Papers by Author: Xi Lin Zhu

Abstract: In the design process of gauge visual detection system between high signals and contact net, it is need to do target positioning and segmentation between high signals and contact line. The paper first analyzes the structural characteristics of high signals and contact line, and then uses the Sobel operator for edge detection, and uses first close and then open of image morphological operations for edge treatment, finally uses Hough transform for line and circle detection to extract the object's edge. This positioning and segmentation of target object would be achieved.

Abstract: By researching on the main factors affecting the active zone area strain of electroactive dielectric elastomers, the suitable conditions of area strain for the material in the application as artificial muscles actuator was determined. In the experiments, the strain characteristics of the material was investigated under uniaxial pre-stretching, uniform biaxial pre-stretching and non-uniform biaxial pre-stretching respectively. In addition, the strain rates of the materials active zone under different ratio of the active zone to the window radius of the materials were investigated. The experimental results show that the area strain of active zone would have inflexion under any pre-stretching condition, and the area strain increased with applied voltage increasing, decreased with the ratio of the active zone to the window radius increasing. It could be found that the strain conditions have an important influence on the area strain of the active zone.

Abstract: Prestrain affects the performance of dielectric elastomer actuators so much that rare actuators is used before pre-stretching. In this article, the author made a series of circular actuators with acrylic VHB4910 and graphite mixture electrodes, and performed contrast experiments, under non-prestrain, uniaxial prestrain and equibiaxial prestrain, respectively, to figure out the changing of area strain against prestrain. Result of experiment indicates that the film actuator obtains the highest output strain while applying equibiaxial prestrain. An optimum prestrain ratio of actuators, in this research, occurs between 150%~200% under equibiaxial prestrain condition. This result has practical value in the future design and use of dielectric elastomer actuators.

Abstract: The architecture and operation theory of Giant Magnetostrictive Accurate-motion Actuator have been introduced. After analysing the driving characteristic of giant magnetostrictive material and requirement of driving power, a design method of wide range and high precision NC constant-current source has been put out. The output circuit is composed of serial 12-bit DACs Max531, low-noise high-speed precision operational amplifiers OP27 and driving circuit. It provides current from 0 to 2.048A with 0.5mA step value. Two fully differential input channels 16-bit, sigma-delta ADCs AD7705 collects output current in feedback loop. Current ripple is controlled under 0.25mA through using homemade high-performance linear power. The result shows that the driving power with characteristic of high stability and fast response meets the needs of driving of Giant Magnetostrictive Accurate-motion.

Abstract: According to the processed materials, characteristics of their shapes, process precision and other conditions, a fuzzy neural network (FNN) can be trained with experiment data. The trained network can automatically select process parameters by using the fuzzy neural network (FNN) technology, and the selected process parameters can be saved in the computer in file. In this way, the selected process parameters can enter into the process program during the programming and the automatic selection can be accomplished, so that full automatic achievement of NC process program is feasible.

Abstract: The transient characteristic of single-sided linear induction motor (LIM) was simulated and computed using the electromagnetic field finite element analysis software Ansoft. The change of the thrust, the primary current and the air-gap’s magnetic field of linear induction motor was analyzed under the different air-gap’s size condition. The analysis result shows that, with the growth of air gap, the motor thrust reduces but the primary current increases, and the distribution of motor air-gap magnetic field is uneven due to the existence of end effects. Finally a comparison is made between the simulation result and the experiment result, which indicates the correctness of simulated model, thus it can provide important basis for the manufacture, optimized design and control of LIM which is used in subways.

Abstract: Based on the theory of Wavelet decomposing algorithm, in this paper an algorithm of redundancy real-time denoising is presented, and the test of on-line identification mode of a hydraulic cylinder’s work load pressure signals was fulfilled. This method can improve the stability of the signal collection and the control accuracy of hydraulic cylinder pressure effectively, solve the crawling phenomenon of hydraulic cylinder when working, and reduce the signal collection error resulted from the load mutation. By means of controlling the wavelet decomposing depth, the calculation amount of real-time denoising is controled, thus the optimization of the signal, damping vibration and denoising are achieved.

Abstract: In this paper, a system was introduced, which bases on Flame Cutter NC System and software platform of LabVIEW which the USA NI company developed. Composing of NC machine, partition of modules and assignments, functions confirming, data processing of machining and control, structure of software by the numbers and realization method of two CPUs. The system makes use of multitasking of LabVIEW to make the programmer realize easily the task, which is difficulty to acquire in in tradition programme. It is a kind of comparatively convenient and swift thinking to realize system interface and multitasking by the platform of LabVIEW.