參考：

報錯資訊：

1、E: 未發現軟體包 libgazebo9-dev

2、執行 gazebo， 報錯：Error [Node.cc:90] No namespace found
    解決辦法：雖然命令窗會出現這個資訊，但是等個1 分鐘還是會出現 Gazebo 的world 視窗的。

Gazebo try to collect models from http://gazebosim.org/models but there 's something wrong... the folder ~/.gazebo/models does not exist and Gazebo simulator can not start. 

解決辦法:Here's a bit more simple solution: run $ wget -r -R "index\.html*" http://old.gazebosim.org/models/ to get all models from gazebosim and copy them into ~/.gazebo/models folder (after you mkdir modelsinside ~/.gazebo) and everything will be ok.

啟動 Gazebo 的方式：

• Launch both the server and client together

  rosrun gazebo_ros gazebo
   
  

• Launch the Gazebo server only

  rosrun gazebo_ros gzserver
  

• Launch the Gazebo client only

  rosrun gazebo_ros gzclient
  

• Launches the Gazebo server only, in debug mode using GDB

  rosrun gazebo_ros debug
  

• Additionally, you can start Gazebo using roslaunch

  roslaunch gazebo_ros empty_world.launch