Cartographer—ROS中的安装
前面几步没什么好说的，个人是看的是官网https://google-cartographer-ros.readthedocs.io/en/latest/中部分，也可参考http://blog.exbot.net/archives/2852k中记录，这里主要记录一下关于引用库Ceres的步骤，都知道XX的原因，可苦了国内做研究的众人员，其实部分也相当简单，如果从谷歌git中的库下载有问题，可以自己另外从源码网址下载。
一、在安装cartographer前，需要系统满足如下的要求：
- 64-bit, modern CPU (e.g. 3rd generation i7)
- 16 GB RAM
- Ubuntu 14.04 (Trusty)
- gcc version 4.8.4
- ROS Indigo
二、安装过程及命令：
# Install wstool and rosdep.
sudo apt-get update
sudo apt-get install -y python-wstool python-rosdep ninja-build
# Create a new workspace in 'catkin_ws'.
mkdir catkin_ws
cd catkin_ws
wstool init src
# Merge the cartographer_ros.rosinstall file and fetch code for dependencies.
wstool merge -t src https://raw.githubusercontent.com/googlecartographer/cartographer_ros/master/cartographer_ros.rosinstall
wstool update -t src
主要在上面这步，由于源码中引用库Ceres，我用的软件为Lantern(使用步骤http://www.cnblogs.com/ikuyka/p/5647880.html)，但仍提示
fatal: unable to access 'https://ceres-solver.googlesource.com/ceres-solver.git/': Failed to connect to ceres-solver.googlesource.com
port 443: 连接超时
Exception caught during install: Error processing 'ceres-solver' : [ceres-solver] Checkout of https://ceres-solver.googlesource.com/ceres -solver.git version 1.12.0rc4 into /home/jack/catkin_ws/src/ceres-solver failed.
解决办法，到提示这些错误之前，cartographer与cartographer_ros部分已经配置完成，关于这个引用库可以用命令
git clone https://github.com/ceres-solver/ceres-solver
OK....这样就搞定了...
# Install deb dependencies.
rosdep update
rosdep install --from-paths src --ignore-src --rosdistro=${ROS_DISTRO} -y
# Build and install.
catkin_make_isolated --install --use-ninja
source install_isolated/setup.bash
后续...