针对现有算法难以精确配准重叠区域较小的点云,提出一种结合二维序列图像的点云初始配准方法。基于移动式三维测量方法获取实物表面灰度图像及三维数据,根据透视投影原理对相机在点云局部坐标系中的位置进行定位,获取点云到对应相机坐标系的变换矩阵,并以灰度图像的特征点及其匹配点作为匹配对,通过重建序列图像对相机外参数予以全局优化,根据初始配准公式实现点云初始配准。试验结果表明,该算法可正确配准重叠区域较小的点云
针对常规浊度测量方法受背景光影响大的问题,采用了数字锁相放大原理与常规浊度测量相结合的方法对微弱光电信号进行处理。采用数字正交锁相放大技术提取待检测信号的幅值与相位,消除了信号延迟及环境背景光的影响,有效提升该系统检测精度、范围及被检测信号信噪比。通过对系统进行优化,实现了浊度检测仪器的微型化和低成本化。利用所研制微型浊度检测仪器的实际测试实验表明,总体检测精度为±3%FS,测量范围为0～2 00
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