CAbstractPTGBasedReactive.h

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/* +---------------------------------------------------------------------------+
   |                     Mobile Robot Programming Toolkit (MRPT)               |
   |                          http://www.mrpt.org/                             |
   |                                                                           |
   | Copyright (c) 2005-2017, Individual contributors, see AUTHORS file        |
   | See: http://www.mrpt.org/Authors - All rights reserved.                   |
   | Released under BSD License. See details in http://www.mrpt.org/License    |
   +---------------------------------------------------------------------------+ */
#ifndef CAbstractPTGBasedReactive_H
#define CAbstractPTGBasedReactive_H

#include <mrpt/nav/reactive/CWaypointsNavigator.h>
#include <mrpt/nav/tpspace/CParameterizedTrajectoryGenerator.h>
#include <mrpt/nav/reactive/CLogFileRecord.h>
#include <mrpt/nav/holonomic/CAbstractHolonomicReactiveMethod.h>
#include <mrpt/nav/holonomic/ClearanceDiagram.h>
#include <mrpt/nav/reactive/TCandidateMovementPTG.h>
#include <mrpt/nav/reactive/CMultiObjectiveMotionOptimizerBase.h>
#include <mrpt/utils/CTimeLogger.h>
#include <mrpt/system/datetime.h>
#include <mrpt/math/filters.h>
#include <mrpt/synch/CCriticalSection.h>
#include <mrpt/math/CPolygon.h>
#include <mrpt/maps/CPointCloudFilterBase.h>

namespace mrpt
{
  namespace nav
  {
        /** Base class for reactive navigator systems based on TP-Space, with an arbitrary holonomic
          * reactive method running on it and any number of PTGs for transforming the navigation space.
          * Both, the holonomic method and the PTGs can be customized by the apropriate user derived classes.
          *
          * How to use:
          *  - Instantiate a reactive navigation object (one of the derived classes of this virtual class).
          *  - A class with callbacks must be defined by the user and provided to the constructor (derived from CRobot2NavInterface)
          *  - loadConfigFile() must be called to set up the bunch of parameters from a config file (could be a memory-based virtual config file).
          *  - navigationStep() must be called periodically in order to effectively run the navigation. This method will internally call the callbacks to gather sensor data and robot positioning data.
          *
          * For working examples, refer to the source code of the apps:
          *  - [ReactiveNavigationDemo](http://www.mrpt.org/list-of-mrpt-apps/application-reactivenavigationdemo/)
          *  - [ReactiveNav3D-Demo](http://www.mrpt.org/list-of-mrpt-apps/application-reactivenav3d-demo/)
          *
          * Publications:
          *  - See derived classes for papers on each specific method.
          *
          * Available "variables" or "score names" for each motion candidate (these can be used in runtime-compiled expressions
          * in the configuration files of motion deciders):
          *
          * - `clearance`: Clearance (larger means larger distances to obstacles) for the path from "current pose" up to "end of trajectory".
          * - `collision_free_distance`: Normalized [0,1] collision-free distance in selected path. For NOP candidates, the traveled distances is substracted.
          * - `dist_eucl_final`: Euclidean distance (in the real-world WordSpace) between "end of trajectory" and target.
          * - `eta`: Estimated Time of Arrival at "end of trajectory".
          * - `holo_stage_eval`: Final evaluation of the selected direction from inside of the holonomic algorithm. 
          * - `hysteresis`: Measure of similarity with previous command [0,1]
          * - `is_PTG_cont`: 1 (is "NOP" motion command), 0 otherwise
          * - `is_slowdown`: 1 if PTG returns true in CParameterizedTrajectoryGenerator::supportSpeedAtTarget() for this step.
          * - `move_cur_d`: Normalized distance already traveled over the selected PTG. Normally 0, unless in a "NOP motion".
          * - `move_k`: Motion candidate path 0-based index.
          * - `num_paths`: Number of paths in the PTG
          * - `original_col_free_dist`: Only for "NOP motions", the collision-free distance when the motion command was originally issued.
          * - `ptg_idx`: PTG index (0-based)
          * - `ptg_priority`: Product of PTG getScorePriority() times PTG evalPathRelativePriority()
          * - `ref_dist`: PTG ref distance [m]
          * - `robpose_x`, `robpose_y`, `robpose_phi`: Robot pose ([m] and [rad]) at the "end of trajectory": at collision or at target distance.
          * - `target_d_norm`: Normalized target distance. Can be >1 if distance is larger than ref_distance.
          * - `target_dir`: Angle of target in TP-Space [rad]
          * - `target_k`: Same as target_dir but in discrete path 0-based indices.
          * - `WS_target_x`, `WS_target_y`: Target coordinates in realworld [m]
          *
          * \sa CReactiveNavigationSystem, CReactiveNavigationSystem3D
          *  \ingroup nav_reactive
          */
        class NAV_IMPEXP CAbstractPTGBasedReactive: public CWaypointsNavigator
        {
        public:
                MRPT_MAKE_ALIGNED_OPERATOR_NEW

