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Li K.,Joint Laboratory of Flight Vehicle Ocean Based Measurement and Control | Lin X.-L.,Joint Laboratory of Flight Vehicle Ocean Based Measurement and Control | Hu X.-J.,Joint Laboratory of Flight Vehicle Ocean Based Measurement and Control | Cai Z.-G.,Xi'an Jiaotong University
Journal of Donghua University (English Edition) | Year: 2015

To overcome the problem that a single feature can not reflect the state of machinery in different stages, a method of vibration feature fusion based on self-organizing map (SOM) is presented. Minimum quantization error (MQE) is obtained unsupervised based on SOM network. And trend information of the MQE curve is extracted by the wavelet packet to enhance state differentiating. Experimental flat is designed for bearing accelerating fatigue. And experimental results show that the method of vibration feature fusion based on SOM can reflect the state of machinery in different stages effectively. Copyright © 2015 Editorial Department of Journal of Donghua University. All rights reserved.


Zhu W.K.,Joint Laboratory of Flight Vehicle Ocean based Measurement and Control | Li H.F.,Joint Laboratory of Flight Vehicle Ocean based Measurement and Control | Mu J.S.,Joint Laboratory of Flight Vehicle Ocean based Measurement and Control | Xue G.H.,Joint Laboratory of Flight Vehicle Ocean based Measurement and Control | Dai Z.X.,Joint Laboratory of Flight Vehicle Ocean based Measurement and Control
Applied Mechanics and Materials | Year: 2013

Tracking data containing outliers would seriously distort the accuracy of data processing for space tracking ships. Effective measures have to be adopted for the detection and correction of outliers. The time series of observations obtained by space tracking ships contain complex periodical elements caused by ship deformation and rolling. It brings difficulty to the detection of outliers. To solve the problem, a variety of detection methods were studied based on measurement elements representation model. The paper gives an analysis about the characteristic of measurements taken by the ships and proposes to detect the information about outliers by considering the correlation in time, space and data properties. A detection model based on spline function representation model is constructed and tested. Numerical results show that the proposed method can detect and correct outliers effectively, and provide an alternative to the current method of the measurements processing for the space tracking ships. © (2013) Trans Tech Publications, Switzerland.


Qu Y.,Joint Laboratory of Flight Vehicle Ocean Based Measurement and Control | Cong B.,Joint Laboratory of Flight Vehicle Ocean Based Measurement and Control
Proceedings of the International Astronautical Congress, IAC | Year: 2013

Ship rolling affects greatly the stable tracking of the space tracking ship's instrumentation radar, especially of the unified X-band system, whose beam is very narrow and object acquisition and stable tracking becomes much more difficult in dynamic environment of the sea. This paper proposes and elaborates various techniques to overcome this challenge and to get quick acquisition, improve isolation of ship rolling, reduce dynamic lag, and enable the shipboard narrow-beam system to track stably with required accuracy. Copyright© (2013) by the International Astronautical Federation.


Cong B.,Joint Laboratory of Flight Vehicle Ocean Based Measurement and Control | Xi Z.,Joint Laboratory of Flight Vehicle Ocean Based Measurement and Control | Wang J.,Joint Laboratory of Flight Vehicle Ocean Based Measurement and Control | Wu Y.,Joint Laboratory of Flight Vehicle Ocean Based Measurement and Control
Proceedings of the International Astronautical Congress, IAC | Year: 2013

Space tracking ship is still playing an important role in Chinese TT&C (Telemetry, Tracking and Command) network. To meet the needs of future space programs, the new-generation space tracking ships were built, which adopted many new and advanced techniques. This paper introduces the TT&C system and ship attitude and positioning system of the new-generation space tracking ships. Limited room, adversary environment and ship rolling are the main challenges which must be overcome and thus the design is much different from those of land- based stations. The concept of integration and reuse prevails in the whole system and is elaborated in this paper. The error of ship positioning and attitude contributes greatly to the final result, so various techniques are exploited to improve the accuracy. Future research directions are also addressed and possible approaches for future challenges are discussed. Copyright© (2013) by the International Astronautical Federation.


Li H.F.,Joint Laboratory of Flight Vehicle Ocean based Measurement and Control | He J.W.,Joint Laboratory of Flight Vehicle Ocean based Measurement and Control | Li H.Y.,Joint Laboratory of Flight Vehicle Ocean based Measurement and Control | Dai Z.X.,Joint Laboratory of Flight Vehicle Ocean based Measurement and Control | Ji Q.,Joint Laboratory of Flight Vehicle Ocean based Measurement and Control
Advanced Materials Research | Year: 2014

Releasing beacon balloons is an effective way for space TT&C ship to obtain accurate comparison data and an important resource for accuracy evaluation. However, it is hard for theodolite to keep track beacon balloon stably for a long time. Its function has not been realized because the time period of the effective data is so short that it can not satisfy the request of traditional accuracy evaluation test. Aiming at this problem, this paper suggests an assumption of accuracy evaluation based on dynamic time interval non-continuous variable data. Utilizing self–adaptive outlier detection method and fitting residual error method, this paper solves the puzzle of dealing with dynamic time interval data which can not be treated by existing method, and realizes the self-determination of space TT&C ship accuracy evaluation test. © (2014) Trans Tech Publications, Switzerland.


