数字图像相关方法的桥梁挠度仪的温度补偿

Temperature compensations for bridge deflection meter by using of digital image correlation method

基于数字图像相关方法的桥梁挠度仪会因相机温度变化而引起一定的测量误差,为了补偿因相机温度变化而引起的挠度测量误差,先通过实验实测了相机温度变化与测量误差之间的数值关系,并发现相机温度变化与测量误差之间存在一定的线性关系;然后通过直线拟合方法,找出相机温度变化与测量误差之间的具体函数关系,并据此对挠度测量过程进行了实时温度补偿。实验表明,经过温度补偿后的挠度测量,其测量误差大为降低,降幅可达85.3%。

The changes of the camera temperature of the bridge deflection meter by use of digital image correlation method would cause some errors.In order to compensate the deflection measurement errors caused by the changes of the camera temperature,this paper first measured the numerical relationship between the variations of the camera temperature and the errors through experiments,and found that there was a linear relationship between the variations of the camera temperature and the errors.Then the function between the variations of the camera temperature and the errors was found out by line fitting method.According to the function,the real-time compensations were made for the deflection measurement.The experiments show that the deflection measurement errors are greatly reduced by 85.3%after the temperature compensations.