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基于自动原位校准的大型飞机构件装配过程三维微位移监测系统 Article

贾振元, 梁冰, 刘巍, 刘坤, 马建伟

《工程（英文）》 2022年第19卷第12期页码 105-116 doi: 10.1016/j.eng.2021.02.023

摘要：本文提出了一种广泛适用的基于接近传感器的高精度在线3D微位移监测方法和系统，以及相应的原位校准方法，可应用于飞机装配过程中遇到的各种极端工作条件，如紧凑和遮挡的空间。然后，结合空间变换原理和加权优化校准方法，获得高精度外部参数。最后，针对尾翼装配过程开展了校准和监测实验。PBP 的校准精度在X、Y 方向优于±10 μm，在Z 方向优于±2 μm，UDV 的校准精度优于0.07&总体而言，本文为基于接近传感器的3D微位移监测的建模和校准提供了新的见解，并为飞机装配过程中紧凑空间内的几何测量提供了一种高精度、高效率、低成本的技术手段。

关键词：飞机制造装配校准状态监测位移测量

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基于5 μm厚向列相液晶的高效圆极化相控阵系统的设计、校准和实验验证 Article

Xin Yu Wu,Fengshuo Wan,Hongyuan Feng,Shichao Jin,Chong Guo,Yu Wei,Dunge Liu,Yuqian Yang,Longzhu Cai,Zhi Hao Jiang,Wei Hong

《工程（英文）》 2024年第32卷第1期页码 70-82 doi: 10.1016/j.eng.2023.08.013

摘要：

This paper presents a systematic investigation and demonstration of a K-band circularly polarized liquid-crystal-based phased array (LCPA), including the design, over-the-air (OTA) in-array calibration, and experimental validation. The LCPA contains 16 phase-shifting radiating channels, each consisting of a circularly polarized stacked patch antenna and a liquid-crystal-based phase shifter (LCPS) based on a loaded differential line structure. Thanks to its slow-wave properties, the LCPS exhibits a maximum phase-shifting range of more than 360° with a figure of merit of 78.3°·dB⁻¹ based on a liquid crystal layer with a thickness of only 5 μm. Furthermore, an automatic OTA calibration based on a state ergodic method is proposed, which enables the extraction of the phase–voltage curve of every individual LCPA channel. The proposed LCPA is manufactured and characterized with a total profile of only 1.76 mm, experimentally demonstrating a scanned circularly polarized beam from −40° to +40° with a measured peak gain of 12.5 dBic and a scanning loss of less than 2.5 dB. The bandwidth of the LCPA, which satisfies the requirements of port reflection (|S₁₁|) < −15 dB, an axial ratio (AR) < 3 dB, beam squinting < 3°, and a gain variation < 2.2 dB, spans from 25.5 to 26.0 GHz. The total efficiency is about 34%, which represents a new state of the art. The use of the demonstrated low-profile LCPA to support circularly polarized scanning beams, along with the systematic design and calibration methodology, holds potential promise for a variety of millimeter-wave applications.

关键词： Circularly polarized Liquid crystal Liquid-crystal-based phased array (LCPA) Phase shifter Over-the-air (OTA) calibration