mrpt_ekf_slam_2d_wrapper.cpp

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/*
 * File: mrpt_ekf_slam_2d_wrapper.cpp
 * Author: Vladislav Tananaev
 *
 */

#include "mrpt_ekf_slam_2d/mrpt_ekf_slam_2d_wrapper.h"

EKFslamWrapper::EKFslamWrapper()
{
  rawlog_play_ = false;
  mrpt_bridge::convert(ros::Time(0), timeLastUpdate_);
}
EKFslamWrapper::~EKFslamWrapper()
{
}
bool EKFslamWrapper::is_file_exists(const std::string& name)
{
  std::ifstream f(name.c_str());
  return f.good();
}

void EKFslamWrapper::get_param()
{
  ROS_INFO("READ PARAM FROM LAUNCH FILE");
  n_.param<double>("ellipse_scale", ellipse_scale_, 1);
  ROS_INFO("ellipse_scale: %f", ellipse_scale_);

  n_.param<double>("rawlog_play_delay", rawlog_play_delay, 0.1);
  ROS_INFO("rawlog_play_delay: %f", rawlog_play_delay);

  n_.getParam("rawlog_filename", rawlog_filename);
  ROS_INFO("rawlog_filename: %s", rawlog_filename.c_str());

  n_.getParam("ini_filename", ini_filename);
  ROS_INFO("ini_filename: %s", ini_filename.c_str());

  n_.param<std::string>("global_frame_id", global_frame_id, "map");
  ROS_INFO("global_frame_id: %s", global_frame_id.c_str());

  n_.param<std::string>("odom_frame_id", odom_frame_id, "odom");
  ROS_INFO("odom_frame_id: %s", odom_frame_id.c_str());

  n_.param<std::string>("base_frame_id", base_frame_id, "base_link");
  ROS_INFO("base_frame_id: %s", base_frame_id.c_str());

  n_.param<std::string>("sensor_source", sensor_source, "scan");
  ROS_INFO("sensor_source: %s", sensor_source.c_str());
}
void EKFslamWrapper::init()
{
  // get parameters from ini file

  if (!is_file_exists(ini_filename))
  {
    ROS_ERROR_STREAM("CAN'T READ INI FILE");
    return;
  }

  EKFslam::read_iniFile(ini_filename);
  // read rawlog file if it  exists
  if (is_file_exists(rawlog_filename))
  {
    ROS_WARN_STREAM("PLAY FROM RAWLOG FILE: " << rawlog_filename.c_str());
    rawlog_play_ = true;
  }

  state_viz_pub_ = n_.advertise<visualization_msgs::MarkerArray>("/state_viz", 1);  // map
  data_association_viz_pub_ =
      n_.advertise<visualization_msgs::MarkerArray>("/data_association_viz", 1);  // data_association

  // read sensor topics
  std::vector<std::string> lstSources;
  mrpt::system::tokenize(sensor_source, " ,\t\n", lstSources);
  ROS_ASSERT_MSG(!lstSources.empty(), "*Fatal*: At least one sensor source must be provided in ~sensor_sources (e.g. "
                                      "\"scan\" or \"beacon\")");

  sensorSub_.resize(lstSources.size());
  for (size_t i = 0; i < lstSources.size(); i++)
  {
    if (lstSources[i].find("landmark") != std::string::npos)
    {
      sensorSub_[i] = n_.subscribe(lstSources[i], 1, &EKFslamWrapper::landmarkCallback, this);
    }
    else
    {
      ROS_ERROR("Can't find the sensor topics. The sensor topics should contain the word \"landmark\" in the name");
    }
  }

  init3Dwindow();
}

void EKFslamWrapper::odometryForCallback(CObservationOdometryPtr& _odometry, const std_msgs::Header& _msg_header)
{
  mrpt::poses::CPose3D poseOdom;
  if (this->waitForTransform(poseOdom, odom_frame_id, base_frame_id, _msg_header.stamp, ros::Duration(1)))
  {
    _odometry = CObservationOdometry::Create();
    _odometry->sensorLabel = odom_frame_id;
    _odometry->hasEncodersInfo = false;
    _odometry->hasVelocities = false;
    _odometry->odometry.x() = poseOdom.x();
    _odometry->odometry.y() = poseOdom.y();
    _odometry->odometry.phi() = poseOdom.yaw();
  }
}

void EKFslamWrapper::updateSensorPose(std::string _frame_id)
{
  CPose3D pose;
  tf::StampedTransform transform;
  try
  {
    listenerTF_.lookupTransform(base_frame_id, _frame_id, ros::Time(0), transform);

