激光在线测厚振动分析与精度优化

Vibration Analysis and Precision Optimization of Laser Online Thickness Measurement

摘要:

激光测厚具有安全可靠、测量精度高、测量范围大等优点,广泛应用于纸张、电池极片等薄膜类材料厚度的在线测量。带材宽幅方向扫描测厚时由于扫描架往复运动会产生机械振动,影响在线测厚精度。针对该问题,以锂离子电池极片厚度测量为例,使用双激光差动式测厚平台对电池极片和铜箔分别进行厚度测量,然后对测厚数据进行频谱分析,探究其振动规律的相似性,并基于频谱分析结果采用滑动带阻滤波方式对测厚数据进行处理,滤波后极片和铜箔的厚度极差分别降低了33.4%和73.8%,有效过滤了机械振动导致的测量误差,可满足极片和铜箔厚度测量的精度要求。

Abstract:

Due to the advantages of safety and reliability, high accuracy and large range, laser thickness measurement is widely used in online measurement of film thickness such as paper and battery pole pieces. Scanning thickness measurement of the strip in the wide direction inevitably introduces mechanical vibration, which causes deviations in the measurement results. The lithium-ion battery pole piece was taken as an example to analyze and optimize this problem. First, the thickness of the battery pole piece and the copper foil was measured with differential thickness measurement system, then the spectrum of the battery pole piece and the copper foil was analyzed, and the similarity of the vibration laws was explored. Finally, based on the spectrum analysis, a filter was designed to process the thickness measurement data. After filtering, the range of the pole piece and copper foil are reduced by 33.4% and 73.8%, respectively, thus the thickness measurement accuracy can meet the requirements.