参考资料：https://blog.csdn.net/u013468614/article/details/105619740
运行：
roscore
roslaunch astra_camera astra.launch
报错：
Setting auto_focus is not supported
Setting focus_absolute is not supported
没解决，码一下以后试试别的方法
原文：https://www.cnblogs.com/polipolu/p/13192959.html