standard_traj_generator.h

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#ifndef DWB_PLUGINS_STANDARD_TRAJ_GENERATOR_H
#define DWB_PLUGINS_STANDARD_TRAJ_GENERATOR_H

#include <ros/ros.h>
#include <dwb_local_planner/trajectory_generator.h>
#include <dwb_plugins/velocity_iterator.h>
#include <dwb_plugins/kinematic_parameters.h>
#include <vector>
#include <memory>

namespace dwb_plugins
{

class StandardTrajectoryGenerator : public dwb_local_planner::TrajectoryGenerator
{
public:
  // Standard TrajectoryGenerator interface
  void initialize(ros::NodeHandle& nh) override;
  void startNewIteration(const nav_2d_msgs::Twist2D& current_velocity) override;
  bool hasMoreTwists() override;
  nav_2d_msgs::Twist2D nextTwist() override;

  dwb_msgs::Trajectory2D generateTrajectory(const geometry_msgs::Pose2D& start_pose,
      const nav_2d_msgs::Twist2D& start_vel,
      const nav_2d_msgs::Twist2D& cmd_vel) override;
protected:
  virtual void initializeIterator(ros::NodeHandle& nh);

  virtual void checkUseDwaParam(const ros::NodeHandle& nh);

  virtual nav_2d_msgs::Twist2D computeNewVelocity(const nav_2d_msgs::Twist2D& cmd_vel,
                                                  const nav_2d_msgs::Twist2D& start_vel,
                                                  const double dt);

  virtual geometry_msgs::Pose2D computeNewPosition(const geometry_msgs::Pose2D start_pose,
                                                   const nav_2d_msgs::Twist2D& vel,
                                                   const double dt);


  virtual std::vector<double> getTimeSteps(const nav_2d_msgs::Twist2D& cmd_vel);

  KinematicParameters::Ptr kinematics_;
  std::shared_ptr<VelocityIterator> velocity_iterator_;

  double sim_time_;

  // Sampling Parameters
  bool discretize_by_time_;
  double time_granularity_;     
  double linear_granularity_;   
  double angular_granularity_;  

  /* Backwards Compatibility Parameter: include_last_point
   *
   * dwa had an off-by-one error built into it.
   * It generated N trajectory points, where N = ceil(sim_time / time_delta).
   * If for example, sim_time=3.0 and time_delta=1.5, it would generate trajectories with 2 points, which
   * indeed were time_delta seconds apart. However, the points would be at t=0 and t=1.5, and thus the
   * actual sim_time was much less than advertised.
   *
   * This is remedied by adding one final point at t=sim_time, but only if include_last_point_ is true.
   *
   * Nothing I could find actually used the time_delta variable or seemed to care that the trajectories
   * were not projected out as far as they intended.
   */
  bool include_last_point_;
};


}  // namespace dwb_plugins

#endif  // DWB_PLUGINS_STANDARD_TRAJ_GENERATOR_H