Ubuntu16.04 安装ROS Kinetic时，有两句命令总是报错，记录一下解决方法。
$sudo rosdep init出现报错
ERROR: cannot download default sources list from: https://raw.githubusercontent.com/ros/rosdistro/master/rosdep/sources.list.d/20-default.list Website may be down. $rosdep update出现报错
ERROR: unable to process source [https://raw.githubusercontent.com/ros/rosdistro/master/rosdep/osx-homebrew.yaml]: <urlopen error timed out> (https://raw.githubusercontent.com/ros/rosdistro/master/rosdep/osx-homebrew.yaml)方法一：最好用的方法就是用ssr，并在终端也配置好：
export http_proxy=http://ip:端口 export https_proxy=http://ip:端口方法二：
$sudo gedit /etc/hosts最下边一行加上：
199.232.28.133 raw.githubusercontent.com然后保存重试
方法三：在前两个方法都不行的情况下，使用最麻烦的方法，手写20-default.list文件，拷贝.ros文件夹。
第一步：手写20-default.list文件：
$sudo mkdir -p /etc/ros/rosdep/sources.list.d $cd /etc/ros/rosdep/sources.list.d $sudo gedit 20-default.list复制以下内容粘贴进去保存
# os-specific listings first yaml https://raw.githubusercontent.com/ros/rosdistro/master/rosdep/osx-homebrew.yaml osx # generic yaml https://raw.githubusercontent.com/ros/rosdistro/master/rosdep/base.yaml yaml https://raw.githubusercontent.com/ros/rosdistro/master/rosdep/python.yaml yaml https://raw.githubusercontent.com/ros/rosdistro/master/rosdep/ruby.yaml gbpdistro https://raw.githubusercontent.com/ros/rosdistro/master/releases/fuerte.yaml fuerte # newer distributions (Groovy, Hydro, ...) must not be listed anymore, they are being fetched from the rosdistro index.yaml instead第二步：拷贝.ros文件夹
rosdep update命令会生成一个.ros文件夹，我将已经生成好的上传了，将我附上的资源下载到你的home目录，解压，将文件夹名字改为.ros，然后就可以进行正常使用ROS了。
