前提：
通过以下命令装了ros（内带的gezobo版本是2）
ros-indigo-desktop-full
Setup your computer to accept software from packages.osrfoundation.org:
sudo sh -c 'echo "deb http://packages.osrfoundation.org/gazebo/ubuntu-stable `lsb_release -cs` main" > /etc/apt/sources.list.d/gazebo-stable.list'
Setup keys:
wget http://packages.osrfoundation.org/gazebo.key -O - | sudo apt-key add -
Install Gazebo:
sudo apt-get update
sudo apt-get remove .*gazebo.* && sudo apt-get update && sudo apt-get install gazebo7 libgazebo7-dev
