range.cpp

// Copyright (c) 2022 Samsung R&D Institute Russia
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
 
#include "nav2_collision_monitor/range.hpp"
 
#include <math.h>
#include <cmath>
#include <functional>
 
#include "tf2/transform_datatypes.hpp"
#include "nav2_ros_common/tf2_factories.hpp"
 
#include "nav2_ros_common/node_utils.hpp"
#include "nav2_ros_common/validate_messages.hpp"
#include "nav2_util/robot_utils.hpp"
 
namespace nav2_collision_monitor
{
 
constexpr size_t MAX_RANGE_DATA_POINTS = 1e4;
 
Range::Range(
  const nav2::LifecycleNode::WeakPtr & node,
  const std::string & source_name,
  const nav2::TransformBuffer::SharedPtr tf_buffer,
  const std::string & base_frame_id,
  const std::string & global_frame_id,
  const tf2::Duration & transform_tolerance,
  const rclcpp::Duration & source_timeout,
  const bool base_shift_correction)
: Source(
    node, source_name, tf_buffer, base_frame_id, global_frame_id,
    transform_tolerance, source_timeout, base_shift_correction),
  data_(nullptr)
{
  RCLCPP_INFO(logger_, "[%s]: Creating Range", source_name_.c_str());
}
 
Range::~Range()
{
  RCLCPP_INFO(logger_, "[%s]: Destroying Range", source_name_.c_str());
  data_sub_.reset();
}
 
bool Range::configure()
{
  if (!Source::configure()) {
    return false;
  }
  auto node = node_.lock();
  if (!node) {
    throw std::runtime_error{"Failed to lock node"};
  }
 
  std::string source_topic;
 
  getParameters(source_topic);
 
  data_sub_ = node->create_subscription<sensor_msgs::msg::Range>(
    source_topic,
    std::bind(&Range::dataCallback, this, std::placeholders::_1),
    nav2::qos::SensorDataQoS());
 
  return true;
}
 
bool Range::getSourceData(
  const rclcpp::Time & curr_time,
  std::vector<Point> & data)
{
  // Ignore data from the source if it is not being published yet or
  // not being published for a long time
  if (data_ == nullptr) {
    return false;
  }
  if (!sourceValid(data_->header.stamp, curr_time)) {
    return false;
  }
 
  // Ignore data, if its range is out of scope of range sensor abilities
  if (data_->range < data_->min_range || data_->range > data_->max_range) {
    RCLCPP_DEBUG(
      logger_,
      "[%s]: Data range %fm is out of {%f..%f} sensor span. Ignoring...",
      source_name_.c_str(), data_->range, data_->min_range, data_->max_range);
    return false;
  }
 
  const size_t point_count = static_cast<size_t>(
    std::ceil(static_cast<double>(data_->field_of_view) / obstacles_angle_)) + 1;
  if (point_count > MAX_RANGE_DATA_POINTS) {
    RCLCPP_ERROR(
      logger_,
      "[%s]: Range data would generate %zu points, exceeding the limit of %zu. Ignoring...",
      source_name_.c_str(), point_count, MAX_RANGE_DATA_POINTS);
    return false;
  }
 
  tf2::Transform tf_transform;
  if (!getTransform(curr_time, data_->header, tf_transform)) {
    return false;
  }
 
  // Calculate poses and refill data array
  float angle;
  for (
    angle = -data_->field_of_view / 2;
    angle < data_->field_of_view / 2;
    angle += obstacles_angle_)
  {
    // Transform point coordinates from source frame -> to base frame
    tf2::Vector3 p_v3_s(
      data_->range * std::cos(angle),
      data_->range * std::sin(angle),
      0.0);
    tf2::Vector3 p_v3_b = tf_transform * p_v3_s;
 
    // Refill data array
    data.push_back({p_v3_b.x(), p_v3_b.y(), p_v3_b.z(), source_name_});
  }
 
  // Make sure that last (field_of_view / 2) point will be in the data array
  angle = data_->field_of_view / 2;
 
  // Transform point coordinates from source frame -> to base frame
  tf2::Vector3 p_v3_s(
    data_->range * std::cos(angle),
    data_->range * std::sin(angle),
    0.0);
  tf2::Vector3 p_v3_b = tf_transform * p_v3_s;
 
  // Refill data array
  data.push_back({p_v3_b.x(), p_v3_b.y(), p_v3_b.z(), source_name_});
 
  return true;
}
 
void Range::getParameters(std::string & source_topic)
{
  auto node = node_.lock();
  if (!node) {
    throw std::runtime_error{"Failed to lock node"};
  }
 
  getCommonParameters(source_topic);
 
  obstacles_angle_ = node->declare_or_get_parameter(
    source_name_ + ".obstacles_angle", M_PI / 180);
 
  if (!std::isfinite(obstacles_angle_) || obstacles_angle_ <= 0.0) {
    throw std::runtime_error{
            "Range source " + source_name_ + " has invalid obstacles_angle parameter"};
  }
}
 
void Range::dataCallback(sensor_msgs::msg::Range::ConstSharedPtr msg)
{
  if (!nav2::validateMsg(*msg)) {
    RCLCPP_ERROR(
      logger_,
      "[%s]: Malformed range message. Rejecting...",
      source_name_.c_str());
    return;
  }
 
  data_ = msg;
}
 
}  // namespace nav2_collision_monitor