ROS melodic 串口通信

topic_serial_node.cpp

// topic_serial_node.cpp
// serial API: http://wjwwood.io/serial/doc/1.1.0/index.html
// serial install: sudo apt install ros-melodic-serial

#include <ros/ros.h>
#include <serial/serial.h> //ROS已經內置了的串口包
#include <std_msgs/String.h>
#include <std_msgs/Empty.h>

serial::Serial ser; //聲明串口對象

//回調函數
void topic_read_callback(const std_msgs::String::ConstPtr &msg)
{
    ROS_INFO_STREAM("topic_serial_read:" << msg->data);
    //ser.write(msg->data); //發送串口數據，有了控制檯，所以把串口打印關了
}

int main(int argc, char **argv)
{
    //初始化節點
    ros::init(argc, argv, "topic_serial_node");
    //聲明節點句柄
    ros::NodeHandle nh;

    //訂閱主題，並配置回調函數
    ros::Subscriber read_sub = nh.subscribe("topic_serial_read", 1000, topic_read_callback);
    //發佈主題
    ros::Publisher write_pub = nh.advertise<std_msgs::String>("topic_serial_write", 1000);

    try
    {
        //設置串口屬性，並打開串口
        ser.setPort("/dev/ttyUSB0");    // 此處要注串口設備權限，見下文
        ser.setBaudrate(115200);
        serial::Timeout to = serial::Timeout::simpleTimeout(1000);
        ser.setTimeout(to);
        ser.open();
    }
    catch (serial::IOException &e)
    {
        std::string err = e.what();
        ROS_ERROR_STREAM(err);
        ROS_ERROR_STREAM("Unable to open port ");
        return -1;
    }

    //檢測串口是否已經打開，並給出提示信息
    if (ser.isOpen())
    {
        ROS_INFO_STREAM("Serial Port initialized");
    }
    else
    {
        return -1;
    }

    //指定循環的頻率
    ros::Rate loop_rate(50);
    while (ros::ok())
    {
        if (ser.available())
        {
            //ROS_INFO_STREAM("Reading from serial port\n");
            std_msgs::String result;
            result.data = ser.read(ser.available());
            ROS_INFO_STREAM("Read: " << result.data);
            write_pub.publish(result);
        }

        //處理ROS的信息，比如訂閱消息,並調用回調函數
        ros::spinOnce();
        loop_rate.sleep();
    }
}

launch:

<launch>
<node pkg="topic_serial" type="topic_serial_node" name="topic_serial_node"  output="screen"/>
</launch>

CMakefile.txt

cmake_minimum_required(VERSION 2.8.3)
project(topic_serial)

## Compile as C++11, supported in ROS Kinetic and newer
# add_compile_options(-std=c++11)

## 這是進行catkin構建時所需的組件包。
## 依賴包是message_generation、 std_msgs和roscpp。如果這些包不存在，在構建過程中會發生錯誤。
find_package(catkin REQUIRED 
        COMPONENTS 
        message_generation 
        std_msgs 
        roscpp
        serial
)

## System dependencies are found with CMake's conventions
# find_package(Boost REQUIRED COMPONENTS system)

# catkin_python_setup()

################################################
## Declare ROS messages, services and actions ##
################################################


###################################
## catkin specific configuration ##
###################################

catkin_package(
  #INCLUDE_DIRS include
  LIBRARIES   
  CATKIN_DEPENDS 
  std_msgs
  roscpp     
)

###########
## Build ##
###########

## Specify additional locations of header files
## Your package locations should be listed before other locations
include_directories(
  include 
  ${catkin_INCLUDE_DIRS}
)

add_executable(topic_serial_node
        src/topic_serial_node.cpp
)
add_dependencies(topic_serial_node  
        ${${PROJECT_NAME}_EXPORTED_TARGETS} 
        ${catkin_EXPORTED_TARGETS}
        serial
)
target_link_libraries(topic_serial_node
        ${catkin_LIBRARIES}
)

Linux/ROS——獲取串口權限

此處參考：https://blog.csdn.net/weixin_30258027/article/details/97362051

創建ttyUSB權限規則文件etc/udev/rules.d/70-ttyUSB.rules

$ sudo nano -p /etc/udev/rules.d/70-ttyUSB.rules

在70-ttyUSB.rules文件中寫入下列代碼：

KERNEL=="ttyUSB*", OWNER="root", GROUP="root", MODE="0666" 

保存即可,重啓或註銷用戶在登錄後生效