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Li F.,Beihang University | Jiao Z.,Beihang University | Gui Y.,Beijing Monda Aviation Chemical | Lei W.,AVIC Beijing Keeven Aviation Instrument Co.
Beijing Hangkong Hangtian Daxue Xuebao/Journal of Beijing University of Aeronautics and Astronautics | Year: 2010

The arresting system stops the aircraft effectively when the aircraft passes beyond the end of the runway during an aborted takeoff or landing which minimizes the damage to the aircraft and the passengers. The arresting system is a kind of important safety facility for airports. Based on this, a new kind of soft ground arresting system was designed which has simple structure, high reliability, large maneuverability and outstanding generality. Combined with the aircraft 6-dof model and accurate resistance model, the soft ground arresting system mathematical model was built to analyze the process of arresting system. The system model was used to simulate the working process of the arresting system. Lots of important parameters, such as stopping distance and landing gear load were obtained. Compared with the experiments done in foreign countries, the simulation results were proved effective, which could be widely used in the construction and reconstruction of the airports.

Yuan R.,Beihang University | Song N.,Beihang University | Zhang G.,AVIC Beijing Keeven Aviation Instrument Company | Jin J.,Beihang University
IEEE Sensors Journal | Year: 2013

An algorithm for autonomously detecting angle random walk and quantization noise of fiber optic gyro in attitude determination system of satellite is proposed. To remove the information of satellite movement from gyro output, a star sensor can be used as an attitude standard, and the difference between angle increments of star sensor and gyro can be taken. The residual of the difference is analyzed using a simplified Allan variance method. As a byproduct of the difference, the noise of star sensor disturbs the variance analysis. This disturbance is reduced by a self-cancellation algorithm of star sensor noise. The simulation results show that the algorithm can detect 4.19exp-4°/ √h angle random walk and 4.39exp-6° quantization noise in real time, and reflect degenerations in angle random walk and quantization noise of gyro caused by gamma radiation in space. The algorithm meets the requirements of autonomous detection in space, and is beneficial to performance maintainability and reconfiguration of the attitude determination system in satellite without any ground support. © 2001-2012 IEEE.

Ren W.,Harbin Institute of Technology | Wei J.,Harbin Institute of Technology | Ma X.,AVIC Beijing Keeven Aviation Instrument Co. | Cui L.,G and A Technology Co.
Materials Research Innovations | Year: 2015

The typical characteristics of the change in contact resistance and tangential force with fretting cycles are compared with different fretting frequencies. Intermittent phenomena or short duration discontinuities during each fretting cycle are recorded explicitly. The instantaneous higher contact resistance values that appeared at the contact zones continuously corresponded to the distorted tangential force between contacts. Fretting frequency was determined as the crucial parameter that influenced the intermittent contact resistance. Subsequently, the contact failure mechanism of frictionally heated electrical contacts during high-frequency fretting was explained by introducing the electrical contact theory and thermoelastic instability model. © W. S. Maney & Son Ltd 2015.

Ren W.,Harbin Institute of Technology | Wang P.,Harbin Institute of Technology | Ma X.,AVIC Beijing Keeven Aviation Instrument Co. | Xue S.,Harbin Institute of Technology | And 2 more authors.
Diangong Jishu Xuebao/Transactions of China Electrotechnical Society | Year: 2013

Au-plated copper contact material is applied in aerospace electrical connectors widely, and the fretting wear characteristics between contacts induced by high frequency vibration is very important for the reliability of electrical connectors. The fretting wear testing system and relative analysis method based on electro-dynamic vibrator are presented. The contact resistance and tangential force and surface morphology of two contacts are analyzed by changing different amplitude during the whole fretting cycles. Therefore the fretting failure modes and fretting failure mechanism are determined explicitly. The conclusions drawn are meaningful for contact material optimization and contact pair optimal design.

Ren W.-B.,Harbin Institute of Technology | Wang P.,Harbin Institute of Technology | Ma X.-M.,AVIC Beijing Keeven Aviation Instrument Co | Xue S.-J.,Harbin Institute of Technology | And 2 more authors.
Mocaxue Xuebao/Tribology | Year: 2013

Metal contact plays a key role in conducting current and transmitting signals in electrical and electronics engineering fields. However, fretting caused by mechanical vibration stress degrades the electrical contact behavior gradually, and induces the intermittency phenomenon. This paper investigated the fretting behavior of Au-plated copper contacts and the variation of contact resistance was obtained by using an electro dynamic shaker. By analyzing contact resistance and worn surface morphology, the relationship between fretting frequency and amplitude inducing the intermittency phenomenon and the intermittency failure mechanism was discussed.

Rong J.-L.,Beijing Institute of Technology | Gan Z.-K.,Beijing Institute of Technology | Wang D.,AVIC Beijing Keeven Aviation Instrument Company Ltd | Cao M.-S.,Beijing Institute of Technology
Computational Materials Science | Year: 2015

A new method to generate a three-dimensional (3D) nanoscale tetrapod-shaped zinc oxide whisker (NT-ZnOw) with spatial random distribution is proposed, and a corresponding program is developed. A whisker-generating program is combined with finite element method to build a 3D finite element model that can predict the mechanical properties of NT-ZnOw/resin composites. A 3D finite-element unit cell is adopted and subjected to periodic displacement boundary conditions to explore the equivalent mechanical properties of the NT-ZnOw/resin composites. A micromechanics finite element model of the NT-ZnOw reinforced composites containing various volume fractions of NT-ZnOw is also developed. Effects of different volume fractions and aspect ratios of the whisker on the stiffness of the composites are investigated. These parameters can be used in the microscopic prediction and analysis to determine the mechanical properties of whisker-reinforced composites with multivariate and random distribution of the whiskers. The numerical and theoretical predictions are in good concordance. © 2014 The Authors. Published by Elsevier B.V.

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