    tf::Vector3 translation = transform.getOrigin();
    tf::Quaternion quat = transform.getRotation();
    pose.x() = translation.x();
    pose.y() = translation.y();
    pose.z() = translation.z();
    double roll, pitch, yaw;
    tf::Matrix3x3 Rsrc(quat);
    CMatrixDouble33 Rdes;
    for (int c = 0; c < 3; c++)
      for (int r = 0; r < 3; r++)
        Rdes(r, c) = Rsrc.getRow(r)[c];
    pose.setRotationMatrix(Rdes);
    landmark_poses_[_frame_id] = pose;
  }
  catch (tf::TransformException ex)
  {
    ROS_ERROR("%s", ex.what());
    ros::Duration(1.0).sleep();
  }
}

bool EKFslamWrapper::waitForTransform(mrpt::poses::CPose3D& des, const std::string& target_frame,
                                      const std::string& source_frame, const ros::Time& time,
                                      const ros::Duration& timeout, const ros::Duration& polling_sleep_duration)
{
  tf::StampedTransform transform;
  try
  {
    listenerTF_.waitForTransform(target_frame, source_frame, time, polling_sleep_duration);
    listenerTF_.lookupTransform(target_frame, source_frame, time, transform);
  }
  catch (tf::TransformException)
  {
    ROS_INFO("Failed to get transform target_frame (%s) to source_frame (%s)", target_frame.c_str(),
             source_frame.c_str());
    return false;
  }
  mrpt_bridge::convert(transform, des);
  return true;
}

void EKFslamWrapper::landmarkCallback(const mrpt_msgs::ObservationRangeBearing& _msg)
{
#if MRPT_VERSION >= 0x130
  using namespace mrpt::maps;
  using namespace mrpt::obs;
#else
  using namespace mrpt::slam;
#endif
  CObservationBearingRangePtr landmark = CObservationBearingRange::Create();

  if (landmark_poses_.find(_msg.header.frame_id) == landmark_poses_.end())
  {
    updateSensorPose(_msg.header.frame_id);
  }
  else
  {
    mrpt::poses::CPose3D pose = landmark_poses_[_msg.header.frame_id];
    mrpt_bridge::convert(_msg, landmark_poses_[_msg.header.frame_id], *landmark);

    sf = CSensoryFrame::Create();
    CObservationOdometryPtr odometry;
    odometryForCallback(odometry, _msg.header);

    CObservationPtr obs = CObservationPtr(landmark);
    sf->insert(obs);
    observation(sf, odometry);
    timeLastUpdate_ = sf->getObservationByIndex(0)->timestamp;

    tictac.Tic();
    mapping.processActionObservation(action, sf);
    t_exec = tictac.Tac();
    ROS_INFO("Map building executed in %.03fms", 1000.0f * t_exec);
    ros::Duration(rawlog_play_delay).sleep();
    mapping.getCurrentState(robotPose_, LMs_, LM_IDs_, fullState_, fullCov_);
    viz_state();
    viz_dataAssociation();
    run3Dwindow();
    publishTF();
  }
}

bool EKFslamWrapper::rawlogPlay()
{
  if (rawlog_play_ == false)
  {
    return false;
  }
  else
  {
    size_t rawlogEntry = 0;
    CFileGZInputStream rawlogFile(rawlog_filename);
    CActionCollectionPtr action;
    CSensoryFramePtr observations;

    for (;;)
    {
      if (ros::ok())
      {
        if (!CRawlog::readActionObservationPair(rawlogFile, action, observations, rawlogEntry))
        {
          break;  // file EOF
        }
        tictac.Tic();
        mapping.processActionObservation(action, observations);
        t_exec = tictac.Tac();
        ROS_INFO("Map building executed in %.03fms", 1000.0f * t_exec);
        ros::Duration(rawlog_play_delay).sleep();
        mapping.getCurrentState(robotPose_, LMs_, LM_IDs_, fullState_, fullCov_);

        viz_state();
        viz_dataAssociation();
        run3Dwindow();
      }
    }
    if (win3d)
    {
      cout << "\n Close the 3D window to quit the application.\n";
      win3d->waitForKey();
    }
    return true;
  }
}

