针对传统接触式振动测量方法的缺点,提出一种基于视觉测量的太阳翼模态参数在轨辨识方法.具体过程包括相机标定、标志点检测、三维坐标解算和模态辨识等.利用两台相机和一台计算机构成的双目立体视觉测量系统进行了地面试验,测量得到了太阳翼测点处的振动位移响应,然后采用ERA算法辨识出了真实太阳翼的两阶主要模态参数.通过与激光测振仪测量结果进行比较,验证了上述方案的有效性.实验表明,视觉测量方法设备简单,灵活性高,是一种理想的在轨振动测量方法.
Aiming at the disadvantages of traditional contact vibration measurement, an on-orbit modal parameters identification method is presented based on photogrammetry for solar arrays. The specific process includes camera calibration, marking point detection, 3D coordinate calculation and modal identification. A binocular stereo vision measurement system made of two cameras and a computer are used for the ground test. The vibration displacement response of measuring points on solar array is obtained. ERA algorithm is used to identify the two main modal parameters of solar array. By comparing with the results measured by laser vibrometer, the effectiveness of the scheme is verified. The experiment shows that the photogrammetry is an ideal method in vibration measurement, which has high flexibility and requires for simple devices.