1.ROS安装及环境变量设置：
https://github.com/udacity/didi-competition/blob/master/docs/GettingStarted.md
2.在 RVIZ显示image ，radar ，以及Lidar数据
（1）安装激光雷达驱动Install the Velodyne package for your version of ROS (Indigo in this example)：
sudo apt-get install ros-indigo-velodyne
（2）rosrun velodyne_pointcloud cloud_node _calibration:=/opt/ros/indigo/share/velodyne_pointcloud/params/32db.yaml
（3）roscore
（4）rosbag play /{path-to-file}/bagfile_name.bag
（5）rviz
（6）