现了机器人遥控与局部自主控制的有机结合.采用基于激光传感器定位的方法实现了巡检机器人的自主越障控制.实验结果表明,该机器人可实现沿线行走及自主跨越障碍,从而验证了控制系统设计的有效性与合理性.
Resumo:
巡检机器人在越障时,需要完成机器人手臂的准确抓线控制.结合输电线的几何特征和摄像机成像原理,提出了一种基于单摄像机的立体视觉方法来确定输电线的位置和姿态.基于该定位方法及视觉伺服理论,建立机械手抓线伺服控制模型.利用自行研制的巡检机器人进行了视觉伺服抓线实验;实验结果验证了该方法的有效性.
Resumo:
将两种基于传感器信息的导线定位方法的特点和差异进行了分析和对比,得出方法Ⅱ的解算能力强于方法Ⅰ的解算能力,但由于方法Ⅱ的定位精度低于方法Ⅰ的定位精度,因此,选用方法Ⅰ进行野外作业。
Resumo:
介绍了超高压输电线路巡检机器人越障控制方法。根据巡检作业任务的要求,采用遥控与局部自主控制相结合的方法,实现了巡检机器人沿线行走及跨越障碍的功能。采用基于单目摄像头定位和视觉伺服的方法,实现了巡检机器人的自主越障控制。实验结果表明,该机器人可沿线行走并自主跨越障碍,从而验证了控制系统设计的有效性与合理性。
Resumo:
给出了一种超高压输电线路巡检机器人控制系统的设计与实现方法.根据机器人的作业任务,提出了基于传感器信息、约束信息以及动作反馈信息作为输入,产生式系统作为动作输出的越障控制方式.仿真结果表明此方法对于机器人的越障过程是有效的.
Resumo:
探讨了基于分布式专家系统的超高压输电线路巡检机器人控制系统,给出了一种利用CUPS和C、VC++混合编程构成分布式专家系统作为机器人控制器的方法,并且提出了一种基于规则和证据的可信度(CF)的分布式专家系统的协调算法.经过试验论证,该控制方法能很好地实现超高压输电线路巡检机器人的作业功能。
Resumo:
输电线路巡检机器人是一种特种作业机器人,具有广阔的输电线路巡检的应用背景,该项研究是机器人学研究领域的前沿课题之一,而越障机构又是巡检机器人的关键技术之一。本文在863课题《超高压输电线路巡检机器人》的资助下,系统地研究了输电线路巡检机器人的移动越障机构及其理论建模,目的是分析综合越障巡检机构,研制新型的越障巡检机构;通过结构优化减小能耗提高机器人巡检线路的实用性。 本文首先系统研究了巡检作业的典型工况,建立巡检目标障碍空间的数学模型,为巡检机器人的越障巡检机构研究与越障规划奠定基础。 第二、建立特殊工况下的设计原则,研究越障巡检机构的分析与综合方法。1、提出一种基于障碍空间分析的越障巡检机构综合方法,在分析多种越障机构的越障原理与越障性能的基础上,基于螺旋理论进行越障巡检机构的型综合与数综合,优化越障巡检机构的自由度与构型,并且设计两种新型越障巡检机构。2、用影响系数法,建立机器人运动学模型,探讨越障巡检机构的运动综合。3、提出线上操作的打滑稳定裕度与摆动稳定裕度,且给出相应的判据。在建立静力学与动力学模型、探讨越障巡检机构的动力性能、分析操作手夹持姿态的稳定性的基础上,拓展夹持稳定性量度,提出打滑裕度与摆动裕度。 第三、建立特殊风载荷工况下,结构参数受风向和风压影响的数学模型,得到不同风荷载的风压对尺寸参数的影响;由风载荷影响操作手夹持稳定性,从而影响行走轮包角参数,分析得到相应的行走轮外缘包络包角范围。根据风荷载阻力与尺寸参数的关系,基于最小能量理论采用积分有限元分析,对机器人的重要零件与部件进行了结构参数优化。 第四、根据环境模型制定越障流程;分析越障过程的三个难点:机构平衡、导线辨识与定位可知,导线定位是越障的关键;并就如何定位导线的越障关键问题,提出一种解析定位方法,对比搜索定位方法可知,解析定位方法优于搜索定位方法。 第五、通过实验验证越障原理、越障规划、定位方法、及系统性能等。在调试和考机合格的基础上,分别在实验环境下验证了线上行走巡检原理的有效性和连续越障的可行性;在野外现场实验验证了越障巡检机器人系统的原理可靠性与越障定位的有效性。
Resumo:
近年来,机器人的应用越来越广泛和深入,输电线巡检机器人是当前特种作业机器人的研究热点之一,具有广泛的应用前景和实用价值。本文的研究内容是围绕国家“863”计划支持项目“500KV超高压输电线巡检机器人的研究”展开的。本研究工作针对巡检机器人的关键控制问题,主要由三部分组成:设计了巡检机器人的体系结构,并应用离散事件理论对机器人的任务、行为和动作建模;对巡检机器人双轮同步驱动控制进行了分析,并应用奇异摄动理论设计了控制器;研究了基于单目视觉的输电线立体定位方法及通过视觉伺服完成机器人自主抓线控制。 第一,介绍了巡检机器人的作业环境,重点探讨了机器人机械系统和控制系统的设计与实现。在机械子系统中,详细介绍了巡检机器人的机构实现与越障方法。在控制系统中详细阐述了基于分层递阶的机器人控制系统硬件组成。另外介绍了供电系统、无线传输系统、传感系统的设计与实现。分析了输电线路周围的电磁环境,及其对机器人的影响,并根据分析结果完成了对机器人的电磁防护设计。 第二,开展了输电线巡检机器人体系结构及人机交互系统研究,针对巡检机器人工作特点设计了基于规划和感知行为的混合式体系结构。针对巡检机器人工作环境设计了以机器人为中心的人机交互方式。参考前人建立的离散事件动力系统的层次结构和并行结构,提出了顺序结构并证明了其无阻塞性、可控性和监控器存在性,并结合以上三种结构建立了巡检机器人作业行为的离散动力学模型,分别获得了任务层、行为层和动作层的监控器。 第三,进行了巡检机器人双轮驱动控制研究。巡检机器人双轮行走机构为过驱动系统,对双轮行走系统进行了运动学和动力学建模,将一行走轮设为主动轮另一行走轮设为从动轮。针对两行走轮之间弹性关节导致的控制中的振荡问题,采用奇异摄动理论将系统分为快慢两个子系统;针对巡检机器人系统参数的时变性采用PD自适应算法设计了慢系统控制器;应用最优控制理论设计了快系统控制器。仿真结果验证了该方法的有效性。 第四,进行了输电线视觉定位和视觉伺服抓线问题的研究。输电线巡检机器人的自主越障控制是实现机器人实用化的关键问题。为实现巡检机器人自主越障,采用视觉伺服控制机械手臂自动抓线。为提取输电线图像特征点,针对输电线投影图像特征改进了边缘提取算法,应用聚类算法提取了输电线上的像素点。提出在机械手运动过程中采用EKF(扩展卡尔曼滤波)来实现对输电线的立体定位。在分析了当前基于图像的视觉伺服研究现状,建立了基于图像雅克比矩阵的输电线视觉伺服抓线模型。针对非标定状况下图像雅可比矩阵中的不确定参数,应用I&I(Immersion Invariant)自适应算法来实现无标定图像视觉伺服。针对机器人的动力学不确定性,设计了模糊自适应控制器,并证明了稳定性。仿真验证该方法的有效性,实验验证了基于视觉伺服的抓线控制的有效性。
