ros2使用launch动态传参

头文件

首先ROS2launch使用Python编写

必要的头文件

import os
import launch

from launch import LaunchDescription
from launch.actions import DeclareLaunchArgument
from launch.substitutions import LaunchConfiguration
from launch_ros.actions import Node

launch参数

def generate_launch_description():
    correct_factor_vx_arg = DeclareLaunchArgument('correct_factor_vx', default_value='0.898',
                                         description='correct factor vx, e.g. 0.9')

加上参数服务器传参

def generate_launch_description():
    correct_factor_vx_arg = DeclareLaunchArgument('correct_factor_vx', default_value='0.898',
                                         description='correct factor vx, e.g. 0.9')

    # 添加以下  
    originbot_base_node = Node(
            package='originbot_base',
            executable='originbot_base', 
            output='screen',
            emulate_tty=True,
            parameters=[{
                    'correct_factor_vx': LaunchConfiguration('correct_factor_vx'), 
            }])

return这些参数和执行文件

def generate_launch_description():
    correct_factor_vx_arg = DeclareLaunchArgument('correct_factor_vx', default_value='0.898',
                                         description='correct factor vx, e.g. 0.9')

    originbot_base_node = Node(
            package='originbot_base',
            executable='originbot_base', 
            output='screen',
            emulate_tty=True,
            parameters=[{
                    'correct_factor_vx': LaunchConfiguration('correct_factor_vx'), 
            }])

    # 添加以下        
    return LaunchDescription([
            correct_factor_vx_arg,
            originbot_base_node,
        ])

命令行传参

$ ros2 launch  learning_launch parameters.launch.py correct_factor_vx_arg:=0.777

示例

执行文件(c++)

foxy中如下：

float correct_factor_vx_ = 1.0;
this->declare_parameter("correct_factor_vx");   //声明及获取线速度校正参数
this->get_parameter_or<float>("correct_factor_vx", correct_factor_vx_, 1.0);

humble如下：

float correct_factor_vx_ = this->declare_parameter("correct_factor_vx", 1.0);