利用数字视频技术测量旋转速度的研究

Researching of Measurement Angle Velocity Based on Video Techniques

基于视频的测量系统,具有非接触,安装维护简捷而且费用低等特点;本研究的目标就是利用摄像机对测量对象进行视频采集,然后提取相邻两帧图像;当运动对象进行简单的单轴旋转时,利用Hough变换(或Rando变换)技术进行直线的角度检测;计算出相邻帧的角度差,根据间隔时间,计算出角速度;当球体进行多轴旋转时,根据球体标志投影,结合三维空间刚体运动模型,利用一组特征点坐标,采用两步迭代交替估计运动参数,求得运动物体相对三维空间各个轴的角速度;并对特殊已知结构参数的运动物体给出了简化的计算方法,通过实验表明本方法测量结果满足要求。

Video-based measuring system is the non-contact and the maintenance of the method is simple and low cost.The goal of this study is using camera to get the rotational object＇s records,and then extract the two adjacent frames from the video records.For single-axis rotation of the object,we calculate the angle of the line in the each image by the Hough Transform（or Radon Transform） techniques.In this way,the angle difference of the adjacent frames can be calculated and the angular velocity also can be easy gotten.For the multi-axis rotation of the sphere,We can calculated the projection of the sign of the sphere according to spherical surface equation and calculated the angle difference of the each axis between the adjacent two frames and got the angular velocity of the three axes.The result of the measurements is satisfactory by the experiment.