(ros/navigation) navigation导航中一些重要话题的来源和去路，对理解程序有很大帮助
topic1: cmd_vel Type: 类型
geometry_msgs/Twist Publishers: 发布者 * /move_base Subscribers: 订阅者 * none topic2: /move_base/NavfnROS/plan Type: nav_msgs/Path Publishers: * /move_base Subscribers: * /rviz topic3: /move_base/DWAPlannerROS/global_plan Type: nav_msgs/Path Publishers: * /move_base Subscribers: * /rviz topic4: /move_base/DWAPlannerROS/local_plan Type: nav_msgs/Path Publishers: * /move_base Subscribers: * /rviz
topic5: /move_base/goal Type: move_base_msgs/MoveBaseActionGoal Publishers: * /move_base Subscribers: * /move_base topic6: /move_base_simple/goal Type: geometry_msgs/PoseStamped Publishers: * /rviz Subscribers: * /move_base * /rviz topic7: /move_base/status Type: actionlib_msgs/GoalStatusArray Publishers: * /move_base topic8: /tf Type: tf2_msgs/TFMessage Publishers: * /odometry * /robot_tf_publisher * /amcl Subscribers: * /amcl * /move_base * /rviz
