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Compared with traditional ceramic and glass insulators, aging phenomena of composite insulators is much more serious. High temperature, high humidity and heavy sea fog in coastal area pose great challenge to the operation of composite insulators. However, the effect of relatively complicated surrounding on composite insulator ageing is not clear yet. In this paper, a multi-factor aging system simulating...
In this paper, a humanoid grinding robot with two 6-DOF manipulators is proposed. The robot is equipped with force/torque sensors and binocular vision cameras, through which the interaction between the robot and the environment can be recognized and serves as a feedback for adaptive grinding control. Kinematics of the dual-arm robot is analyzed. Simulation of a grinding movement is carried out in...
This paper proposes a novel method which uses online measurement data to create robot path for 3D grinding of workpieces with complex surfaces. The surface is measured as point cloud by a 3D scanner. The point cloud data is processed by filtering and smoothing, and then used for path planning. The grinding paths are generated by creating a series of planes to intersect with the target surface. A point...
W/Cu composites have received much attention for applications as in electronic packaging and heat sink materials. There exists difficulties in fabricating W/Cu composites due to the mutual insolubility of tungsten and copper. In this article, high density 1 wt. %Ag-W/Cu composites are prepared by sintering the mixed powders of copper-coated tungsten powders and silver-coated copper powders under different...
Optical tweezers have become an efficient tool to trap microscopic and nanoscopic objects and manipulate their mechanical motion via optical forces and torques [1–3]. In this talk we discuss our recent experimental and theoretical works on trapping and manipulation of micrometer-size Janus particle with half surface of polystyrene particle coated with nanometer-thick gold thin film in various optical...
Plasmonic nanostructures can help to greatly enhance light-matter interaction that in involved in many energy transfer and transformation processes [1, 2]. Here we discuss design and fabrication of symmetry-broken plasmonic spiral conical tips that enable efficient transport and focusing of optical signal and energy input from optical fiber via surface plasmon polariton (SPP) [3, 4]. Metallic probes...
This paper presents the developments of finger joints imitating human's joint with soft material to get the adaptability about unstructured environment and unexpected impacts. Lots of researches about robot hand have showed the methods that robot can co-work with humans using high level control algorithm or soft materials, but there are limitation. To get the adaptability and robustness, it is necessary...
Zero-index metamaterials (ZIMs) in which permittivity (ε) and/or permeability (μ) are zero possess unprecedented abilities to manipulate the electromagnetic (EM) waves. The applications of ZIMs include EM energy control in a very narrow waveguide, wave front control, cloaking and transmission control by defects, etc.. For isotropic (anisotropic) ZIMs, both components (only one component) of the ε...
We discuss our recent experimental and theoretical works on the efficient generation of prominent and robust Fano resonances in 3D metamaterials (MMs). The 3D MMs are formed by integrating vertical U-shape SRRs or vertical rectangular plates along a planar metallic hole array with extraordinary optical transmission (EOT) built by means of homemade focused ion-beam (FIB) lithography [1, 2]. In such...
Efficient coupling of light to single subwavelength structures is an important theme of many optical researches [1]. The extent to which a nanoscale object and the mode of an optical cavity are strongly coupled is determined by both cavity finesse and mode volume. In this context, a silica fiber tapered down to a few microns or smaller and then sandwiched between two integrated mirrors exhibits attractive...
This paper proposed a new transient stability assessment (TSA) method based on the power angle space reduction on the trajectory phase plane (TPP). Firstly, the dimension of the power angle trajectory was reduced in power-angle space. Secondly, the trajectory was projected in a one-dimensional coordinate axis in order to present its physical significance. Thirdly, a new phase plane was formed according...
This paper presents a machine-learning approach for regional photovoltaic (PV) power forecasting of up to 2 days ahead with hourly resolution. Physical PV power model is aggregated by geographical clusters and then summed for an entire ISO load zone. Numerical weather prediction (NWP) forecasts provide parameters, such as irradiance, temperature, barometric pressure, and wind speed, which are used...
The bubble mechanism based on field emission has long been considered to be responsible for breakdown in liquids under impulses with durations of microseconds. Hence, it is quite reasonable to associate the insulation failure with electrode materials. In this paper, the 50% impulse breakdown voltages and the discharge time delay with different metal electrode materials were acquired through experiments,...
The aim of this study was to clarify the hydrostatic pressure effect on the initiation and propagation process of oil streamers under the application of pulsed voltage with different polarities. The statistical characteristics of the impulse breakdown voltage and time lag in transformer oil were studied over a wide range of hydrostatic pressure, and the statistical discharge time lag and the discharge...
Rogers Ratio Method (RRM), Duval Triangle Method (DTM), IEC Ratio Method (IRM) (Basic Gas Ratios Method) and GB/T 7252 (National Standard of the People's Republic of China) are popular conventional methods for interpreting the possible faults indicator of transformer. Each of them has its own characteristics and these methods may have different interpreting results for the same data. This research...
An adaptive autonomous navigation method for medium earth orbit (MEO) and high earth orbit (HEO) satellites is proposed by using four constellation systems to overcome shortcomings of low visibility, liability and usability of single mode or dual-mode positioning systems. Firstly, based on the analysis of the visibility and compatibility of constellation satellites, satellites selection is realized...
An automatic disturbance rejection control (ADRC)-based model predictive torque control (MPTC) strategy is developed for permanent magnet synchronous motors (PMSMs) fed by three-phase four-switch inverters. The model of a PMSM fed by a three-phase four-switch inverter is built firstly. Then the ADRC and MPTC are respectively designed. The resultant ADRC-based MPTC PMSM fed by an unhealthy inverter...
The attitude control algorithm and guidance law for exoatmospheric kill vehicle (EKV) intercepting tactical ballistic missile (TBM) are investigated. Firstly, the six degree-of-freedom motion model of EKV and the model of divert and attitude control system (DACS) are presented. Next, for the purpose of tracking the target, the time-scale separation theory is applied to design the attitude controller...
Autonomous mobile robots need to acquire environment information for localization and navigation, and thus are usually equipped with various sensors. Consequently, the system is complex and expensive, bringing obstacles for general home applications. In this paper, we present an efficient, yet economic and simple solution for indoor autonomous robots, consisting of a basic mobile platform, a Kinect...
As soft computing techniques are more and more widely used in machining process, Artificial Neural Network (ANN) has become an effective way to construct predicting model in grinding process. The present paper reviews the efforts made in recent two decades on modeling grinding process via ANN in a sequence as input and output parameters, ANN topology and the details of the ANN training algorithm....
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