Resumo:
Guangxi Longtan Hydropower Station is not only a representative project of West Developing and Power Transmission from West to East in China, but also the second Hydropower Station to Three Gorges Project which is under construction in China. There are 770 X 104m3 creeping rock mass on the left bank slope in upper reaches, in which laid 9 water inlet tunnels and some underground plant buildings. Since the 435m high excavated slope threatens the security of the Dam, its deformation and stability is of great importance to the power station.Based on the Autodesk Map2004, Longtan Hydropower Station Monitoring Information System on Left Bank has been basically finished on the whole. Integrating the hydropower station monitoring information into Geographic Information System(GIS) environment, managers and engineers can dynamically gain the deformation information of the slop by query the symbols. By this means, designers can improve the correctness of analysis, and make a strategic and proper decision. Since the system is beneficial to effectively manage the monitoring-data, equitably save the cost of design and safe construction, and decrease the workload of the engineers, it is a successful application to the combination of hydropower station monitoring information management and computer information system technology.At the same time, on the basis of the geological analysis and rock mass toppling deformation and failure mechanism analysis of Longtan engineering left bank slope, the synthetic space-time analysis and influence factors analysis on the surface monitoring data and deep rock mass monitoring data of A-zone on left bank slope are carried on. It shows that the main intrinsic factor that effects the deformation of Zone A is the argillite limestone interbedding toppling structure, and its main external factors are rain and slope excavation. What's more, Degree of Reinforcement Demand(DRD) has been used to evaluate the slop reinforce effect of Zone A on left bank according to the Engineering Geomechanics-mate-Synthetics(EGMS). The result shows that the slop has been effective reinforced, and it is more stable after reinforce.At last, on the basis of contrasting with several forecast models, a synthetic forecast GRAV model has been presented and used to forecast the deformation of zone A on left bank in generating electricity period. The result indicates that GRAV model has good forecast precision, strong stability, and practical valuable reliability.
Resumo:
A novel technique for high-power extracavity pulse compression with a nonlinear solid material is demonstrated. Before spectral broadening by self-phase modulation in the solid material, a short filament generated in argon is used as a spatial filter, which works for a uniform spectrum broadening over the spatial profile. Compensated by chirped mirrors, a 15-fs pulse is generated from a 32-fs input laser pulse. A total transmission larger than 80% after the solid material is achieved.
