Publish radar ros message repeated detected objects.

edit

Hi, I have a radar sensor to detect vehicles in front of the car. each detected object has its data in the form of

struct
{
   int32 ObjectID;
   float32 distance;
   float32 velocity;
   float32 zimuth ;
   float32 elevation;
} Radar_Point

I want to push this radar data using a standard ROS message I found the message

radar_msgs/msg/RadarScan.msg

std_msgs/Header header
radar_msgs/RadarReturn[] returns

and

radar_msgs/msg/RadarReturn.msg

# All variables below are relative to the radar's frame of reference.
# This message is not meant to be used alone but as part of a stamped or array message.

float32 range                            # Distance (m) from the sensor to the detected return.
float32 azimuth                          # Angle (in radians) in the azimuth plane between the sensor and the detected return.
                                         #    Positive angles are anticlockwise from the sensor and negative angles clockwise from the sensor as per REP-0103.
float32 elevation                        # Angle (in radians) in the elevation plane between the sensor and the detected return.
                                         #    Negative angles are below the sensor. For 2D radar, this will be 0.
float32 doppler_velocity                 # The doppler speeds (m/s) of the return.
float32 amplitude                        # The amplitude of the of the return (dB)

I find it difficult to map the radar sensor data to the radar ros message before I can publish it.

radar_msgs::RadarScan msgRadarScan;

ros::init(argc, argv, "conti_radar"); ros::NodeHandle n; ros::Publisher publisher_contiradar = n.advertise <radar_msgs::radarscan>("/conti_radar", 100);

void handledata( const double & simTime, const unsigned int & simFrame, std::vector<Radar_Point> & item, bool isExtended )
{
    for (auto i = item.begin(); i != item.end(); ++i)
    {
        msgRadarScan.header.stamp.sec = simTime;
        msgRadarScan.header.stamp.nsec = (simTime - msgRadarScan.header.stamp.sec)*1000000000;
        msgRadarScan.header.frame_id = "base_link";
        msgRadarScan.returns.range =  item[i].distance;
        msgRadarScan.returns.velocity =  item[i].doppler_velocity;
        msgRadarScan.returns.zimuth =  item[i].azimuth;
        msgRadarScan.returns.elevation =  item[i].elevation;
        msgRadarScan.returns.push_back();
    }
}

publisher_contiradar.publish(msgRadarScan);

I try to implement in this way because For the radar sensor data, I have a number of detected objects. So I am thinking about adding a newly detected object to an array or vector?. Certainly, my code is wrong with many errors I just want to give you an idea about my idea. Can anyone help me to review the message conversion part? there must be a better way to publish Radar data to the ROS server. Please give me some suggestion