I am trying to make a 3D scanner based on turntable. This 3D scanner should create a point cloud model to meause of object length, hight and depth. I am working with realsense d435 RGBD camera. While turntable is rotating, I get the point clouds of object that wants to scan. My question is that how can I join these point clouds that has different rotation angle.

我正在尝试制作一个基于转盘的3D扫描仪。这台3D扫描仪应该创建一个点云模型，以测量物体的长度、高度和深度。我正在使用RealSense d435 RGBD摄像头。当转盘旋转时，我得到了想要扫描的物体的点云。我的问题是，我如何连接这些旋转角度不同的点云。

My steps are:

我的步骤是：

1. Get the point cloud of object. ( I already got it)

   
   



2. Transform the axes of point cloud to world coordinate system. I mean when I import it to meshlab. It should be on xy axis. I made it to)

   
   



3. Use rotation matrix to rotate the point cloud data for real position. I mean, I get the point cloud data that has 90 degree angle from turntable. When I try the rotate it about z axis, it rotates. But the point clouds has 0 degree angle and 90 degree angle doesnt match.

   
   

How can I get over from this problem?

我怎样才能摆脱这个问题呢？