Resumo:
We investigate the characteristics of Gaussian beams reflected and transmitted from a uniaxial crystal slab with an arbitrary orientation of its optical axis. The formulas of the total electric and magnetic fields inside and outside the slab are derived by use of Maxwell's equations and by matching the boundary conditions at the interfaces. Numerical simulations are presented and the field values as well as the power densities are computed. Negative refractions are demonstrated when the beam is transmitted through a uniaxial crystal slab. Beam splitting of the reflected beam is observed and is explained by the resonant transmission for plane waves. Dependences of the lateral shift on the incident angle and beam width are discussed. Negative and positive lateral shifts are observed due to the spatial anisotropic properties.
Resumo:
The properties of plasmonic very small aperture lasers are shown: these integrate surface plasmon structures with very small aperture lasers. The transmission field can be confined to a spot of subwavelength width in the far field, and according to the finite difference time domain simulation results the focal length of the spot can be modulated using different ring periods. Scanning of the subwavelength gating in the far field has been realized numerically. Such a device can be used with a high-resolution far-field scanning optical microscope.
Resumo:
Light transmission through a single subwavelength slit surrounded by periodic grooves in layered films consisting of Au and dielectric material is analyzed by the finite difference time domain method in two dimensions. The results show that the transmission field can be enhanced by the corrugations on the output plane, which is a supplementary explanation for the extraordinary optical transmission.
Resumo:
An analysis of the enhancement of light transmission through a sub-wavelength aperture by oil- or solid-immersion is presented in this letter. An output power enhancement phenomenon related to the oil-immersion or solid-immersion mechanism is realized experimentally and reported for a very small aperture laser, which is an agreement with simulation analysis. This phenomenon could be useful for future optical data storage, microscopy and lithography.
Resumo:
High output power very-small-aperture laser has been created on 650 nm edge emitting laser diodes. The far-field output power is 0.4 mW at the 25 mA driving current, and the highest output power exceeds 1 mW. The special fabrication process is described and the failure mechanism leading to the short lifetime of the devices is discussed.