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Liu T.,Tsinghua University | Wang B.,Tsinghua University | Cui Y.,Tsinghua University | Zhang J.,Tsinghua University | Zhang J.,Army Officer Academy PLA
Sensors and Actuators, A: Physical | Year: 2012

In the horizontal directional drilling (HDD) system, MWD (measurement while drilling) magnetic surveying technology is widely used. However, this system suffers from the interferences to the geomagnetic field and the accumulated errors. To guide the drilling process in this situation, a method for measuring direction and position of the drilling bit by combining two magnetic fields is proposed. To realize this system, a utility algorithm is established. Simulation experiments were implemented to prove the feasibility of the method and the errors were analysed. © 2012 Elsevier B.V. Source


Chong L.,Army Officer Academy PLA | Xing Y.,State Key Laboratory of Pulsed Power Laser Technology | Luozheng Z.,Army Officer Academy PLA
Applied Mechanics and Materials | Year: 2012

The current process hiding and detection technologies are analyzed and the mechanism of cross-views discrepancy utilized by Strider GhostBuster are studied in detail and based on Hardware-assisted Virtual Machine (HVM) a new framework for process detection is proposed namely HCPD whose effectiveness and integrality are verified through experiments. © (2012) Trans Tech Publications Switzerland. Source


Yin C.,Key Laboratory of Polarization Imaging Detection Technology in AnHui Province | Yin C.,Army Officer Academy PLA | Wang F.,Key Laboratory of Polarization Imaging Detection Technology in AnHui Province | Wang F.,Army Officer Academy PLA | And 6 more authors.
Guangxue Jishu/Optical Technique | Year: 2015

Based on the analysis of the non-homogeneity and non-consistency of the system response, two-point and radiometric calibration method is used to calibrate the system according to the linear characteristic of the system. To measurement the accuracy of the system before and after the calibration by using polarization measurement device and the study of detection experiment is carried out. The results show that the method can effectively improve the accuracy of the system to analyze the polarization information and enrich the details of polarization images. ©, 2014, Editorial Board of Optical Technique. All right reserved. Source


Wu B.,Army Officer Academy PLA | Zheng J.,Army Officer Academy PLA | Tian Q.-T.,Army Officer Academy PLA | Zou Z.-Q.,Army Officer Academy PLA | And 2 more authors.
Friction | Year: 2014

The engraving process of a projectile rotating band is one of the most basic research aspects in interior ballistics, which has not been thoroughly understood thus far. An understanding of this process is of great importance from the viewpoints of optimal design, manufacturing, use, and maintenance of gun and projectile. In this paper, the interaction of copper and nylon rotating bands with a CrNiMo gun barrel during engraving was studied under quasi-static and dynamic loading conditions. The quasi-static engraving tests were performed on a CSS-88500 electronic universal testing machine (EUTM) and a special gas-gun-based test rig was designed for dynamic impact engraving of the rotating bands. The mechanical behaviors of copper and nylon were investigated under strain rates of 10−3 s−1 and 2 × 103 s−1 using an MTS 810 and a split Hopkinson pressure bar (SHPB), respectively. Morphologies of the worn surfaces and cross-sectional microstructures were observed with scanning electron microscope (SEM) and optical microscope (OM). It was found that large deformation and severe friction occur during engraving. The surface layer is condensed and correlated with a hardness gradient along the depth from the top worn surface. The structure of the rotating band and gun bore, band material, and loading rate have great effects on band engraving. The flow stress-strain of the copper strongly depends on the applied strain rate. It is suggested that strain rate and temperature play significant roles in the deformation mechanism of rotating bands. © 2014, The author(s). Source


Wu B.,Army Officer Academy PLA | Zheng J.,Army Officer Academy PLA | Qiu J.,Army Officer Academy PLA | Zou Z.-Q.,Army Officer Academy PLA | And 5 more authors.
Journal of Adhesion Science and Technology | Year: 2016

Alternative materials are being investigated as substitution of the traditional copper rotating band, in order to solve problems associated with their mechanical and physical properties. Meanwhile, new processes for joining the rotating band on the projectile body have also to be developed because of different material physical properties. In this paper, swaging, welding, and newly developed spraying technologies for fabricating rotating band are analyzed, respectively. Quasi-static and dynamic engraving methods are presented for evaluating the performance of as-prepared rotating band. The former was performed on an 810 Material Testing System and the latter was carried out by using a specially developed gas-gun-based impact test rig. Hoop and axial direction strain gauges were positioned on the exterior of the barrel to monitor the effect of the rotating band on the barrel during engraving process. It is suggested that aluminum bronze coating prepared by the High Velocity Arc Spraying (HVAS) process should be a good candidate for application to a rotating band of medium-and large-caliber projectiles. The measured strains were found to be dependent on a set of variables, such as loading rate, band material and structure, forcing cone and rifling (land and groove) structure, bore condition (oiled or dry), etc. The loading rate has been verified as the most important factor and the essential difference among quasi-static engraving, dynamic engraving, and actual firing. © 2016 Taylor and Francis. Source

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