工业相机自热引起像点漂移模型与补偿方法

Model and compensation method of image point drift caused by self-heating of industrial camera

  • 摘要: 为减小视觉测量中温度对工业相机像点坐标的影响,对相机自热引起的像点漂移进行研究,提出一种针对工业相机热致像点漂移补偿方法。通过Ansys Workbench对工业相机模型进行有限元仿真分析,得出工业相机自热会引起成像光路变化和传感器膨胀变化,定量分析光路变化与传感器膨胀对像点坐标的影响,建立图像像点漂移补偿模型。大量实验表明,利用模型补偿后的像点漂移误差从0.4 \! \sim \! 0.6 pixel降低到0.1\! \sim \! 0.2 pixel,与采用硬件热控方式达到的像点漂移抑制效果相当。但是相对于热控装置,使用模型进行补偿的方法具有结构简单、成本低的明显优势。该研究提出的温度补偿模型为减小视觉测量中相机自热导致的像点漂移误差提供了理论依据。

     

    Abstract: In order to reduce the influence of temperature on the image point coordinates of industrial cameras in visual measurement, the image point drift caused by the self-heating of the camera was studied, and a compensation method for the thermal image point drift of industrial cameras was proposed. The finite element simulation analysis of the industrial camera model through Ansys Workbench shows that the self-heating of the industrial camera will cause the imaging optical path change and sensor expansion change, quantitatively the influence of the optical path change and sensor expansion on the image point coordinates was analyzed, and the image point drift compensation model was established. A large number of experiments have shown that the image point drift error compensated by the model is reduced from 0.4-0.6 pixel to 0.1-0.2 pixel, which is equivalent to the image point drift suppression effect achieved by hardware thermal control. However, compared with the thermal control device, the method of using the model for compensation has obvious advantages of simple structure and low cost. The temperature compensation model proposed in this research provides a theoretical basis for reducing the image point drift error caused by the self-heating of the camera in the visual measurement.

     

/

返回文章
返回