ROS知識（3）----功能包package編譯的兩種方式

ROS的包編譯有兩種方法（我知道的），一種是用rosmake，這種方法簡單；另一種是用catkin_make，這種方法更方便包的管理和開發。這兩種方法都是先建立工作空間workspace（類似於vs下的解決方案，用來管理很多的項目），然后建立包package（類似於vs下的項目），最后利用rosmake或者catkin_make進行編譯和運行。學會第一種方式，再去學習第二種就很簡單了。源碼附在每個小節的后面。

1、rosmake編譯包package

 

1.1、創建工作空間

在開始具體工作之前，首先創建工作空間，並且為工作空間設置環境變量到~/.bashrc中，如果要查看已有的空間路徑，可以用查詢命令

$ echo $ROS_PACKAGE_PATH

你將會看到如下的信息：

/home/horsetail/dev/rosbook:/home/horsetail/catkin_ws/src:/opt/ros/jade/share:/opt/ros/jade/stacks

這里的創建空間實際上就是先建立一個文件夾，然后把文件夾的路徑設置到環境變量~/.bashrc中。例如我們這里創建目錄~/dev/rosbook作為工作空間。

首先執行命令：

$ cd ~
$ mkdir -p dev/rosbook

然后將創建的路徑加入到環境變量中，執行如下命令：

$ echo "export ROS_PACKAGE_PATH=~/dev/rosbook:${ROS_PACKAGE_PATH}" >> ~/.bashrc
$ . ~/.bashrc

這樣，我們就完成了工作空間的配置，注意：ROS安裝的時候，一定要把ROS的環境變量也加到~/.bashrc中。這里還需要把ROS。接下來就是在這個空間下創建包了。

 

1.2、創建包

 可以手動創建包，但是非常的繁瑣，為了方便，最好使用roscreate-pkg命令行工具，該命令行的格式如下：

roscreate-pkg [package_name] [depend1] [depend2] [depend3] ...

命令行包含了要創建包的名字，依賴包。

我們的例子中，創建一個叫mypacakge1的 新包，命令如下：

$ cd ~/dev/rosbook
$ roscreate-pkg mypackage1 std_msgs roscpp rospy

過一會彈出如下的信息，表示創建成功：

Created package directory /home/horsetail/dev/rosbook/mypackage1
Created include directory /home/horsetail/dev/rosbook/mypackage1/include/mypackage1
Created cpp source directory /home/horsetail/dev/rosbook/mypackage1/src
Created package file /home/horsetail/dev/rosbook/mypackage1/Makefile
Created package file /home/horsetail/dev/rosbook/mypackage1/manifest.xml
Created package file /home/horsetail/dev/rosbook/mypackage1/CMakeLists.txt
Created package file /home/horsetail/dev/rosbook/mypackage1/mainpage.dox

Please edit mypackage1/manifest.xml and mainpage.dox to finish creating your package

好了這樣就完成了包的創建，我們發現在mypackage1的目錄下有一個src文件夾，我們接下來就是網這里添加源程序了。

 

1.3、代碼編輯和編譯

 參考ROS官方網站的教程，我們編寫一個編寫簡單的消息發布器和訂閱器 (C++)，即編寫倆個源文件talker.cpp和listener.cpp，並將他們保存到~/dev/rosbook/mypackage1/src目錄中。

代碼理解可以參考ROS_wiki：http://wiki.ros.org/cn/ROS/Tutorials/WritingPublisherSubscriber%28c%2B%2B%29

發布器就是一個說話者talker，/mypackage1/srctalker.cpp代碼如下：

#include "ros/ros.h"
#include "std_msgs/String.h"

#include <sstream>

int main(int argc, char **argv)
{
  ros::init(argc, argv, "talker");

  ros::NodeHandle n;

  ros::Publisher chatter_pub = n.advertise<std_msgs::String>("chatter", 1000);

  ros::Rate loop_rate(10);

  int count = 0;
  while (ros::ok())
  {
    std_msgs::String msg;

    std::stringstream ss;
    ss << "hello world " << count;
    msg.data = ss.str();

    ROS_INFO("%s", msg.data.c_str());


    chatter_pub.publish(msg);

    ros::spinOnce();

    loop_rate.sleep();
    ++count;
  }


  return 0;
}

訂閱者就是一個聽話人listener，他不停地接受talker廣播出來的消息，並顯示到屏幕上，/mypackage1/srclistener.cpp的代碼為：

include "ros/ros.h"
#include "std_msgs/String.h"

void chatterCallback(const std_msgs::String::ConstPtr& msg)
{
  ROS_INFO("I heard: [%s]", msg->data.c_str());
}

int main(int argc, char **argv)
{
  ros::init(argc, argv, "listener");

  ros::NodeHandle n;

  ros::Subscriber sub = n.subscribe("chatter", 1000, chatterCallback);
  
  ros::spin();

  return 0;
}

好了，把上面的源文件放到mypackage1/src下就可以了。

接下來，要告訴編譯器如何去找到這兩個文件。你需要打開mypackage1/CMakeLists.txt，在文件的末尾添加兩行命令：

rosbuild_add_executable(talker src/talker.cpp)
rosbuild_add_executable(listener src/listener.cpp)

