命令行输入gazebo --verbose没有图形显示！找不到出错信息！
[Msg] Waiting for master.
Gazebo multi-robot simulator, version 9.8.0.hbp.3.0.5
Copyright (C) 2012 Open Source Robotics Foundation.
Released under the Apache 2 License.
http://gazebosim.org
[Msg] Waiting for master.
[Msg] Connected to gazebo master @ http://127.0.0.1:11345
[Msg] Publicized address: 172.27.18.126
找到GAZEBO_MODEL_PATH用git下载所有模型后仍然没有效果！
原因可能是~/.bashrc中环境变量设置的问题
export DISPLAY=192.168.0.103:0 #改成自己主机的网络IP地址
export LIBGL_ALWAYS_SOFTWARE=1 #启动软件渲染
export LIBGL_ALWAYS_INDIRECT= #这里一定要空！
这样就可以正常运行了！