xy_theta_iterator.cpp

/*
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#include "dwb_plugins/xy_theta_iterator.hpp"
 
#include <cmath>
#include <memory>
#include <string>
 
#include "nav_2d_utils/parameters.hpp"
#include "nav2_util/node_utils.hpp"
 
#define EPSILON 1E-5
 
namespace dwb_plugins
{
void XYThetaIterator::initialize(
  const nav2_util::LifecycleNode::SharedPtr & nh,
  KinematicsHandler::Ptr kinematics,
  const std::string & plugin_name)
{
  kinematics_handler_ = kinematics;
 
  nav2_util::declare_parameter_if_not_declared(
    nh,
    plugin_name + ".vx_samples", rclcpp::ParameterValue(20));
  nav2_util::declare_parameter_if_not_declared(
    nh,
    plugin_name + ".vy_samples", rclcpp::ParameterValue(5));
  nav2_util::declare_parameter_if_not_declared(
    nh,
    plugin_name + ".vtheta_samples", rclcpp::ParameterValue(20));
 
  nh->get_parameter(plugin_name + ".vx_samples", vx_samples_);
  nh->get_parameter(plugin_name + ".vy_samples", vy_samples_);
  nh->get_parameter(plugin_name + ".vtheta_samples", vtheta_samples_);
}
 
void XYThetaIterator::startNewIteration(
  const nav_2d_msgs::msg::Twist2D & current_velocity,
  double dt)
{
  KinematicParameters kinematics = kinematics_handler_->getKinematics();
  x_it_ = std::make_shared<OneDVelocityIterator>(
    current_velocity.x,
    kinematics.getMinX(), kinematics.getMaxX(),
    kinematics.getAccX(), kinematics.getDecelX(),
    dt, vx_samples_);
  y_it_ = std::make_shared<OneDVelocityIterator>(
    current_velocity.y,
    kinematics.getMinY(), kinematics.getMaxY(),
    kinematics.getAccY(), kinematics.getDecelY(),
    dt, vy_samples_);
  th_it_ = std::make_shared<OneDVelocityIterator>(
    current_velocity.theta,
    kinematics.getMinTheta(), kinematics.getMaxTheta(),
    kinematics.getAccTheta(), kinematics.getDecelTheta(),
    dt, vtheta_samples_);
  if (!isValidVelocity()) {
    iterateToValidVelocity();
  }
}
 
bool XYThetaIterator::isValidSpeed(double x, double y, double theta)
{
  KinematicParameters kinematics = kinematics_handler_->getKinematics();
  double vmag_sq = x * x + y * y;
  if (kinematics.getMaxSpeedXY() >= 0.0 && vmag_sq > kinematics.getMaxSpeedXY_SQ() + EPSILON) {
    return false;
  }
  if (kinematics.getMinSpeedXY() >= 0.0 && vmag_sq + EPSILON < kinematics.getMinSpeedXY_SQ() &&
    kinematics.getMinSpeedTheta() >= 0.0 && fabs(theta) + EPSILON < kinematics.getMinSpeedTheta())
  {
    return false;
  }
  if (vmag_sq == 0.0 && th_it_->getVelocity() == 0.0) {
    return false;
  }
  return true;
}
 
bool XYThetaIterator::isValidVelocity()
{
  return isValidSpeed(
    x_it_->getVelocity(), y_it_->getVelocity(),
    th_it_->getVelocity());
}
 
bool XYThetaIterator::hasMoreTwists()
{
  return x_it_ && !x_it_->isFinished();
}
 
nav_2d_msgs::msg::Twist2D XYThetaIterator::nextTwist()
{
  nav_2d_msgs::msg::Twist2D velocity;
  velocity.x = x_it_->getVelocity();
  velocity.y = y_it_->getVelocity();
  velocity.theta = th_it_->getVelocity();
 
  iterateToValidVelocity();
 
  return velocity;
}
 
void XYThetaIterator::iterateToValidVelocity()
{
  bool valid = false;
  while (!valid && hasMoreTwists()) {
    ++(*th_it_);
    if (th_it_->isFinished()) {
      th_it_->reset();
      ++(*y_it_);
      if (y_it_->isFinished()) {
        y_it_->reset();
        ++(*x_it_);
      }
    }
    valid = isValidVelocity();
  }
}
 
}  // namespace dwb_plugins