基于机器视觉的柔性臂振动测量研究

Vibration measurement of flexible beam based on machine vision

针对柔性结构振动测量研究的需要,设计了一种基于机器视觉的非接触式柔性臂振动测量系统.该系统在柔性臂上安装光源标记供振动测量,采用工业CCD相机采集振动图像,基于多线程技术设计的用户软件实现了振动参数的测量.应用Otsu阈值分割法提取光斑,获得光斑的质心位置;通过坐标转换计算出柔性臂光斑处的动态位移.实验结果表明:所设计的基于机器视觉的振动测量系统简单易实现、实时性好,图像的处理速度完全能够满足振动测量的需要,为机器视觉系统应用于柔性结构振动测量和主动振动控制提供了技术手段.

In order to meet the need of vibration measurement of flexible structure,a non-contact vibration measurement system of a flexible beam was designed based on machine vision.In the system, a light source was attached to the flexible beam for vibration measurement and an industrial CCD camera was used to acquire digital image of vibration.The vibration parameters of flexible beam were obtained by user software based on multithread technique.The light spot was detected by using threshold segmentation method of Otsu,and then the mass center was acquired.By means of coordinate transformation,the dynamic displacement of light spot on the flexible beam was calculated.Experiment results show that the system designed for vibration measurement based on machine vision is simple and easy to implement with good real-time performance.The image processing speed can satisfy the requirements of vibration measurement.It provides a technical means to apply the machine vision system to vibration measurement of flexible structure and active vibration control.