Pan L.,Joint Laboratory of Flight Vehicle Ocean Based Measurement and Control | Zhou H.-Y.,Joint Laboratory of Flight Vehicle Ocean Based Measurement and Control | Zhang T.-S.,Joint Laboratory of Flight Vehicle Ocean Based Measurement and Control | Zhao L.-J.,Joint Laboratory of Flight Vehicle Ocean Based Measurement and Control
Zhongguo Guanxing Jishu Xuebao/Journal of Chinese Inertial Technology | Year: 2015

The poor rolling precision of single star sensor has harmful affect on the heading measurement accuracy. The accuracy of ship attitude can be improved by using dual star sensors, in which the key methods are refraction correction and combined attitude determination. At present, the refraction correction method is usually based on the star observation vector correction, and the combined attitude determination method is based on dual optical axis combination. These two methods need introducing the initial ship attitude in refraction correction, and the iterative correction solution process is complex. In addition, the single star sensor needs at least 4 stars to be identified before the ship attitude can be calculated. In view of these problems, a new method for determining the ship attitude by dual star sensors is proposed, which includes the refraction correction based on the star theoretical vector correction and the combined attitude determination method base on the star observation vector combination. The refraction correction by the new method no longer need the initial ship attitude, and in theory the ship attitude can be obtained only if each of the dual star sensors can identify at least 1 star. Experiment results show that the ability of dual star sensors to obtain the ship attitude is improved by the proposed method. ©, 2015, Editorial Department of Journal of Chinese Inertial Technology. All right reserved.


Li H.F.,Joint Laboratory of Flight Vehicle Ocean based Measurement and Control | Zhu W.K.,Joint Laboratory of Flight Vehicle Ocean based Measurement and Control | Xue G.H.,Joint Laboratory of Flight Vehicle Ocean based Measurement and Control | Xu X.C.,Joint Laboratory of Flight Vehicle Ocean based Measurement and Control | Di L.P.,Joint Laboratory of Flight Vehicle Ocean based Measurement and Control
Advanced Materials Research | Year: 2014

To meet the demand of ship-board TT&C equipment' measurement precision, it's necessary to calibrate the equipment to define the error parameters. And the error parameters should be suitable for the revising model. Based on the research of instrumentation ship's calibration technology and angle error revising theory of the ship-board TT$C equipment, this article found the error of the revising model of the ship-board TT&C equipment and bring forward the updated model how to revise the angle error by calibration for zero method, which solved the problem that azimuth error aperiodically arises. © (2014) Trans Tech Publications, Switzerland.


Mao Y.-X.,Chinese Academy of Sciences | Mao Y.-X.,Joint Laboratory of Flight Vehicle Ocean based Measurement and Control | Ma J.-Y.,Chinese Academy of Sciences | Zhang J.,Chinese Academy of Sciences | Song Y.-Z.,Chinese Academy of Sciences
Yuhang Xuebao/Journal of Astronautics | Year: 2014

In a satellite launch task using spring separation mode, the satellite obtains a velocity increment produced from the separating force of spring, data of two segments before and after the epoch of satellite-rocket separation are not in the same orbit, and can't be used to calculate the orbit together by using traditional method. To solve the problem, a new method, improved method of perturbed initial orbit determination based on Unit Vector Method, is proposed to solve a position vector and two velocity vectors simultaneously in this paper. The results of simulated and measured data show that the method can realize combined orbit determination by using the measured data of two different orbits before and after the satellite-rocket separation. Because the orbit determination data is increased, the accuracy of initial orbit determination in injection phase is also improved. ©, 2014, China Spaceflight Society. All right reserved.


Li H.F.,Joint Laboratory of Flight Vehicle Ocean based Measurement and Control | Xue G.H.,Joint Laboratory of Flight Vehicle Ocean based Measurement and Control | Mu J.S.,Joint Laboratory of Flight Vehicle Ocean based Measurement and Control | Xu X.C.,Joint Laboratory of Flight Vehicle Ocean based Measurement and Control | Hao S.,Joint Laboratory of Flight Vehicle Ocean based Measurement and Control
Applied Mechanics and Materials | Year: 2014

As China's space-tracking ships' missions change, there is ever higher demand on ships' orbit determination accuracy. This is reflected in Shenzhou missions, during which ships' orbit determination accuracy influences the whole tracking and control system. This paper bases its research on the analysis of error sources' influence on the determination of near-earth and near-round orbit, and proposes urgent problems and research prospects of maritime orbit determination accuracy enhancement. It establishes a model for adjusting ship attitude and speed, designs a self-adjusting information retrieval calibration method, realizes accurate simulation of ship complex error and researches on optimal selection of first-orbit root number based on sequence statistics. It also conducts research on improving preliminary treatment model and enhancing orbit report accuracy. © (2014) Trans Tech Publications, Switzerland.


Li H.F.,Joint Laboratory of Flight Vehicle Ocean based Measurement and Control | Zhu W.K.,Joint Laboratory of Flight Vehicle Ocean based Measurement and Control | Xue G.H.,Joint Laboratory of Flight Vehicle Ocean based Measurement and Control | Chen H.Y.,Joint Laboratory of Flight Vehicle Ocean based Measurement and Control | Di L.P.,Joint Laboratory of Flight Vehicle Ocean based Measurement and Control
Applied Mechanics and Materials | Year: 2013

This paper works on the general design of tracking ship's system software structure with an eye to the complexity of information source of maritime tracking, and illustrates the design technique, methods and application examples in its realization. In this paper, a separation of system software function from specific data format is proposed to adapt to the difference in data structure resulting from each tracking ship's unique equipment position and parameters. The difference in data structure is represented by parameters. The format information passed by parameter files is recorded by equipment sequence structure. A parameter program configuration is utilized and through real-time tracking data the allocation of system software is finished. The system can automatically adapt to data of different structure and treat all formats without rectifying software. The application software system designed in this conception has been used till today without major adjustments in its main structure. All changes can be adjusted via data files and in this way realizes adaptive processing. © (2013) Trans Tech Publications, Switzerland.

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