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ros noetic 安装 cartographer

1.1 安装依赖项

首先，我们需要安装一些依赖项。在终端中输入以下命令：

sudo apt-get update
sudo apt-get install -y python-wstool python-rosdep ninja-build

1.2 安装 Cartographer ROS

接下来，创建一个新的工作空间并获取 Cartographer ROS 代码：

mkdir -p ~/catkin_ws/src
cd ~/catkin_ws/src
git clone https://github.com/cartographer-project/cartographer_ros.git

这部分也可以这样：

mkdir catkin_ws
cd catkin_ws
wstool init src
wstool merge -t src https://raw.githubusercontent.com/googlecartographer/cartographer_ros/master/cartographer_ros.rosinstall

1.3 安装所有必要的依赖项

使用 rosdep 安装所有必要的依赖项：

cd ~/catkin_ws
rosdep update
rosdep install --from-paths src --ignore-src --rosdistro=${ROS_DISTRO} -y

我使用的是noetic版本也就是ubuntu20.04，在这里这条指令会有问题，替换为下条指令

rosdep install -i --from-path src --ignore-src -r

1.4 构建 Cartographer ROS

cd ~/catkin_ws
catkin_make_isolated --install --use-ninja

我在这里出现问题：
问题 ① absl库报错

CMake Error at CMakeLists.txt:32 (find_package):
  By not providing "Findabsl.cmake" in CMAKE_MODULE_PATH this project has
  asked CMake to find a package configuration file provided by "absl", but
  CMake did not find one.

  Could not find a package configuration file provided by "absl" with any of
  the following names:

    abslConfig.cmake
    absl-config.cmake

  Add the installation prefix of "absl" to CMAKE_PREFIX_PATH or set
  "absl_DIR" to a directory containing one of the above files.  If "absl"
  provides a separate development package or SDK, be sure it has been
  installed.

解决方法：

sudo apt-get install stow

去catkin_ws/src/cartographer/scripts路径下

sudo chmod +x install_abseil.sh
./install_abseil.sh

1.5 更新环境变量

source install_isolated/setup.bash

cartographer建图测试

下载示例包（例如Deutsches Museum(德意志博物馆)的2D和3D背包系列）到~/Downloads（这里下载到哪时无所谓的），并使用roslaunch来调出演示：

wget -P ~/Downloads https://storage.googleapis.com/cartographer-public-data/bags/backpack_2d/cartographer_paper_deutsches_museum.bag

这个我下载不下来，会有问题，我最后从网上随便找了一个bag尝试的

roslaunch cartographer_ros demo_backpack_2d.launch bag_filename:=${HOME}/Downloads/cartographer_paper_deutsches_museum.bag

结果展示：