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手征平板介质波导中的场分析 总被引:7,自引:0,他引:7
本文首次研究了手征平板介质波导中电磁波的传播特性,给出了波导中的场分布、色散关系和截止方程,以及最低截止波数Kc随手征导纳ζc的变化规律。结论表明,在手征平板介质波导中,TE、TM和TEM模均不能单独传输,其伸输模是耦合模。当ζc趋于零时,本文的所有结果均退化成通常平板介质波导情形。 相似文献
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Key areas of robot agility include methods that increase capability and flexibility of industrial robots and facilitate robot re-tasking. Manual guidance can achieve robot agility effectively, provided that a safe and smooth interaction is guaranteed when the user exerts an external force on the end effector. We approach this by designing an adaptive admittance law that can adjust its parameters to modify the robot compliance in critical areas of the workspace, such as near and on configuration singularities, joint limits, and workspace limits, for a smooth and safe operation. Experimental validation was done with two tests: a constraint activation test and a 3D shape tracing task. In the first one, we validate the proper response to constraints and in the second one, we compare the proposed approach with different admittance parameter tuning strategies using a drawing task where the user is asked to guide the robot to trace a 3D profile with an accuracy or speed directive and evaluate performance considering path length error and execution time as metrics, and a questionnaire for user perception. Results show that appropriate response to individual and simultaneous activation of the aforementioned constraints for a safe and intuitive manual guidance interaction is achieved and that the proposed parameter tuning strategy has better performance in terms of accuracy, execution time, and subjective evaluation of users. 相似文献
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电力系统仿真的准确度直接关系到系统的安全经济运行,其中负荷模型对仿真结果有显著的影响。大型电力系统仿真软件PSS/E所具有的高度模块化的结构,以及其模型库中所提供的丰富的设备模型,特别是其自带的二次开发语言IPLAN使得它能够完成各种各样的仿真任务。基于PSS/E,用接地时变导纳的动态等值方法对系统进行混合仿真,即注入实测数据代替某部分电网,发现采用不同的负荷模型对混合仿真误差有很大的影响,最后分析了原因。 相似文献
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基于回传射线矩阵法,得到均质土中部分埋入粘弹性桩在单位脉冲作用下的桩顶速度导纳,然后利用Fourier逆变换和卷积定理得到了在瞬态半正弦激振力作用下的桩顶速度时域响应,与全埋入粘弹性桩作对比,分析桩身材料阻尼、外露桩长、桩侧土阻尼和刚度及桩底土阻尼和刚度对桩顶速度导纳和反射波的影响.结果表明:桩材料阻尼、外露桩长、桩侧土阻尼和桩底土阻尼对桩顶频域及时域速度响应有显著影响;桩侧土刚度和桩底土刚度只对速度导纳曲线的低频部分有影响,且桩底土刚度对导纳曲线的相位和反射波的形状及幅值有显著的影响. 相似文献
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This paper demonstrates a haptic device for interaction with a virtual environment. The force control is added by visual feedback
that makes the system more responsive and accurate. There are two popular control methods widely used in haptic controller
design. First, is impedance control when user motion input is measured, and then, the reaction force is fed back to the operator.
The alternative method is admittance control, when forces exerted by user are measured and motion is fed back to the user.
Both, impedance and admittance control are also basic ways for interacting with a virtual environment. In this paper, several
experiments were performed to evaluate the suitability of force-impedance control for haptic interface development. The difference
between conventional application of impedance control in robot motion control and its application in haptic interface development
is investigated. Open loop impedance control methodology is implemented for static case and a general-purpose robot under
open loop impedance control was developed as a haptic device, while a closed loop model based impedance control was used for
haptic controller design in both static and dynamic case. The factors that could affect to the performance of a haptic interface
are also investigated experimentally using parametric studies. Experimental results for 1 DOF rotational motion and 2 DOF
planar translational motion systems are presented. The results show that the impedance control aided by visual feedback broaden
the applicability of the haptic device and makes the system more responsive and accurate.
相似文献
J. SasiadekEmail: |
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正确认知射频导纳液位计 总被引:1,自引:0,他引:1
以DREXELBROOK公司的射频导纳液位计为例,从概念、结构、原理和应用几方面对射频导纳液位计进行了一系列剖析,以便使人们了解射频导纳液位计的本质,消除一些错误认识,从而更好地发挥其作用。 相似文献