                /** The struct for configuring navigation requests to CAbstractPTGBasedReactive and derived classes. */
                struct NAV_IMPEXP TNavigationParamsPTG : public CWaypointsNavigator::TNavigationParamsWaypoints
                {
                        /** (Default=empty) Optionally, a list of PTG indices can be sent such that
                         *  the navigator will restrict itself to only employ those PTGs. */
                        std::vector<size_t>    restrict_PTG_indices;

                        virtual std::string getAsText() const MRPT_OVERRIDE;
                        virtual TNavigationParams* clone() const MRPT_OVERRIDE { return new TNavigationParamsPTG(*this); }
                protected:
                        virtual bool isEqual(const CAbstractNavigator::TNavigationParamsBase& o) const MRPT_OVERRIDE;
                };

                /** Constructor.
                  * \param[in] react_iterf_impl An instance of an object that implement all the required interfaces to read from and control a robot.
                  * \param[in] enableConsoleOutput Can be set to false to reduce verbosity.
                  * \param[in] enableLogFile Set to true to enable creation of navigation log files, useful for inspection and debugging.
                  */
                CAbstractPTGBasedReactive(
                        CRobot2NavInterface &react_iterf_impl,
                        bool enableConsoleOutput = true,
                        bool enableLogFile = false,
                        const std::string &logFileDirectory = std::string("./reactivenav.logs"));

                virtual ~CAbstractPTGBasedReactive();

                /** Must be called for loading collision grids, or the first navigation command may last a long time to be executed.
                  * Internally, it just calls STEP1_CollisionGridsBuilder().
                  */
                void initialize() MRPT_OVERRIDE;

                /** Selects which one from the set of available holonomic methods will be used
                        *  into transformed TP-Space, and sets its configuration from a configuration file.
                        * Available methods: class names of those derived from CAbstractHolonomicReactiveMethod
                        */
                void setHolonomicMethod(const std::string & method, const mrpt::utils::CConfigFileBase & cfgBase);

                MRPT_DEPRECATED("Use the signature with a class name string instead of an enum.")
                void setHolonomicMethod(THolonomicMethod method, const mrpt::utils::CConfigFileBase & cfgBase);

                /** Provides a copy of the last log record with information about execution.
                        * \param o An object where the log will be stored into.
                        * \note Log records are not prepared unless either "enableLogFile" is enabled in the constructor or "enableLogFile()" has been called.
                        */
                void getLastLogRecord( CLogFileRecord &o );

                /** Enables keeping an internal registry of navigation logs that can be queried with getLastLogRecord() */
                void enableKeepLogRecords(bool enable=true) { m_enableKeepLogRecords=enable; }

                /** Enables/disables saving log files. */
                void enableLogFile(bool enable);

                /** Changes the prefix for new log files. */
                void setLogFileDirectory(const std::string &sDir) { m_navlogfiles_dir = sDir; }
                std::string getLogFileDirectory() const { return m_navlogfiles_dir; }


                struct NAV_IMPEXP TAbstractPTGNavigatorParams : public mrpt::utils::CLoadableOptions
                {
                        std::string holonomic_method; //!< C++ class name of the holonomic navigation method to run in the transformed TP-Space
                        std::string motion_decider_method; //!< C++ class name of the motion chooser