// Local function to force the axis to be right handed for 2D. Based on the one from ecl_statistics
void EKFslamWrapper::makeRightHanded(Eigen::Matrix2d& eigenvectors, Eigen::Vector2d& eigenvalues)
{
  // Note that sorting of eigenvalues may end up with left-hand coordinate system.
  // So here we correctly sort it so that it does end up being righ-handed and normalised.
  Eigen::Vector3d c0;
  c0.setZero();
  c0.head<2>() = eigenvectors.col(0);
  c0.normalize();
  Eigen::Vector3d c1;
  c1.setZero();
  c1.head<2>() = eigenvectors.col(1);
  c1.normalize();
  Eigen::Vector3d cc = c0.cross(c1);
  if (cc[2] < 0)
  {
    eigenvectors << c1.head<2>(), c0.head<2>();
    double e = eigenvalues[0];
    eigenvalues[0] = eigenvalues[1];
    eigenvalues[1] = e;
  }
  else
  {
    eigenvectors << c0.head<2>(), c1.head<2>();
  }
}

void EKFslamWrapper::computeEllipseOrientationScale2D(tf::Quaternion& orientation, Eigen::Vector2d& scale,
                                                      const mrpt::math::CMatrixDouble covariance)
{
  tf::Matrix3x3 tf3d;
  Eigen::Vector2d eigenvalues(Eigen::Vector2d::Identity());
  Eigen::Matrix2d eigenvectors(Eigen::Matrix2d::Zero());

  // NOTE: The SelfAdjointEigenSolver only references the lower triangular part of the covariance matrix
  Eigen::SelfAdjointEigenSolver<Eigen::Matrix2d> eigensolver(covariance);
  // Compute eigenvectors and eigenvalues
  if (eigensolver.info() == Eigen::Success)
  {
    eigenvalues = eigensolver.eigenvalues();
    eigenvectors = eigensolver.eigenvectors();
  }
  else
  {
    ROS_ERROR_STREAM("failed to compute eigen vectors/values for position. Is the covariance matrix correct?");
    eigenvalues = Eigen::Vector2d::Zero();  // Setting the scale to zero will hide it on the screen
    eigenvectors = Eigen::Matrix2d::Identity();
  }

  // Be sure we have a right-handed orientation system
  makeRightHanded(eigenvectors, eigenvalues);

  // Rotation matrix around  z axis
  tf3d.setValue(eigenvectors(0, 0), eigenvectors(0, 1), 0, eigenvectors(1, 0), eigenvectors(1, 1), 0, 0, 0, 1);

  // get orientation from rotation matrix
  tf3d.getRotation(orientation);
  // get scale
  scale[0] = eigenvalues[0];
  scale[1] = eigenvalues[1];
}

void EKFslamWrapper::viz_dataAssociation()
{
  // robot pose
  mrpt::poses::CPose3D robotPose;
  robotPose = CPose3D(robotPose_.mean);
  geometry_msgs::Point pointRobotPose;
  pointRobotPose.z = 0;
  pointRobotPose.x = robotPose.x();
  pointRobotPose.y = robotPose.y();

  // visualization of the data association
  visualization_msgs::MarkerArray ma;
  visualization_msgs::Marker line_strip;

  line_strip.header.frame_id = "/map";
  line_strip.header.stamp = ros::Time::now();

  line_strip.id = 0;
  line_strip.type = visualization_msgs::Marker::LINE_STRIP;
  line_strip.action = visualization_msgs::Marker::ADD;

  line_strip.lifetime = ros::Duration(0.1);
  line_strip.pose.position.x = 0;
  line_strip.pose.position.y = 0;
  line_strip.pose.position.z = 0;
  line_strip.pose.orientation.x = 0.0;
  line_strip.pose.orientation.y = 0.0;
  line_strip.pose.orientation.z = 0.0;
  line_strip.pose.orientation.w = 1.0;
  line_strip.scale.x = 0.02;  // line uses only x component
  line_strip.scale.y = 0.0;
  line_strip.scale.z = 0.0;
  line_strip.color.a = 1.0;
  line_strip.color.r = 1.0;
  line_strip.color.g = 1.0;
  line_strip.color.b = 1.0;

  // Draw latest data association:
  const CRangeBearingKFSLAM2D::TDataAssocInfo& da = mapping.getLastDataAssociation();

  for (auto it = da.results.associations.begin(); it != da.results.associations.end(); ++it)
  {
    const prediction_index_t idxPred = it->second;
    // This index must match the internal list of features in the map:
    CRangeBearingKFSLAM2D::KFArray_FEAT featMean;
    mapping.getLandmarkMean(idxPred, featMean);

    line_strip.points.clear();
    line_strip.points.push_back(pointRobotPose);
    geometry_msgs::Point pointLm;
    pointLm.z = 0.0;
    pointLm.x = featMean[0];
    pointLm.y = featMean[1];
    line_strip.points.push_back(pointLm);
    ma.markers.push_back(line_strip);
    line_strip.id++;
  }

  data_association_viz_pub_.publish(ma);
}
void EKFslamWrapper::viz_state()
{
  visualization_msgs::MarkerArray ma;
  visualization_msgs::Marker marker;
  marker.header.frame_id = "/map";
  marker.id = 0;
  marker.type = visualization_msgs::Marker::SPHERE;
  marker.action = visualization_msgs::Marker::ADD;
  marker.lifetime = ros::Duration(0);

