turtlebot_gazebo world 不能载入model

问题解决：
http://answers.gazebosim.org/question/4399/turtlebot_gazebo-world-not-loading-models/


问题如下，显示一直下载model

Warning [ModelDatabase.cc:356] Getting models from[http://gazebosim.org/models/]. This may take a few seconds.It may take a minute or so to download the models.

If that doesn't work then you may need Gazebo 2.0. Since you are using ROS hydro, which relies on Gazebo 1.9.2, I would recommend against installing Gazebo 2.0. Instead, you can grab the models manually.

wget http://gazebosim.org/models/dumpster/model.tar.gz .

tar xvf model.tar.gz -C ~/.gazebo/models