                        std::string ptg_cache_files_directory; //!< (Default: ".")
                        double ref_distance;          //!< Maximum distance up to obstacles will be considered (D_{max} in papers).
                        double speedfilter_tau;     //!< Time constant (in seconds) for the low-pass filter applied to kinematic velocity commands (default=0: no filtering)

                        /** In normalized distances, the start and end of a ramp function that scales the velocity
                        *  output from the holonomic navigator:
                        *
                        * \code
                        *  velocity scale
                        *   ^
                        *   |           _____________
                        *   |          /
                        * 1 |         /
                        *   |        /
                        * 0 +-------+---|----------------> normalized distance
                        *         Start
                        *              End
                        * \endcode
                        *
                        */
                        double secure_distance_start, secure_distance_end;
                        bool   use_delays_model;
                        double max_distance_predicted_actual_path; //!< Max distance [meters] to discard current PTG and issue a new vel cmd (default= 0.05)
                        double min_normalized_free_space_for_ptg_continuation; //!< Min normalized dist [0,1] after current pose in a PTG continuation to allow it.

                        mrpt::kinematics::CVehicleVelCmd::TVelCmdParams robot_absolute_speed_limits; //!< Params related to speed limits.
                        bool  enable_obstacle_filtering;
                        bool  evaluate_clearance; //!< Default: false
                        double max_dist_for_timebased_path_prediction; //!< Max dist [meters] to use time-based path prediction for NOP evaluation.

                        virtual void loadFromConfigFile(const mrpt::utils::CConfigFileBase &c, const std::string &s) MRPT_OVERRIDE;
                        virtual void saveToConfigFile(mrpt::utils::CConfigFileBase &c, const std::string &s) const MRPT_OVERRIDE;
                        TAbstractPTGNavigatorParams();
                };

                TAbstractPTGNavigatorParams params_abstract_ptg_navigator;

                virtual void loadConfigFile(const mrpt::utils::CConfigFileBase &c) MRPT_OVERRIDE; // See base class docs!
                virtual void saveConfigFile(mrpt::utils::CConfigFileBase &c) const MRPT_OVERRIDE; // See base class docs!


                /** Enables/disables the detailed time logger (default:disabled upon construction)
                        *  When enabled, a report will be dumped to std::cout upon destruction.
                        * \sa getTimeLogger
                        */
                void enableTimeLog(bool enable=true) {
                        m_timelogger.enable(enable);
                }

                /** Gives access to a const-ref to the internal time logger \sa enableTimeLog */
                const mrpt::utils::CTimeLogger & getTimeLogger() const { return m_timelogger; }

                virtual size_t getPTG_count() const = 0;  //!< Returns the number of different PTGs that have been setup
                virtual CParameterizedTrajectoryGenerator* getPTG(size_t i) = 0; //!< Gets the i'th PTG
                virtual const CParameterizedTrajectoryGenerator* getPTG(size_t i) const = 0; //!< Gets the i'th PTG

                /** Get the current, global (honored for all PTGs) robot speed limits */
                const mrpt::kinematics::CVehicleVelCmd::TVelCmdParams & getCurrentRobotSpeedLimits() const {
                        return params_abstract_ptg_navigator.robot_absolute_speed_limits;
                }

                /** Changes the current, global (honored for all PTGs) robot speed limits, via returning a reference to a structure that holds those limits */
                mrpt::kinematics::CVehicleVelCmd::TVelCmdParams & changeCurrentRobotSpeedLimits() {
                        return params_abstract_ptg_navigator.robot_absolute_speed_limits;
                }

                void setTargetApproachSlowDownDistance(const double dist);  //!< Changes this parameter in all inner holonomic navigator instances [m].
                double getTargetApproachSlowDownDistance() const;  //!< Returns this parameter for the first inner holonomic navigator instances  [m] (should be the same in all of them?)

