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Design of a miniature axial flux flywheel motor with PCB winding for nanosatellites (EI CONFERENCE) 会议论文
2012 International Conference on Optoelectronics and Microelectronics, ICOM 2012, August 23, 2012 - August 25, 2012, Changchun, China
Wu J.
收藏  |  浏览/下载:34/0  |  提交时间:2013/03/25
This paper presents the design and analysis of an axial flux permanent-magnet (AFPM) machine for nanosatellites application. It is a miniature axial flux surface mounted permanent magnet flywheel motor  using a printed circuit board (PCB) stator winding. The PCB stator has simplified the design and construction and avoids unnecessary space  since size reduction has become one of the most important aspects of flywheel motor design for nanosatellites. The performances of the machine are estimated by combination method of three-dimensional (3D) electromagnetic finite element analysis (FEA) and approximate theoretical analysis. The back EMF and electromagnetic torque are derived. A comparison between the analysis and experimental measurement results of the prototype machine is also presented. Both simulated and experimental results show that the proposed motor would be an acceptable solution for the nanosatellite applications with advantages such as simple structure and low-cost  as multi-layer circuit board production techniques have made the production of printed circuit coils cheaper and easier. 2012 IEEE.  
An appraisal method of dynamic interpolation error for high precision encoder (EI CONFERENCE) 会议论文
2011 International Conference on Electronics and Optoelectronics, ICEOE 2011, July 29, 2011 - July 31, 2011, Dalian, China
Yi J.; An L.-M.; Liu C.-X.; Wan Q.-H.
收藏  |  浏览/下载:11/0  |  提交时间:2013/03/25
The research of the accurate measure of static transfer function for the TDI CCD camera (EI CONFERENCE) 会议论文
3rd International Photonics and OptoElectronics Meetings, POEM 2010, November 2, 2010 - November 5, 2010, Wuhan, China
Guo-Ning L.; Long-Xu J.; Jian-Yue R.; Wen-Hua W.; Shuang-Li H.
收藏  |  浏览/下载:18/0  |  提交时间:2013/03/25
In the test course of static transfer function of TDI CCD camera  because of the influence that gets environmental and artificial etc. factor  the value of static transfer function measured at any time is between unceasing fluctuation  so  make accuracy reduce. To solve this problem  a kind of accurate measurement technique of static transfer function is put forward. First  before carrying out the measure of static quiet of transfer function  the best test point of transfer function of the TDI CCD camera must be determined  it is parallel to guarantee the rectangle target surface of parallel optical pipe and camera focal plane maintenance parallel  and again guarantee target strip in rectangle target and TDI CCD in camera focal plane maintenance vertical. TDI CCD catches rectangle target image  per 1000 lines of target mark image as a measures sample of static transfer function  exclude because of atmosphere tremble twisted  vague rectangle target mark image  retain 500 distinct and steady target mark image as measure sample set. Then  calculate the static transfer function of each measure sample respectively  take the average of all static quiet transfer function in measure sample set as the static transfer function of camera. Finally  the measure of the static transfer function for TDI CCD camera makes error analysis. Experimental results indicate that the value of the static transfer function of TDI CCD camera measured with this kind of method is 0.2923  with before measurement technique comparison  the value of static transfer function has raised 0.02  makes the accuracy of the measure of static transfer function have gotten raising.  
Roughness analysis of optical surfaces by X-ray scattering (EI CONFERENCE) 会议论文
2011 International Conference on Electronics and Optoelectronics, ICEOE 2011, July 29, 2011 - July 31, 2011, Dalian, China
Meng Y.; Chen B.; Chen C.
收藏  |  浏览/下载:18/0  |  提交时间:2013/03/25
A grazing incidence x-ray scattering (XRS) method  Order perturbation theory (FOPT)  is stated briefly and an experimental facility based on an improved X-ray diffraction has been introduced  which can work with high performance. The x-ray scattering distributions of two super smooth silicon samples measured at the incidence angle 0.2 degree  as the x-ray wavelength is 0.154 nm  have been given and analyzed by the FOPT to give information about the surface profiles. As a comparison  the root mean square (RMS) surface roughness  grey-scale maps and one-dimensional power spectral density (1D PSD) have been derived from the atomic-force microscope (AFM) data. The results evaluated by FOPT are in good agreement with that of AFM  which indicates that x-ray scattering method is a practical characterization for the investigation of super smooth surfaces. 2011 IEEE.  
Experiments of second harmonic generation output in pulsed TEA CO 2 laser (EI CONFERENCE) 会议论文
High-Power Lasers and Applications V, October 18, 2010 - October 19, 2010, Beijing, China
Guo R.; Li D.
收藏  |  浏览/下载:42/0  |  提交时间:2013/03/25
It is always the hot subject to realize the output of high-power laser in the range of 3-5m wavelength. This rang of wave band has greatly important applications in military because it located in the atmosphere window. Generally there are two ways to obtain this range of laser wavelength. One way is through optical parameter oscillation (OPO) from shorter laser wavelength and the other is through second harmonic generation (SHG) from longer laser wavelength. Firstly  the comparison between tow nonlinear crystals ZnGeP2 and AgGaSe2 is conducted for their nonlinear coefficient and damaging threshold in theory. The theoretical results show that the crystal AgGaSe 2 is more suitable for the SHG of pulsed TEA CO2 laser. When using pulsed TEA CO2 laser with wavelength of 9.3m to pumping AgGaSe2 SHG crystal  the wavelength of 4.65m is obtained. In the condition of repetition rate 100Hz  the upmost output power of single pulse is up to level of 1W  which corresponding efficiency of SHG is about 6%. The experimental results show that the polarization of laser beam has greatly influence on the SHG output of the crystal. Under the radiation of 3MW/cm 2 from fundamental wave and the right position for maximal SHG output in the crystal  when polarization of laser beam rotates 4.5  the SHG output of energy decrease about 30%. The research of this paper will make a foundation for further development of mid-infrared laser. 2010 Copyright SPIE - The International Society for Optical Engineering.  
Research on the close noise field of the piezoelectric pump (EI CONFERENCE) 会议论文
2006 IEEE International Conference on Mechatronics and Automation, ICMA 2006, June 25, 2006 - June 28, 2006, Luoyang, China
Jizhuang L.; Jianhui Z.; Shouyin W.; Qixiao X.; Desheng L.
收藏  |  浏览/下载:42/0  |  提交时间:2013/03/25
Restraining the noise  meanwhile  improving the dynamic characteristics of the driving power of piezoelectric pump effectively are the final purposes of doing research on the reciprocating and flexural vibration of the piezoelectric vibrator. However  among many papers regarding piezoelectric pump  there are very few papers about the research on the noise of piezoelectric pump. This is far less than the research on the application of the piezoelectric pump in other fields. In this paper  the research on the flexural vibration deformation and vibration radiation noise of the piezoelectric vibrator are carried out. Firstly  the vibration equations of the piezoelectric vibrator are built and flexural vibration deformation function is deduced. Then  the simplified vibration model of the piezoelectric vibrator is introduced by using vibration theories of micro-area piston. Furthermore  theoretical calculation equations of sound pressure in close noise field and noise contribution equation of fluid in pump are deduced. Finally  a comparison is made between the theoretical calculation value and experimental value  and the contribution quantities of the piezoelectric vibrator and fluid in pump are obtained respectively under different frequencies. The consequence approves that the theory introduced by this research is true. 2006 IEEE.  


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