基于毫米波感知的形变及振动多点同步测量理论与方法

Theory and method of multi-point synchronous deformation and vibration measurement based on millimeter-wave sensing

虽然加速度计、视觉和激光传感等技术已在形变及振动测量中得到广泛而成熟的应用,但大型工程结构的多点同步高精度形变及振动测量依然是挑战难题.利用毫米波线性调频连续波雷达,发展了一种非接触式形变及振动测量新方法和技术,建立了基于毫米波感知的多点同步形变及振动测量理论与方法.从多目标感知的基带信号模型出发,系统阐述了毫米波多点测振原理和振动信息反演提取方法,开发了原型测试系统,搭建了测试实验平台,与激光位移传感器开展了对比测试研究,验证了毫米波多点测振原理与方法的准确性.基于毫米波测振原型系统,对我国某型航天装备的细长铰接柔性杆结构开展了多点同步振动测量和模态辨识试验,并开展了户外大型桥梁结构的动态响应监测研究.结果显示,基于毫米波感知的振动测量方法能够便捷而准确地提取多目标的振动位移时域信息,为大型工程结构的力学性能测试与健康监测等提供一种新的非接触式多点同步形变及振动测量方法与途径.

Although accelerometer-,vision-,and laser-based sensing technologies are widely used in deformation and vibration measurements,the multi-point simultaneous deformation and vibration measurement of large-scale structures with high accuracy remains a challenge.Herein,we developed a novel technology for contactless deformation and vibration measurement using millimeter-wave(mmWave)linear frequency-modulated continuous wave radar,establishing the theory and method for multi-point simultaneous deformation and vibration measurement based on mmWave sensing.The principle of mmWave multi-point vibration measurement and a method of displacement extraction were systematically described using the baseband signal model of multi-target perception.We built a prototype of the proposed mmWave vibration measurement system and a platform for simulated vibration tests.The accuracy of the mmWave multi-point vibration measurement technology was verified and compared with that of laser displacement sensors.Using the prototype system,we conducted experiments on the multi-point synchronous vibration measurement and model identification of the slender hinged flexible rod structure of a certain aerospace equipment in China and then described the dynamic response monitoring of a large bridge structure.Results showed that the deformation and vibration measurement method based on mmWave sensing developed in this work could conveniently and accurately extract the time domain information of multi-target vibration displacements.Our work provides an innovative method and approach for non-contact multi-point synchronous deformation and vibration measurements that could be applied to the mechanical performance test and health monitoring of large structures.