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A Review of Diagnostic Methods for Yaw Errors in Horizontal Axis Wind Turbines 期刊论文  OAI收割
ENERGIES, 2025, 卷号: 18, 期号: 3, 页码: 17
作者:  
Li, Qian;  Chen DY(陈丹阳);  Lin, Hangbing;  Yang XL(杨晓雷)
  |  收藏  |  浏览/下载:6/0  |  提交时间:2025/03/21
Gimbal displacement error analysis on an electro-optical seeker (EI CONFERENCE) 会议论文  OAI收割
Optical Design and Testing IV, October 18, 2010 - October 20, 2010, Beijing, China
作者:  
Zhang X.;  Zhang X.;  Zhang X.
收藏  |  浏览/下载:32/0  |  提交时间:2013/03/25
It is essential to analyze the gimbal displacement errors for a seeker due to the importance for cueing of targets and tracking for the final approach. Otherwise  for a seeker electro-driven with a concentric glass dome  the large errors will decrease the picking  pointing  and tracking precision rooted from the displacement errors existing between the rotation center of the optical system and the gimbal. And the gimbaled camera system displacement errors are never eliminated but reduced due to the geometric errors consists of geometric tolerances of gimbal structure  manufacture  installation and vibration coming from working environment. In this paper  the gimbal displacement errors in an electro-optically stabilized platform resulting from geometric errors and environment errors were analyzed and shown in detail. The mathematical modal of the gimbal displacement errors created based on multi-body dynamics demonstrated the connection between the gimbal displacement errors and the stabilized platform. Taking a visible light image seeker as a case  the diameter is 120mm  and the geometric tolerances came from the values of primary design and the vibration data came from the environmental vibration test on the pitch-yaw seeker  and at the same time  the errors resulting from installation were considered too. Based on calculating  the maximum gimbal displacement error will reach to 0.2mm for pitching angle smaller than 40 and yawing angle smaller than 60. However  the critical parts have been found out according to the probability theory and the reliability analysis successfully used in the paper  and finally  the maximum gimbal displacement error reduced to 0.1mm  which is acceptable corresponding to the picking  pointing and tracking precision for an optical imaging seeker. 2010 Copyright SPIE - The International Society for Optical Engineering.  
The method on the measurement of the aircraft attitude by the spatial cosines relationship of the single station and planes to the intersection the multi-station of electro-optical theodolite (EI CONFERENCE) 会议论文  OAI收割
2010 International Conference on Computer, Mechatronics, Control and Electronic Engineering, CMCE 2010, August 24, 2010 - August 26, 2010, Changchun, China
Zhao L.-R.; Cao Y.-G.
收藏  |  浏览/下载:16/0  |  提交时间:2013/03/25
In order to realize the aircraft attitude measurement  The paper advances electro-optical theodolite methods of measuring the aircraft attitude by using the spatial cosines relationship the single station theodolite and how to use intersection of the multi-station theodolite. The single station theodolite was introduced in a measured distance from the aircraft posture information. An exhaustive approach was used to access to the aircraft axis of the feature points and the location in the space was used to obtain space posture parameters. The multi-station theodolite was introduced to get the information of the aircraft flight attitude by method of using planes to the intersection. Two-dimensional image to obtain objective axis by fitting algorithm using Hough transform. And then  Calculate the vertical distance of the origin to the target of the central axis and the origin to the target of the central axis of the angle between the normal and the X-axis obtaining the linear equation in the two-dimensional plane. Two-dimensional axis of the target image and the camera system's optical center only identified a space plane. The aircraft yaw axis angle and pitch angle can be obtained by getting the space axis using plains to the intersection method. Experimental results show that attitude angle error of the single station theodolite is less than 1 when its distance is less than 6000m and attitude angle error of the multi-station theodolite is less than 0.6 when its intersection angle is between 30 and 150. In this paper  according to test result of precision comparing the mathematical model is correct and the algorithm is reasonable in extracting effective parameters of the aircraft's attitude. 2010 IEEE.  
Three-dimensional angle measurement based on auto-collimation and moire fringe (EI CONFERENCE) 会议论文  OAI收割
2008 International Conference on Optical Instruments and Technology: Optoelectronic Measurement Technology and Applications, November 16, 2008 - November 19, 2008, Beijing, China
Cai S.; Liang S.; Qiao Y.-F.
收藏  |  浏览/下载:28/0  |  提交时间:2013/03/25
A method for small three-dimensional (3D) angle measurement based on auto-collimation and moire fringe is proposed and analyzed. A right-angle prism is used as the indicator of angle change. The inclined plane indicates the pitch and yaw angles and roll angle in indicated by the rib which is the intersection of two right-angle sides. Pitch and yaw angles measurement are implemented by auto-collimation based on reticule and roll angle measurement is measured based on moire fringe. Roll angle measurement is separated from pitch and yaw by using two light sources with different frequencies. Any small change of pitch and roll angles will induce the shift of the reticule image after reflecting by inclined plane. And any small roll angle will induce a change in moire fringe width that is generated by scale grating image which is reflected by the prism and index grating. The math model of this method is built up and error analysis is presented. The theoretical calculation results show that the proposed method is feasible and can achieve high accuracy. 2009 SPIE.