        protected:
                /** The main method for the navigator */
                virtual void performNavigationStep() MRPT_OVERRIDE;

                std::vector<CAbstractHolonomicReactiveMethod*>  m_holonomicMethod;   //!< The holonomic navigation algorithm (one object per PTG, so internal states are maintained)
                mrpt::utils::CStream  *m_logFile, *m_prev_logfile;         //!< The current log file stream, or NULL if not being used
                bool                   m_enableKeepLogRecords; //!< See enableKeepLogRecords
                CLogFileRecord lastLogRecord;  //!< The last log
                mrpt::kinematics::CVehicleVelCmdPtr m_last_vel_cmd ; //!< Last velocity commands

                mrpt::synch::CCriticalSectionRecursive  m_critZoneLastLog; //!< Critical zones

                bool    m_enableConsoleOutput;  //!< Enables / disables the console debug output.
                bool    m_init_done;            //!< Whether \a loadConfigFile() has been called or not.
                mrpt::utils::CTicTac    timerForExecutionPeriod;

                mrpt::utils::CTimeLogger m_timelogger; //!< A complete time logger \sa enableTimeLog()
                bool  m_PTGsMustBeReInitialized;

                /** @name Variables for CReactiveNavigationSystem::performNavigationStep
                        @{ */
                mrpt::utils::CTicTac totalExecutionTime, executionTime, tictac;
                mrpt::math::LowPassFilter_IIR1  meanExecutionTime;
                mrpt::math::LowPassFilter_IIR1  meanTotalExecutionTime;
                mrpt::math::LowPassFilter_IIR1  meanExecutionPeriod;    //!< Runtime estimation of execution period of the method.
                mrpt::math::LowPassFilter_IIR1  tim_changeSpeed_avr, timoff_obstacles_avr, timoff_curPoseAndSpeed_avr, timoff_sendVelCmd_avr;
                /** @} */

                virtual bool impl_waypoint_is_reachable(const mrpt::math::TPoint2D &wp_local_wrt_robot) const MRPT_OVERRIDE; // See docs in base class

                // Steps for the reactive navigation sytem.
                // ----------------------------------------------------------------------------
                virtual void STEP1_InitPTGs() = 0;

                /** Return false on any fatal error */
                virtual bool implementSenseObstacles(mrpt::system::TTimeStamp &obs_timestamp) = 0;
                bool STEP2_SenseObstacles();

                /** Builds TP-Obstacles from Workspace obstacles for the given PTG.
                  * "out_TPObstacles" is already initialized to the proper length and maximum collision-free distance for each "k" trajectory index.
                  * Distances are in "pseudo-meters". They will be normalized automatically to [0,1] upon return. */
                virtual void STEP3_WSpaceToTPSpace(const size_t ptg_idx,std::vector<double> &out_TPObstacles, mrpt::nav::ClearanceDiagram &out_clearance, const mrpt::math::TPose2D &rel_pose_PTG_origin_wrt_sense, const bool eval_clearance) = 0;

                /** Generates a pointcloud of obstacles, and the robot shape, to be saved in the logging record for the current timestep */
                virtual void loggingGetWSObstaclesAndShape(CLogFileRecord &out_log) = 0;

                struct PTGTarget
                {
                        bool                 valid_TP;   //!< For each PTG, whether target falls into the PTG domain.
                        mrpt::math::TPoint2D TP_Target;  //!< The Target, in TP-Space (x,y)
                        double               target_alpha, target_dist;  //!< TP-Target
                        int                  target_k; //!< The discrete version of target_alpha

                        PTGTarget() : valid_TP(false) {}
                };

                /** Scores \a holonomicMovement */
                void calc_move_candidate_scores(TCandidateMovementPTG         & holonomicMovement,
                        const std::vector<double>        & in_TPObstacles,
                        const mrpt::nav::ClearanceDiagram & in_clearance,
                        const std::vector<mrpt::math::TPose2D>  & WS_Targets,
                        const std::vector<PTGTarget> & TP_Targets,
                        CLogFileRecord::TInfoPerPTG & log,
                        CLogFileRecord & newLogRec,
                        const bool this_is_PTG_continuation,
                        const mrpt::math::TPose2D &relPoseVelCmd_NOP,
                        const unsigned int ptg_idx4weights,
                        const mrpt::system::TTimeStamp tim_start_iteration,
                        const mrpt::nav::CHolonomicLogFileRecordPtr &hlfr);

