a few tools for using ros
(before you try to use these tools, make sure you bash the install file to install all tools)
bash publish_tf_install.bash
roscore
rosparam set use_sim_time true
rosbag play --pause --clock [rosbag file]
source ros_tools_ws/devel/setup.sh
rosrun publish_tf publish_tf_node
rviz (add pointcloud2 to listen the lidar topic)
roscore
rosbag play --pause --clock [rosbag file]
source ros_tools_ws/devel/setup.sh
cd [path which you want to save all pcd files]
rosrun rosbag_to_pcd rosbag_to_pcd_node