基于机器微视觉的超声辐射力测量技术

针对微构件在超声辐射力场中所受的辐射力，提出了一种基于机器微视觉的非接触式微力精密测量方法.在研究检测对象刚体平面运动特点和分析传统数字图像相关算法局限性的基础上，采用基于圆周窗口等分角采样的特征提取方法，将二维图像中刚体的相角位置信息表征为一维采样时序信号，并通过基于小波变换的广义相关算法来估计位移前后特征序列的时延，得到刚体的旋转角位移，从而利用力与运动量的相互关系确定出作用于微构件的超声辐射力.实验结果表明，该技术具有速度快、精度高的检测特点，并突破了传统方法仅适合于检测平稳信号在非相关干扰噪声环境下应用的限制，具有较宽的应用范围.

Measuring technique of ultrasonic radiation force based on machine micro-vision

A new non-contact precision measuring method of radiation force acted on the micro-component in ultrasonic radiation field based on machine micro-vision was presented. After analyzing the characteristic of the rigid plane motion and the shortcomings of classical digital image correlation algorithms, the phaseangle position of the rigid body in the 2D image was characterized by 1D sequence signals using the method of equiangular sampling feature extraction based on circle windows. Then the generalized correlation algorithm for estimation of time delay based on wavelet transform was used to acquire the angular displacement. Finally the ultrasonic radiation force acted on the micro-component was determined by the relation between force and motion. The experimental results indicate that the presented technique has fast speed and high precision, and breaks through the restriction that the conventional methods can only applied to measure the stationary signal with non-correlative noise.