 添加后的文件結構是這樣的：

cmake_minimum_required(VERSION 2.4.6)
include($ENV{ROS_ROOT}/core/rosbuild/rosbuild.cmake)

# Set the build type.  Options are:
#  Coverage       : w/ debug symbols, w/o optimization, w/ code-coverage
#  Debug          : w/ debug symbols, w/o optimization
#  Release        : w/o debug symbols, w/ optimization
#  RelWithDebInfo : w/ debug symbols, w/ optimization
#  MinSizeRel     : w/o debug symbols, w/ optimization, stripped binaries
#set(ROS_BUILD_TYPE RelWithDebInfo)

rosbuild_init()

#set the default path for built executables to the "bin" directory
set(EXECUTABLE_OUTPUT_PATH ${PROJECT_SOURCE_DIR}/bin)
#set the default path for built libraries to the "lib" directory
set(LIBRARY_OUTPUT_PATH ${PROJECT_SOURCE_DIR}/lib)

#uncomment if you have defined messages
rosbuild_genmsg()
#uncomment if you have defined services
rosbuild_gensrv()

#common commands for building c++ executables and libraries
#rosbuild_add_library(${PROJECT_NAME} src/example.cpp)
#target_link_libraries(${PROJECT_NAME} another_library)
#rosbuild_add_boost_directories()
#rosbuild_link_boost(${PROJECT_NAME} thread)
#rosbuild_add_executable(example examples/example.cpp)
#target_link_libraries(example ${PROJECT_NAME})
rosbuild_add_executable(talker src/talker.cpp)
rosbuild_add_executable(listener src/listener.cpp)

 萬事具備，這樣我們就可用rosmake命令來編譯這個mypackage1包了。執行下面的命令：

$ rosmake mypackage1

輸出下面的信息：

horsetail@horsetail-book:~$ roscore
... logging to /home/horsetail/.ros/log/6eae5b9c-628d-11e5-8bd7-3859f9722953/roslaunch-horsetail-book-6447.log
Checking log directory for disk usage. This may take awhile.
Press Ctrl-C to interrupt
Done checking log file disk usage. Usage is <1GB.

started roslaunch server http://horsetail-book:44362/
ros_comm version 1.11.13


SUMMARY
========

PARAMETERS
 * /rosdistro: jade
 * /rosversion: 1.11.13

NODES

auto-starting new master
process[master]: started with pid [6459]
ROS_MASTER_URI=http://horsetail-book:11311/

...(內容太長了，省去)
             
[ rosmake ] Results:                                                            
[ rosmake ] Built 26 packages with 0 failures.                                  
[ rosmake ] Summary output to directory                                         
[ rosmake ] /home/horsetail/.ros/rosmake/rosmake_output-20150924-164014  

哇，編譯通過，大家注意到實際上也是用catkin進行編譯的，額。我們來運行一下吧。

 

1.4、運行

首先打開一個新的終端，啟動初始化ROS，執行命令：

$ roscore

然后再打開一個新的終端，啟動talker節點，執行命令：

$ rosrun mypackage1 talker

然后再打開一個新的終端，啟動listener節點，執行命令：

$ rosrun mypackage1 listener

這個時候，可以看到listener的窗口不斷的接收到數據，如下圖所示：

[ INFO] [1443085572.809193925]: I heard:[I am the talker node]
[ INFO] [1443085572.909233411]: I heard:[I am the talker node]
[ INFO] [1443085573.009267370]: I heard:[I am the talker node]
[ INFO] [1443085573.109118292]: I heard:[I am the talker node]
[ INFO] [1443085573.209204095]: I heard:[I am the talker node]
[ INFO] [1443085573.309314244]: I heard:[I am the talker node]
[ INFO] [1443085573.409269818]: I heard:[I am the talker node]
[ INFO] [1443085573.509309147]: I heard:[I am the talker node]

這說明talker廣播的消息是能夠被listener接收到的，因此程序可以正常運行了。好了，至此基於rosmake的編譯和運行完成了。

 

1.5、源碼

最后，附上源碼：dev.tar.gz

 

