cartographer---第一篇

0、整体架构

1、cartographer_ros

　　我们先看cartographer_ros 是怎样接入 cartographer的？ cartographer_ros 在node_main中调用了cartographer::mapping::CreateMapBuilder（），Node对象构建；然后从cartographer中引进cartographer::mapping::MapBuilderInterface，构建了MapBuilderBridge类，所有方法由MapBuilderBridge转进Ros；如下图

cartographer---第一篇

LaunchSubscribers（）通过SensorBridge将imu scan等topic数据转换后，传进map_builder_bridge_进行处理。

int Node::AddTrajectory(const TrajectoryOptions& options) {
  const std::set<cartographer::mapping::TrajectoryBuilderInterface::SensorId>
      expected_sensor_ids = ComputeExpectedSensorIds(options);
  const int trajectory_id =
      map_builder_bridge_.AddTrajectory(expected_sensor_ids, options);
  AddExtrapolator(trajectory_id, options);
  AddSensorSamplers(trajectory_id, options);
  LaunchSubscribers(options, trajectory_id);
  wall_timers_.push_back(node_handle_.createWallTimer(
      ::ros::WallDuration(kTopicMismatchCheckDelaySec),
      &Node::MaybeWarnAboutTopicMismatch, this, /*oneshot=*/true));
  for (const auto& sensor_id : expected_sensor_ids) {
    subscribed_topics_.insert(sensor_id.id);
  }
  return trajectory_id;
}