limited_accel_generator.cpp

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#include "dwb_plugins/limited_accel_generator.hpp"
#include <vector>
#include <memory>
#include <string>
#include "pluginlib/class_list_macros.hpp"
#include "dwb_core/exceptions.hpp"
#include "nav2_ros_common/node_utils.hpp"
 
namespace dwb_plugins
{
 
void LimitedAccelGenerator::initialize(
  const nav2::LifecycleNode::SharedPtr & nh,
  const std::string & plugin_name)
{
  plugin_name_ = plugin_name;
  StandardTrajectoryGenerator::initialize(nh, plugin_name_);
 
  try {
    nav2::declare_parameter_if_not_declared(
      nh, plugin_name + ".sim_period", rclcpp::PARAMETER_DOUBLE);
    if (!nh->get_parameter(plugin_name + ".sim_period", acceleration_time_)) {
      // This actually should never appear, since declare_parameter_if_not_declared()
      // completed w/o exceptions guarantee that static parameter will be initialized
      // with some value. However for reliability we should also process the case
      // when get_parameter() will return a failure for some other reasons.
      throw std::runtime_error("Failed to get 'sim_period' value");
    }
  } catch (std::exception &) {
    RCLCPP_WARN(
      rclcpp::get_logger("LimitedAccelGenerator"),
      "'sim_period' parameter is not set for %s", plugin_name.c_str());
    double controller_frequency = nh->declare_or_get_parameter("controller_frequency", 20.0);
    if (controller_frequency > 0) {
      acceleration_time_ = 1.0 / controller_frequency;
    } else {
      RCLCPP_WARN(
        rclcpp::get_logger("LimitedAccelGenerator"),
        "A controller_frequency less than or equal to 0 has been set. "
        "Ignoring the parameter, assuming a rate of 20Hz");
      acceleration_time_ = 0.05;
    }
  }
}
 
void LimitedAccelGenerator::startNewIteration(const nav_2d_msgs::msg::Twist2D & current_velocity)
{
  // Limit our search space to just those within the limited acceleration_time
  velocity_iterator_->startNewIteration(current_velocity, acceleration_time_);
}
 
nav_2d_msgs::msg::Twist2D LimitedAccelGenerator::computeNewVelocity(
  const nav_2d_msgs::msg::Twist2D & cmd_vel,
  const nav_2d_msgs::msg::Twist2D & /*start_vel*/,
  const double /*dt*/)
{
  return cmd_vel;
}
 
}  // namespace dwb_plugins
 
PLUGINLIB_EXPORT_CLASS(dwb_plugins::LimitedAccelGenerator, dwb_core::TrajectoryGenerator)