2、catkin_make編譯包package

catkin命令創建工作空間和包相對要復雜些，但是熟悉以后對項目的管理是非常有利的，因此官方也建議使用第二種方式。

 

2.1、創建工作空間

在開始具體工作之前，首先創建工作空間，並且為工作空間設置環境變量到~/.bashrc中，如果要查看已有的空間路徑，可以用查詢命令

$ echo $ROS_PACKAGE_PATH

你將會看到如下的信息：

/home/horsetail/dev/rosbook:/home/horsetail/catkin_ws/src:/opt/ros/jade/share:/opt/ros/jade/stacks

這里的創建空間實際上就是先建立一個文件夾，然后把文件夾的路徑設置到環境變量~/.bashrc中。例如我們這里創建目錄~/dev/rosbook作為工作空間，和第一種方法類似。

下面我們開始創建一個catkin 工作空間：

$ mkdir -p ~/catkin_ws/src
$ cd ~/catkin_ws/src

即使這個工作空間是空的（在'src'目錄中沒有任何軟件包，只有一個CMakeLists.txt鏈接文件），你依然可以“build”它：

$ cd ~/catkin_ws/ 
$ catkin_make

接下來首先source一下新生成的setup.*sh文件，把它加入環境變量到~/.bashrc文件中：

$ source ~/catkin_ws/devel/setup.bash

到此你的工作空間環境已經搭建完成

 

2.2、創建包

 首先切換到之前創建的catkin工作空間中的src目錄下：

 $ cd ~/catkin_ws/src

現在使用catkin_create_pkg命令來創建一個名為'mypackage1'的新程序包，這個程序包依賴於std_msgs、roscpp和rospy：

 $ catkin_create_pkg mypackage1 std_msgs rospy roscpp

這將會創建一個名為beginner_tutorials的文件夾，這個文件夾里面包含一個package.xml文件和一個CMakeLists.txt文件，這兩個文件都已經自動包含了部分你在執行catkin_create_pkg命令時提供的信息。

和第一種方法類似類似，把1.3節中的兩個talker.cpp和listener.cpp拷貝到mypackage1/src下。

接下來，要告訴編譯器如何去找到這兩個文件。你需要打開mypackage1/CMakeLists.txt，在文件的末尾添加命令：

include_directories(include ${catkin_INCLUDE_DIRS})

add_executable(talker src/talker.cpp)
target_link_libraries(talker ${catkin_LIBRARIES})

add_executable(listener src/listener.cpp)
target_link_libraries(listener ${catkin_LIBRARIES})

整理后的mypackage/CMakeLists.txt內容結構如下：

cmake_minimum_required(VERSION 2.8.3)
project(mypackage1)

## Find catkin and any catkin packages
find_package(catkin REQUIRED COMPONENTS roscpp rospy std_msgs)

## Declare ROS messages and services
#add_message_files(FILES Num.msg)#默認是不注釋掉的，編譯會出錯
#add_service_files(FILES AddTwoInts.srv)#默認是不注釋掉的，編譯會出錯

## Generate added messages and services
#generate_messages(DEPENDENCIES std_msgs)#默認是不注釋掉的，編譯會出錯

## Declare a catkin package
catkin_package()

## Build talker and listener
include_directories(include ${catkin_INCLUDE_DIRS})

add_executable(talker src/talker.cpp)
target_link_libraries(talker ${catkin_LIBRARIES})
add_dependencies(talker beginner_tutorials_generate_messages_cpp)

add_executable(listener src/listener.cpp)
target_link_libraries(listener ${catkin_LIBRARIES})
add_dependencies(listener beginner_tutorials_generate_messages_cpp)

注意：CMakeLists.txt中的有三那個命令是保留的:

