Hand-Eye System Configurations
When it comes to the location of the camera in a vision-guided robotic system, there are two distinct standard configurations: eye-to-hand and eye-in-hand.
此配置是将相机稳固地安装在机器人的末端执行器上，并跟随机器人一起移动。最常见的安装方式是将相机固定在工具法兰或工具上。
The advantage of this system lies in its flexibility. If a larger FOV is required, the robot can pull back and do the imaging from afar. Imaging an object from multiple viewpoints allows a more complete 3D model (possibly a full 360-degree model). It can also change the viewpoint of the camera to look from a different angle. Another advantage of this system configuration is the absence of potential object occlusions caused by the robot.
这种配置的一个缺点是必须通过仔细控制机器人的加速度来避免碰撞。这是为了避免损坏工作环境、相机或机器人。手臂安装的另一个缺点是，当机器人不在可成像的位置时，相机无法用于图像采集，例如，当机器人在交付已拾取的零件时。此外，机器人必须在相机捕获3D图像之前停止移动并保持稳定。最后，相机的重量减少了机器人用于安装夹具和抓取物体的有效负载。
这种配置的系统在机器人单元中有一个固定安装的相机，用于观察机器人的工作空间。
该系统配置的优点是由于相机距离机器人的拾取工作区域相对较远，因此机器人不太可能与之发生碰撞。该系统配置的另一个好处是，可以在机器人移动的同时执行图像采集，这意味着可能会缩短循环时间。
The downside is that the robot arm may occlude the view of the objects by moving between them and the camera. This can then negatively affect the cycle times. To prevent it from happening, it is necessary to use smart motion planning and synchronize robot motion and image acquisition, which is not trivial. This system is also less flexible because the camera is static and has a constant viewpoint. This means that the FOV cannot be changed and the accuracy of image measurements cannot be increased when required. Finally, there is an extra effort in terms of building the robot cell as it requires a mechanical structure for a camera to be mounted on.
我们在本篇教程介绍了系统配置，接下来我们将确定 手眼标定的问题.