ROS2 之 使用 parameters

#include <rclcpp/rclcpp.hpp>
#include <chrono>
#include <string>
#include <functional>

using namespace std::chrono_literals;

class ParametersClass: public rclcpp::Node
{
  public:
    ParametersClass()
      : Node("parameter_node")
    {
      this->declare_parameter<std::string>("my_parameter", "world");
      timer_ = this->create_wall_timer(
      1000ms, std::bind(&ParametersClass::respond, this));
    }
    void respond()
    {
      this->get_parameter("my_parameter", parameter_string_);
      RCLCPP_INFO(this->get_logger(), "Hello %s", parameter_string_.c_str());
    }
  private:
    std::string parameter_string_;
    rclcpp::TimerBase::SharedPtr timer_;
};

int main(int argc, char** argv)
{
  rclcpp::init(argc, argv);
  rclcpp::spin(std::make_shared<ParametersClass>());
  rclcpp::shutdown();
  return 0;
}

编译执行后, 每秒出现一次  

[INFO] [parameter_node]: Hello world

在控制台手动改写参数

	
	

	

		
		
首先确保
ros2 run cpp_parameters parameter_node 已经运行

ros2 param list
ros2 param set /parameter_node 参数名 参数值

	



 
通过 launch文件修改参数

 

	
	

	

		
		
from launch import LaunchDescription
from launch_ros.actions import Node

def generate_launch_description():
    return LaunchDescription([
        Node(
            package="cpp_parameters",
            executable="parameter_node",
            name="custom_parameter_node",
            output="screen",
            emulate_tty=True,
            parameters=[
                {"my_parameter": "earth"}
            ]
        )
    ])