                /** Return the [0,1] velocity scale of raw PTG cmd_vel */
                virtual double generate_vel_cmd(const TCandidateMovementPTG &in_movement, mrpt::kinematics::CVehicleVelCmdPtr &new_vel_cmd );
                void STEP8_GenerateLogRecord(CLogFileRecord &newLogRec, const std::vector<mrpt::math::TPose2D>& relTargets, int nSelectedPTG, const mrpt::kinematics::CVehicleVelCmdPtr &new_vel_cmd, int nPTGs, const bool best_is_NOP_cmdvel, const math::TPose2D &rel_cur_pose_wrt_last_vel_cmd_NOP, const math::TPose2D &rel_pose_PTG_origin_wrt_sense_NOP, const double executionTimeValue, const double tim_changeSpeed, const mrpt::system::TTimeStamp &tim_start_iteration);
                void preDestructor(); //!< To be called during children destructors to assure thread-safe destruction, and free of shared objects.
                virtual void onStartNewNavigation() MRPT_OVERRIDE;

                bool m_closing_navigator; //!< Signal that the destructor has been called, so no more calls are accepted from other threads

                mrpt::system::TTimeStamp m_WS_Obstacles_timestamp;
                mrpt::maps::CPointCloudFilterBasePtr m_WS_filter;   //!< Default: none

                mrpt::nav::CMultiObjectiveMotionOptimizerBasePtr m_multiobjopt;


                struct TInfoPerPTG
                {
                        std::vector<PTGTarget> targets;
                        std::vector<double>  TP_Obstacles; //!< One distance per discretized alpha value, describing the "polar plot" of TP obstacles.
                        ClearanceDiagram     clearance;    //!< Clearance for each path
                };

                std::vector<TInfoPerPTG> m_infoPerPTG; //!< Temporary buffers for working with each PTG during a navigationStep()
                mrpt::system::TTimeStamp m_infoPerPTG_timestamp;

                void build_movement_candidate(CParameterizedTrajectoryGenerator * ptg,
                        const size_t indexPTG,
                        const std::vector<mrpt::math::TPose2D> &relTargets,
                        const mrpt::math::TPose2D &rel_pose_PTG_origin_wrt_sense,
                        TInfoPerPTG &ipf,
                        TCandidateMovementPTG &holonomicMovement,
                        CLogFileRecord &newLogRec,
                        const bool this_is_PTG_continuation,
                        mrpt::nav::CAbstractHolonomicReactiveMethod *holoMethod,
                        const mrpt::system::TTimeStamp tim_start_iteration,
                        const TNavigationParams &navp = TNavigationParams(),
                        const mrpt::math::TPose2D &relPoseVelCmd_NOP = mrpt::poses::CPose2D()
                );

                struct NAV_IMPEXP TSentVelCmd
                {
                        int ptg_index; //!< 0-based index of used PTG
                        int ptg_alpha_index; //!< Path index for selected PTG
                        mrpt::system::TTimeStamp tim_send_cmd_vel; //!< Timestamp of when the cmd was sent
                        TRobotPoseVel  poseVel;  //!< Robot pose & velocities and timestamp of when it was queried
                        double colfreedist_move_k; //!< TP-Obstacles in the move direction at the instant of picking this movement
                        bool   was_slowdown;
                        double speed_scale;        //!< [0,1] scale of the raw cmd_vel as generated by the PTG
                        double original_holo_eval;
                        CParameterizedTrajectoryGenerator::TNavDynamicState ptg_dynState;

                        bool isValid() const;
                        void reset();
                        TSentVelCmd();
                };

                TSentVelCmd m_lastSentVelCmd;

        private:
                void deleteHolonomicObjects(); //!< Delete m_holonomicMethod

                std::string m_navlogfiles_dir; //!< Default: "./reactivenav.logs"

                double m_expr_var_k, m_expr_var_k_target, m_expr_var_num_paths;
                TNavigationParams  *m_copy_prev_navParams; //!< A copy of last-iteration navparams, used to detect changes
                
        }; // end of CAbstractPTGBasedReactive
  }
}


#endif