  // get the covariance matrix 2x2 for each ellipsoid including robot pose
  mrpt::opengl::CSetOfObjectsPtr objs;
  objs = mrpt::opengl::CSetOfObjects::Create();
  mapping.getAs3DObject(objs);

  // Count the number of landmarks
  int objs_counter = 0;
  while (objs->getByClass<mrpt::opengl::CEllipsoid>(objs_counter))
  {
    objs_counter++;
  }

  mrpt::opengl::CEllipsoidPtr landmark;
  for (size_t i = 0; i < objs_counter; i++)
  {
    landmark = objs->getByClass<mrpt::opengl::CEllipsoid>(i);

    mrpt::math::CMatrixDouble covariance = landmark->getCovMatrix();
    float quantiles = landmark->getQuantiles();

    // mean position
        CPose3D pose = mrpt::poses::CPose3D(landmark->getPose());  // pose of the robot and landmarks (x,y,z=0)

    // covariance ellipses
    tf::Quaternion orientation;
    Eigen::Vector2d scale;

    computeEllipseOrientationScale2D(orientation, scale, covariance);

    marker.id++;
    marker.color.a = 1.0;
    if (i == 0)
    {  // robot position
      marker.color.r = 1.0;
      marker.color.g = 0.0;
      marker.color.b = 0.0;
    }
    else
    {
      marker.color.r = 0.0;
      marker.color.g = 0.0;
      marker.color.b = 1.0;
    }
    marker.type = visualization_msgs::Marker::SPHERE;
    marker.pose.position.x = pose.x();
    marker.pose.position.y = pose.y();
    marker.pose.position.z = 0;
    marker.pose.orientation.x = orientation.x();
    marker.pose.orientation.y = orientation.y();
    marker.pose.orientation.z = orientation.z();
    marker.pose.orientation.w = orientation.w();
    marker.scale.x = ellipse_scale_ * quantiles * sqrt(scale[0]);
    marker.scale.y = ellipse_scale_ * quantiles * sqrt(scale[1]);
    marker.scale.z = 0.00001;  // Z can't be 0, limitation of ROS
    ma.markers.push_back(marker);

    marker.id++;
    marker.type = visualization_msgs::Marker::TEXT_VIEW_FACING;
    if (i == 0)
    {
      marker.text = "robot";
    }
    else
    {
      marker.text = std::to_string(LM_IDs_[i]);
    }
    marker.pose.position.x = pose.x();
    marker.pose.position.y = pose.y();
    marker.pose.position.z = 0.1;
    marker.color.r = 1.0;
    marker.color.g = 1.0;
    marker.color.b = 1.0;
    marker.scale.x = 0.3;
    marker.scale.y = 0.3;
    marker.scale.z = 0.3;
    ma.markers.push_back(marker);
  }

  state_viz_pub_.publish(ma);
}

void EKFslamWrapper::publishTF()
{
  mapping.getCurrentState(robotPose_, LMs_, LM_IDs_, fullState_, fullCov_);
  // Most of this code was copy and pase from ros::amcl
  mrpt::poses::CPose3D robotPose;
  robotPose = CPose3D(robotPose_.mean);

  tf::Stamped<tf::Pose> odom_to_map;
  tf::Transform tmp_tf;
  ros::Time stamp;
  mrpt_bridge::convert(timeLastUpdate_, stamp);
  mrpt_bridge::convert(robotPose, tmp_tf);

  try
  {
    tf::Stamped<tf::Pose> tmp_tf_stamped(tmp_tf.inverse(), stamp, base_frame_id);
    listenerTF_.transformPose(odom_frame_id, tmp_tf_stamped, odom_to_map);
  }
  catch (tf::TransformException)
  {
    ROS_INFO("Failed to subtract global_frame (%s) from odom_frame (%s)", global_frame_id.c_str(),
             odom_frame_id.c_str());
    return;
  }

  tf::Transform latest_tf_ =
      tf::Transform(tf::Quaternion(odom_to_map.getRotation()), tf::Point(odom_to_map.getOrigin()));

  // We want to send a transform that is good up until a
  // tolerance time so that odom can be used
  ros::Duration transform_tolerance_(0.1);
  ros::Time transform_expiration = (stamp + transform_tolerance_);
  tf::StampedTransform tmp_tf_stamped(latest_tf_.inverse(), transform_expiration, global_frame_id, odom_frame_id);
  tf_broadcaster_.sendTransform(tmp_tf_stamped);
}