ROS2 (1): 创建工作空间及创建python节点

ROS2 (1): 创建工作空间及创建python节点 1. 创建工作空间

mkdir -p 02_ros_ws/src

进入terminal，查看文件夹

2. 创建功能包

ros2 pkg create tom --build-type ament_python --dependencies rclpy

cd 进入src文件夹后，执行上述命令。其中 ros2 pkg create --build-type --dependencies 如中括号中填写内容，若使用C++进行编写，type和dependencies是不一样的。

cd 进入工作空间，可以看到

 使用tree命令，得到如下文件结构

3. 编写python节点代码

import rclpy
from rclpy.node import Node

def main(args=None):
    # init the client lib
    rclpy.init(args=args)
    # create node instance
    node_tom_say = Node(node_name="tom_say")
    # get logger
    node_tom_say.get_logger().info("Hello, Jerry. I am comming.")
    # spin the node
    rclpy.spin(node=node_tom_say)
    # shutdown the node
    rclpy.shutdown()

4. 修改配置文件

打开配置文件，src/tom/setup.py

from setuptools import setup

package_name = 'tom'

setup(
    name=package_name,
    version='0.0.0',
    packages=[package_name],
    data_files=[
        ('share/ament_index/resource_index/packages',
            ['resource/' + package_name]),
        ('share/' + package_name, ['package.xml']),
    ],
    install_requires=['setuptools'],
    zip_safe=True,
    maintainer='franklin',
    maintainer_email='franklin@todo.todo',
    description='TODO: Package description',
    license='TODO: License declaration',
    tests_require=['pytest'],
    entry_points={
        'console_scripts': [
        ],
    },
)

在 entry_points={'console_scripts': [],}中添加节点位置，修改后如下所示

from setuptools import setup

package_name = 'tom'

setup(
    name=package_name,
    version='0.0.0',
    packages=[package_name],
    data_files=[
        ('share/ament_index/resource_index/packages',
            ['resource/' + package_name]),
        ('share/' + package_name, ['package.xml']),
    ],
    install_requires=['setuptools'],
    zip_safe=True,
    maintainer='franklin',
    maintainer_email='franklin@todo.todo',
    description='TODO: Package description',
    license='TODO: License declaration',
    tests_require=['pytest'],
    entry_points={
        'console_scripts': [
            "node_tom_say=tom.tom_say:main"
        ],
    },
)

5. 编译节点

cd 02_ros_ws, 编译节点 colcon build ,编译后如下如所示

source 更新一下

source install/setup.bash

查看功能包是否存在

ros2 pkg list | grep tom

查看如下信息

 6. 运行节点

 查看节点

 

 7. 代码优化

import rclpy
from rclpy.node import Node

class TomNode(Node):

    def __init__(self, name):
        super().__init__(name)
        self.get_logger().info(f"Hello, Jerry. {name} is comming again.")

def main(args=None):
    # init the client lib
    rclpy.init(args=args)
    # create node instance
    node_tom_say_again = TomNode(name="tom_say_again")
    # spin the node
    rclpy.spin(node=node_tom_say_again)
    # shutdown the node
    rclpy.shutdown()

修改配置文件setup.py. 添加 "node_tom_say_again=tom.tom_say_code_updated:main"

from setuptools import setup

package_name = 'tom'

setup(
    name=package_name,
    version='0.0.0',
    packages=[package_name],
    data_files=[
        ('share/ament_index/resource_index/packages',
            ['resource/' + package_name]),
        ('share/' + package_name, ['package.xml']),
    ],
    install_requires=['setuptools'],
    zip_safe=True,
    maintainer='franklin',
    maintainer_email='franklin@todo.todo',
    description='TODO: Package description',
    license='TODO: License declaration',
    tests_require=['pytest'],
    entry_points={
        'console_scripts': [
            "node_tom_say=tom.tom_say:main",
            "node_tom_say_again=tom.tom_say_code_updated:main"
        ],
    },
)

重新编译：

 

参考连接：

【鱼香ROS】动手学ROS2|ROS2基础入门到实践教程|小鱼带你手把手学习ROS2_哔哩哔哩_bilibili