下面使用SYD Dynamics的9軸AHRS(Attitude and heading reference system)，來發布sensor_msgs/Imu類型的消息。

　　將傳感器用USB轉串口接到Ubuntu系統上，可以用如下命令查看串口信息：

ls -l /dev/tty*

　　查詢出串口名為“/dev/ttyUSB0”。根據官方給的傳感器程序源文件和boost::asio庫來實現串口發送request指令，並讀取傳感器返回的四元數信息。之後將其發送到/IMU_data的話題上：

// Step 1:  Include Library Headers:
#include "EasyObjectDictionary.h
 
"
#include "EasyProfile.h"

#include <ros/ros.h> 
#include <sensor_msgs/Imu.h>

#include <boost/asio.hpp>         // 包含boost庫函數
#include <boost/bind.hpp>
using namespace boost::asio;  


int main(int argc, char** argv)
{
    // Step 2: Initialization:
    EasyProfile_C_Interface_Init();

    ros::init(argc, argv, 
 
"imu");     
    ros::NodeHandle n;  

    ros::Publisher IMU_pub = n.advertise<sensor_msgs::Imu>("IMU_data", 20);  

    io_service io;
    serial_port sp(io, "/dev/ttyUSB0");         // 定義傳輸的串口
    sp.set_option(serial_port::baud_rate(115200));                                  // 波特率
    sp.set_option(  serial_port::flow_control( serial_port::flow_control::none ) ); 
 
// 流量控制
    sp.set_option(  serial_port::parity( serial_port::parity::none ) );             // 奇偶校驗
    sp.set_option( serial_port::stop_bits(  serial_port::stop_bits::one ) );        // 停止位
    sp.set_option(  serial_port::character_size( 8 ) );                             // 數據位

    ros::Rate loop_rate(50);  
    while(ros::ok())
    {
        // Step 3 and Step 4 are optional, only if you want to use the request-response communication pattern
        // Step 3: Request quaternion Data from TransdcuerM 
        uint16 toId = 309; // Node ID
        char*  txData;
        int    txSize;
        if(EP_SUCC_ == EasyProfile_C_Interface_TX_Request(toId, EP_CMD_Q_S1_E_, &txData, &txSize))
        {
            write(sp, buffer(txData, txSize));    // Step 4:  Send the request via Serial Port.
        } 

        char rxData[100];  
        boost::system::error_code err;  

        sp.read_some(buffer(rxData, 50),err);  // Read from serial port buffer
        if (err)  
        {  
            ROS_INFO("Serial port read_some Error!");  
            return -1;  
        }  

        Ep_Header header;                       // Then let the EasyProfile do the rest such as data assembling and checksum verification.
        if( EP_SUCC_ == EasyProfile_C_Interface_RX((char*)rxData, 50, &header))
        {
            // Quanternion received
            unsigned int timeStamp = ep_Q_s1_e.timeStamp;
            float q1 = ep_Q_s1_e.q[0];              // Note 1, ep_Q_s1_e is defined in the EasyProfile library as a global variable
            float q2 = ep_Q_s1_e.q[1];              // Note 2, for the units and meaning of each value, refer to EasyObjectDictionary.h
            float q3 = ep_Q_s1_e.q[2];
            float q4 = ep_Q_s1_e.q[3];
            ROS_INFO("Q: %f %f %f %f\n", q1, q2, q3, q4);

            sensor_msgs::Imu imu_data;
            imu_data.header.stamp = ros::Time::now();
            imu_data.header.frame_id = "base_link";
            imu_data.orientation.x = q3;
            imu_data.orientation.y = -q2;
            imu_data.orientation.z = -q1;
            imu_data.orientation.w = q4;

            IMU_pub.publish(imu_data);
        }

        io.run();  
        ros::spinOnce();  
        loop_rate.sleep();  
    }

    return 0;
}

　　在CMakeLists中添加：

add_compile_options(-std=c99)

aux_source_directory(./src  DIR_SRCS)
add_executable(imu   ${DIR_SRCS} )
target_link_libraries(imu  ${catkin_LIBRARIES})

　　使用catkin_make編譯後，source ./devel/setup.bash，然後運行rosrun imu imu。這時可能會出現無法打開串口的錯誤，給串口添加權限後再次運行：

sudo chmod 666 /dev/ttyUSB0

　　無問題後可以輸入下面的指令查看話題，轉動IMU可以看到orientation的四個分量一直在變化：

rostopic  echo  /IMU_data

　　為了更形象的顯示IMU姿態，可以下載rviz_imu_plugin插件並安裝。The rviz_imu_plugin package is used to display sensor_msgs/Imu messages in rviz. Once you download and compile the package, it should be visible as a plugin. It displays the orientation of the IMU using a box as well as and coordinate axes. The acceleration can be visualized using a vector.

　　Make sure you have git installed:

sudo apt-get install git-core

　　Download the stack from our repository into your catkin workspace

git clone -b indigo https://github.com/ccny-ros-pkg/imu_tools.git

　　Compile the stack:

cd ~/catkin_ws
catkin_make

　　裝好後打開rviz，可以看到rviz_imu_plugin與rviz中默認自帶的rviz_plugin_tutorials並不一樣：

　　在rviz_imu_plugin下添加imu，修改Fixed Frame為base_link，IMU下面的Topic選為/IMU_data，轉動IMU rviz中的虛擬立方體和坐標軸會跟著轉動（可以更改box三個方向尺寸的比例）：

參考：

IMU tools for ROS

CMake 入門實戰

ROS Qt Creator Plug-in wiki

ROS下IMU串口通訊接口（通用版）

如何使用Qt插件在Qt中進行ROS開發

如何用Qt對ROS項目進行調試及創建GUI界面

Serial Cross-platform, Serial Port library written in C++

ROS中使用IMU傳感器發布消息