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在国产化、技术自主化的大型飞机项目上,对孔位精度的标准正逐步升高,钻头的垂直度又是这一标准中最受关注的条件。机器人自动钻铆系统工作时,所产生的装配误差、磕碰、偏移等状况,不仅降低了制造及检测的准确度,还影响了整个结构件的疲劳性能。针对这一问题,提出了基于多激光传感器装配的自适应自由曲面法线检测技术,搭建了以该方法进行姿态找正的数学模型,并研究了检测装置的标定方法及流程。同时,着重讨论了在自适应方法检测时,利用电子经纬仪等装置进行误差补偿的相关技术。该方法的验证实验结果显示,多组实验数据均达到了法向精度<±0.5°的关键技术指标要求,找正后的法线平均偏差值为0.0667°。该方法能有效补偿在制孔工作中所产生的相关误差,进一步提高机器人的定位精度及法线方向检测精度。 相似文献
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Influence of Zr_(50)Cu_(50) thin film metallic glass as buffer layer on the structural and optoelectrical properties of AZO films 下载免费PDF全文
Aluminum-doped ZnO(AZO) thin films with thin film metallic glass of Zr(50)Cu(50) as buffer are prepared on glass substrates by the pulsed laser deposition. The influence of buffer thickness and substrate temperature on structural, optical, and electrical properties of AZO thin film are investigated. Increasing the thickness of buffer layer and substrate temperature can both promote the transformation of AZO from amorphous to crystalline structure, while they show(100)and(002) unique preferential orientations, respectively. After inserting Zr(50)Cu(50) layer between the glass substrate and AZO film, the sheet resistance and visible transmittance decrease, but the infrared transmittance increases. With substrate temperature increasing from 25℃ to 520℃, the sheet resistance of AZO(100 nm)/Zr(50)Cu(50)(4 nm) film first increases and then decreases, and the infrared transmittance is improved. The AZO(100 nm)/Zr(50)Cu(50)(4 nm) film deposited at a substrate temperature of 360℃ exhibits a low sheet resistance of 26.7 ?/, high transmittance of 82.1% in the visible light region, 81.6% in near-infrared region, and low surface roughness of 0.85 nm, which are useful properties for their potential applications in tandem solar cell and infrared technology. 相似文献
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详细研究了沉积在Poly(9-vinylcarbazole)(PVK)薄膜上的8-羟基喹啉铝(Alq3)薄膜的形态结构对电致发光器件ITO/PVK/Alq3/Mg-Ag性能的影响。研究结果表明:发光层(Alq3层)的表面形貌极大地影响发光层和金属阴极的接触面积,从而影响器件的电流-电压特性。发光层的表面越均匀连续,发光层和金属阴极的接触面积就越大,通过器件的电流就越大。在三种条件的器件中,基底温度为438K时制备的Alq3薄膜所对应的器件的量子效率最高,298K制备的器件的率效次之,77K制备的器件的效率最差。 相似文献
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Organic light emitting diodes using magnesium doped organic acceptor as electron injection layer and silver as cathode 下载免费PDF全文
Organic light emitting diodes employing magnesium doped electron
acceptor 3, 4, 9, 10 perylenetetracarboxylic dianhydride
(Mg:PTCDA) as electron injection layer and silver as cathode were
demonstrated. As compared to Mg:Ag cathode, the combination of
the Mg:PTCDA layer and silver provided enhanced electron
injection into tris (8-quinolinolato) aluminium. The device with
1:2 Mg:PTCDA and Ag showed an increase of about 12% in the
maximum current efficiency, mainly due to the improved hole-electron
balance, and an increase of about 28% in the maximum power
efficiency, as compared to the control device using Mg:Ag
cathode. The properties of Mg:PTCDA composites were studied as
well. 相似文献
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Organic Light-Emitting Diodes with Magnesium Doped CuPc as an Efficient Electron Injection Layer 下载免费PDF全文
Bright organic electroluminescent devices are developed using a metal-doped organic layer intervening between the cathode and the emitting layer. The typical device structure is a glass substrate/indium-tin oxide (ITO)/copper phthalocyanine (CuPc)/N,N'-bis-(1-naphthl)-diphenyl-1,1'-biphenyl-4,4'-diamine (NPB)/Tris(8-quinolinolato) aluminum(Alq3)/Mg-doped CuPc/Ag. At a driving voltage of 11 V, the device with a layer of Mg-doped CuPc (1:2 in weight) shows a brightness of 4312cd/m^2 and a current efficiency of 2.52cd/A, while the reference device exhibits 514 cd/m^2 and 1.25 cd/A. 相似文献
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为了解决“猫眼”目标在夜晚环境下难识别的问题,提出了一种基于归一化中心矩的轮廓匹配“猫眼”目标识别方法。首先利用中值滤波对图像进行去噪,采用固定阈值分割完成了对图像的分割,使得“猫眼”目标与部分背景分离,使用Roberts边缘检测提取出了所有物体的边缘,最后采取了基于归一化中心矩的轮廓匹配算法,该算法不受平移和放缩的影响,提取出了图像中的所有圆形目标,并利用面积判别识别了真实目标,对识别出的目标绘制最小外接圆,利用圆心坐标对其定位。通过对不同光照强度下的“猫眼”图像进行实验与对比,验证了该方法的可行性,并通过目标识别评价指标验证了该方法的有效性。实验结果表明,该方法的全局准确率可达92.1%,可以在夜晚环境不同光照强度下成功地对“猫眼”目标进行识别。 相似文献
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采用有限元方法分析出涡轮风扇支板个数为10时发生断裂的原因是高周疲劳破坏,并且叶片发生疲劳的主要原因是支板个数设置不合理.通过Campbell图分析出了两种优化方案,即支板个数为3和19.从共振点个数、应力水平及理论寿命来看,支板个数为19均优于3.分别对支板个数为10和3的叶片进行疲劳寿命模拟计算,结果表明,两者的疲劳寿命均较短,不符合工程实际要求,最终确定支板个数19为优化方案. 相似文献