单色光干涉面接触润滑膜厚在线测量

提出了滑块-玻璃盘形成的面接触润滑油膜厚度光干涉在线测量方法。以单色激光为光源,根据油膜厚度变化引起平行干涉条纹平移的物理特征,基于光流和动态时间规整技术构造复合算法,测量干涉图像相邻帧空间域上一维光强曲线的位移,从而得到相邻帧之间的油膜厚度差。从零速度开始记录每一帧干涉图像对应的膜厚变化,实时计算出当前帧对应的膜厚,实现了膜厚的在线测量。当前算法的测量结果与离线膜厚测量结果进行了对比,验证了该系统的测量准确性。进行了阶跃载荷、匀加速及匀减速工况下的膜厚测量,揭示了膜厚变化规律。

On Line measurement of lubricant film thickness in a flat on flat contact by monochromatic interferometry

This paper mainly proposes an on line interference measurement approach of the film thickness in slider on disc conformal contact. With a monochromatic laser, the physical characteristic of the parallel straight interference fringes translation induces by variation of the film thickness. Based on optical flow calculation and dynamic time wrapping technique, a hybrid algorithm is introduced to calculate the displacement of an one dimensional intensity curve across the parallel fringes between two adjacent frames, therefore, the corresponding film thickness change can be obtained. From the start of the test rig, the film thickness variation of each frame is recorded and the on line film thickness measurement is achieved. The film thickness by the presented approach is validated by its good correlation with that by the old off line method. With the new measurement system, the transient film thickness is measured in real time under conditions of step loads, uniform acceleration and deceleration, and some characteristics of film building are demonstrated.