|Alternative Title||Research on Measurement Method of Aircraft Surface Manufacturing Quality Based on Digital phase-shifting interferometry|
|Keyword||数字相移 相位误差分析 飞机表面 铆钉接缝检测 反投影显示|
|Place of Conferral||沈阳|
飞机表面主要是由包围在机翼骨架外围的蒙皮构成，其表面制造质量对飞机的气动特性、飞行安全性、飞行成本以及隐身性等都具有重大影响。因此，在飞机装配制造以及出厂交付时，需要对其表面制造质量进行严格检测。影响飞机表面制造质量的因素主要包括：飞机翼身对接面、蒙皮与蒙皮、蒙皮与表面紧固件之间形成的阶差与间隙等。目前国外已经有部分成熟的数字化自动检测仪器用于相关领域，而国内企业仍主要借助检测塞尺、样板、模胎、专用检验工装、量具、人工观测等手段，对飞机表面质量进行检测，这种检测方法是基于模拟量的合格与不合格，难以精确地描述零部件状态，并且效率低，自动化程度不高，人为因素多，精度没有保障。因此，迫切需求一种数字化测量技术对飞机表面制造质量进行快速检测，以保障飞机的快速制造与出厂交付。本文基于数字相移法，对飞机表面制造质量检测技术进行了研究，主要研究内容如下：1. 对基于数字相移的高精度三维测量方法进行了研究，首先根据数字相移技术原理，搭建了一套三维扫描实验平台，然后对数字相移技术中涉及到的关键问题-相位求解问题，进行了深入研究，针对多频外差原理解相后存在相位跳跃误差的问题，提出了一种改进算法，避免了相位跳跃的发生；并对由物体表面光学特性不均匀所引起的相位误差的成因进行了深入分析，提出了一种根据物体表面局部反射率进行动态调整投影光栅强度的算法，减小了反射率不均匀对相位求解精度的影响，从而提高了测量精度。2. 对低信噪比图像中铆钉和接缝区域快速识别算法进行了研究。针对铆钉区域，提出了一种将边缘跟踪和霍夫变换结合起来的铆钉区域提取算法，该算法融合了霍夫变换和边缘跟踪算法的优点，既能够检测被噪声淹没的铆钉，又具有较高的检测效率。针对接缝区域，提出了一种基于Steger算法的接缝区域提取方法，该方法简单可靠，可以完成接缝区域的快速检测。3. 通过对铆钉和接缝区域点云特征进行分析，提出了相应的偏差信息分析算法，并针对铆钉和接缝区域特征，设计了相应的标准件，对所提算法的精度进行了验证。4. 针对数字相移检测系统结果显示不够直观的问题，提出了一种利用该系统中的投影仪将测量结果直接投影到被测件表面的可视化显示方法，并对可视化显示原理进行了详细的阐述，针对其中涉及的核心问题-投影仪标定问题，提出了一种简便的投影仪标定方法，可快速完成投影仪参数的标定。实验结果表明，该方法可准确地将检测信息投影到被测件表面，显示结果直观，可大大提高检测效率，不需要对原检测系统做任何硬件改动，因此，具有极大的实用价值。5. 设计开发出了飞机表面制造质量检测原型系统，并通过实验对原型系统可重复性进行了验证。
The surface of the aircraft is mainly composed of the skin that surrounds the periphery of the wing frame. The surface manufacturing quality has a great influence on the aerodynamic characteristics, flight safety, flight costs, and stealth of the aircraft. Therefore, it is necessary to strictly inspect the surface manufacturing quality while manufacturing or assembling the aircraft. The factors influencing the manufacturing quality of the aircraft surface mainly include: the step and gap between the aircraft wing body docking surface, the skin and the skin, the skin and the surface fastener. At present, some commercial digital automatic detection instruments have been used in related fields in foreign countries, while domestic enterprises still mainly rely on measures such as feeler gauges, templates, model tires, special inspection tools, gauges, and manual observations to detect the surface quality of aircraft. This kind of detection methods can only get the result of qualified or unqualified, and it is difficult to accurately describe the status of parts or components. The efficiency of these methods is very low, and the accuracy is not guaranteed. Therefore, there is an urgent need for a digital measurement technology to quickly detect the surface quality of aircraft, so as to ensure the rapid manufacturing and quality of the aircraft. This paper studies the manufacturing quality inspection technology of aircraft surface based on the digital phase-shifting method. The main research contents are as follows: 1. A high-precision three-dimensional measurement method based on digital phase-shifting is studied. Firstly, a set of three-dimensional scanning experiment platform is built according to the principle of digital phase-shifting technology. Then the key problem involved in digital phase-shifting technology, phase unwrapping method, is explored in depth. In order to eliminate the phase jump error of existing phase unwrapping method based on multifrequency heterodyne principle, the improvement of the phase unwrapping method based on multifrequency heterodyne principle is proposed. Then we present a theoretical analysis of phase errors caused by nonuniform surface reflectivity. And based on the analysis, a method to adaptively adjust the maximum input gray level of each pixel in projected fringe patterns to the local reflectivity is proposed to reduce phase errors. 2. The fast recognition algorithms for rivets and seams in low signal-to-noise ratio images are studied. For rivet region, a rivet area extraction algorithm combining edge following and Hough Transform is proposed. The algorithm combines the advantages of Hough transform and edge following algorithm. It not only can detect the rivets that are overwhelmed by noise, but also has high detection efficiency. For the seam area, a seam region extraction algorithm based on the Steger algorithm is proposed. The algorithm is simple and reliable, and the seam area can be quickly detected. 3. By analyzing the features of point clouds in rivets and seams, a corresponding algorithm for extracting error information is proposed. According to the features of rivets and joints, corresponding standard parts are designed and the accuracy of the proposed algorithm is verified. 4. Aiming at the problem that the display result of the digital phase-shifting detection system is not intuitive, a visual display method of projecting the measurement result to the surface of the inspected object is proposed by using the projector in the digital phase-shifting system. The measurement result can be directly projected to the corresponding detection area. Thus, there is a large boost in terms of the intuitive display. Aiming at the core problem of this method-projector calibration, a simple calibration method is proposed, which can quickly complete the calibration of projector’s intrinsic parameters and its relative position with the camera. The experimental results show that the proposed method can accurately project the detection information to the surface of the measured parts, and can display the results intuitively. Thus it can greatly improve the detection efficiency, and does not need any hardware changes to the original detection system. Therefore, it is very useful. 5. Develope a prototype system for aircraft surface manufacturing quality inspection and verify the prototype system through field experiments.
|陈松林. 基于数字相移的飞机表面制造质量检测方法研究[D]. 沈阳. 中国科学院沈阳自动化研究所,2018.|
|Files in This Item:|
|基于数字相移的飞机表面制造质量检测方法研（7696KB）||学位论文||开放获取||CC BY-NC-SA||Application Full Text|
|Recommend this item|
|Export to Endnote|
|Similar articles in Google Scholar|
|Similar articles in Baidu academic|
|Similar articles in Bing Scholar|
Items in the repository are protected by copyright, with all rights reserved, unless otherwise indicated.