## Declare ROS messages and services
#add_message_files(FILES Num.msg)
#add_service_files(FILES AddTwoInts.srv)

## Generate added messages and services
#generate_messages(DEPENDENCIES std_msgs)

這是關於服務消息方面的，這個項目中並沒有用到，因此必須要注釋掉，否則編譯會出現錯誤如下：

Base path: /home/horsetail/catkin_ws
Source space: /home/horsetail/catkin_ws/src
Build space: /home/horsetail/catkin_ws/build
Devel space: /home/horsetail/catkin_ws/devel
Install space: /home/horsetail/catkin_ws/install
####
#### Running command: "make cmake_check_build_system" in "/home/horsetail/catkin_ws/build"
####
-- Using CATKIN_DEVEL_PREFIX: /home/horsetail/catkin_ws/devel
-- Using CMAKE_PREFIX_PATH: /home/horsetail/catkin_ws/devel;/opt/ros/jade
-- This workspace overlays: /home/horsetail/catkin_ws/devel;/opt/ros/jade
-- Using PYTHON_EXECUTABLE: /usr/bin/python
-- Using Debian Python package layout
-- Using empy: /usr/bin/empy
-- Using CATKIN_ENABLE_TESTING: ON
-- Call enable_testing()
-- Using CATKIN_TEST_RESULTS_DIR: /home/horsetail/catkin_ws/build/test_results
-- Found gtest sources under '/usr/src/gtest': gtests will be built
-- Using Python nosetests: /usr/bin/nosetests-2.7
-- catkin 0.6.14
-- BUILD_SHARED_LIBS is on
-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-- ~~  traversing 1 packages in topological order:
-- ~~  - mypackage1
-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-- +++ processing catkin package: 'mypackage1'
-- ==> add_subdirectory(mypackage1)
CMake Error at mypackage1/CMakeLists.txt:8 (add_message_files):
  Unknown CMake command "add_message_files".


-- Configuring incomplete, errors occurred!
See also "/home/horsetail/catkin_ws/build/CMakeFiles/CMakeOutput.log".
See also "/home/horsetail/catkin_ws/build/CMakeFiles/CMakeError.log".
make: *** [cmake_check_build_system] 錯誤 1

這個錯誤也折騰了我一陣子，以此銘記之。

好了，接下來就是編譯它了。

 

2.3、編譯

 catkin_make 是一個命令行工具，它簡化了catkin的標准工作流程。你可以認為catkin_make是在CMake標准工作流程中依次調用了cmake 和 make。

使用方法:

# 在catkin工作空間下

$ catkin_make [make_targets] [-DCMAKE_VARIABLES=...]

記得事先source你的環境配置(setup)文件，在Ubuntu中的操作指令如下：

 $ source /opt/ros/indigo/setup.bash

切換到catkin workspace ：

 $ cd ~/catkin_ws/

執行編譯:

 $ catkin_make

輸出如下編譯信息：

Base path: /home/horsetail/catkin_ws
Source space: /home/horsetail/catkin_ws/src
Build space: /home/horsetail/catkin_ws/build
Devel space: /home/horsetail/catkin_ws/devel
Install space: /home/horsetail/catkin_ws/install
####
#### Running command: "make cmake_check_build_system" in "/home/horsetail/catkin_ws/build"
####
-- Using CATKIN_DEVEL_PREFIX: /home/horsetail/catkin_ws/devel
-- Using CMAKE_PREFIX_PATH: /home/horsetail/catkin_ws/devel;/opt/ros/jade
-- This workspace overlays: /home/horsetail/catkin_ws/devel;/opt/ros/jade
-- Using PYTHON_EXECUTABLE: /usr/bin/python
-- Using Debian Python package layout
-- Using empy: /usr/bin/empy
-- Using CATKIN_ENABLE_TESTING: ON
-- Call enable_testing()
-- Using CATKIN_TEST_RESULTS_DIR: /home/horsetail/catkin_ws/build/test_results
-- Found gtest sources under '/usr/src/gtest': gtests will be built
-- Using Python nosetests: /usr/bin/nosetests-2.7
-- catkin 0.6.14
-- BUILD_SHARED_LIBS is on
-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-- ~~  traversing 1 packages in topological order:
-- ~~  - mypackage1
-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-- +++ processing catkin package: 'mypackage1'
-- ==> add_subdirectory(mypackage1)
-- Configuring done
-- Generating done
-- Build files have been written to: /home/horsetail/catkin_ws/build
####
#### Running command: "make -j4 -l4" in "/home/horsetail/catkin_ws/build"
####
Scanning dependencies of target talker
Scanning dependencies of target listener
[ 50%] Building CXX object mypackage1/CMakeFiles/listener.dir/src/listener.cpp.o
[100%] Building CXX object mypackage1/CMakeFiles/talker.dir/src/talker.cpp.o
Linking CXX executable /home/horsetail/catkin_ws/devel/lib/mypackage1/talker
[100%] Built target talker
Linking CXX executable /home/horsetail/catkin_ws/devel/lib/mypackage1/listener
[100%] Built target listener

恭喜編譯成功了，接下來可以嘗下先。

 

2.4、運行

運行的步驟和1.3是一樣的，請參閱1.3的詳細描述。因為按照兩種方法編譯了兩個相同的包名和節點，因此在啟動時會提示選擇哪一個節點進行運行，按照提示選擇即可。

 

2.5、源碼

最后，附上源碼：catkin_ws.tar.gz

 

參考資料

[1]. Aaron Martinez Enrique Fern andez, ROS機器人程序設計[B], P14-42, 2014.