CWaypointsNavigator.cpp

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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 |
   +------------------------------------------------------------------------+ */

#include "nav-precomp.h"  // Precomp header

#include <mrpt/nav/reactive/CWaypointsNavigator.h>
#include <mrpt/poses/CPose2D.h>
#include <mrpt/math/wrap2pi.h>

using namespace mrpt::nav;
using namespace std;

std::string CWaypointsNavigator::TNavigationParamsWaypoints::getAsText() const
{
        std::string s = TNavigationParams::getAsText();
        if (!multiple_targets.empty())
        {
                s += "multiple_targets:\n";
                int i = 0;
                for (const auto& e : multiple_targets)
                {
                        s += mrpt::format("target[%i]:\n", i++);
                        s += e.getAsText();
                }
        }
        return s;
}

bool CWaypointsNavigator::TNavigationParamsWaypoints::isEqual(
        const CAbstractNavigator::TNavigationParamsBase& rhs) const
{
        auto o =
                dynamic_cast<const CWaypointsNavigator::TNavigationParamsWaypoints*>(
                        &rhs);
        return o != nullptr &&
                   CAbstractNavigator::TNavigationParams::isEqual(rhs) &&
                   multiple_targets == o->multiple_targets;
}

CWaypointsNavigator::CWaypointsNavigator(CRobot2NavInterface& robot_if)
        : CAbstractNavigator(robot_if),
          m_was_aligning(false),
          m_is_aligning(false),
          m_last_alignment_cmd(mrpt::system::now())
{
}

CWaypointsNavigator::~CWaypointsNavigator() {}
void CWaypointsNavigator::onNavigateCommandReceived()
{
        CAbstractNavigator::onNavigateCommandReceived();

        std::lock_guard<std::recursive_mutex> csl(m_nav_waypoints_cs);

        m_was_aligning = false;
        m_waypoint_nav_status = TWaypointStatusSequence();
        m_waypoint_nav_status.timestamp_nav_started = INVALID_TIMESTAMP;
        m_waypoint_nav_status.waypoint_index_current_goal = -1;  // Not started yet.
}

void CWaypointsNavigator::navigateWaypoints(
        const TWaypointSequence& nav_request)
{
        MRPT_START

        this->onNavigateCommandReceived();

        std::lock_guard<std::recursive_mutex> csl(m_nav_waypoints_cs);

        m_pending_events.clear();

        const size_t N = nav_request.waypoints.size();
        ASSERTMSG_(N > 0, "List of waypoints is empty!");

        m_waypoint_nav_status.waypoints.resize(N);
        // Copy waypoints fields data, leave status fields to defaults:
        for (size_t i = 0; i < N; i++)
        {
                ASSERT_(nav_request.waypoints[i].isValid());
                m_waypoint_nav_status.waypoints[i] = nav_request.waypoints[i];
        }
        m_waypoint_nav_status.timestamp_nav_started = mrpt::system::now();

        m_waypoint_nav_status.waypoint_index_current_goal = -1;  // Not started yet.

        // The main loop navigationStep() will iterate over waypoints and send them
        // to navigate()
        MRPT_END
}

void CWaypointsNavigator::getWaypointNavStatus(
        TWaypointStatusSequence& out_nav_status) const
{
        // No need to lock mutex...
        out_nav_status = m_waypoint_nav_status;
}

/** \callergraph */
void CWaypointsNavigator::cancel()
{
        {
                std::lock_guard<std::recursive_mutex> csl(m_nav_waypoints_cs);
                m_waypoint_nav_status = TWaypointStatusSequence();
        }
        CAbstractNavigator::cancel();
}

/** \callergraph */
void CWaypointsNavigator::waypoints_navigationStep()
{
        MRPT_START

        using mrpt::math::square;

        // --------------------------------------
        //     Waypoint navigation algorithm
        // --------------------------------------
        m_is_aligning =
                false;  // the robot is aligning into a waypoint with a desired heading

        {
                mrpt::utils::CTimeLoggerEntry tle(
                        m_timlog_delays, "CWaypointsNavigator::navigationStep()");
                std::lock_guard<std::recursive_mutex> csl(m_nav_waypoints_cs);

                TWaypointStatusSequence& wps =
                        m_waypoint_nav_status;  // shortcut to save typing

                if (wps.waypoints.empty() || wps.final_goal_reached)
                {
                        // No nav request is pending or it was canceled
                }
                else
                {
                        // 0) Get current robot pose:
                        CAbstractNavigator::updateCurrentPoseAndSpeeds();

                        // 1) default policy: go thru WPs one by one
                        const int prev_wp_index = wps.waypoint_index_current_goal;

                        mrpt::math::TSegment2D robot_move_seg;
                        robot_move_seg.point1.x = m_curPoseVel.pose.x;
                        robot_move_seg.point1.y = m_curPoseVel.pose.y;
                        if (wps.last_robot_pose.x == TWaypoint::INVALID_NUM)
                        {
                                robot_move_seg.point2 = robot_move_seg.point1;
                        }
                        else
                        {
                                robot_move_seg.point2.x = wps.last_robot_pose.x;
                                robot_move_seg.point2.y = wps.last_robot_pose.y;
                        }
                        wps.last_robot_pose = m_curPoseVel.pose;  // save for next iters

                        if (wps.waypoint_index_current_goal >= 0)
                        {
                                auto& wp = wps.waypoints[wps.waypoint_index_current_goal];
                                const double dist2target = robot_move_seg.distance(wp.target);
                                if (dist2target < wp.allowed_distance ||
                                        m_was_aligning /* we were already aligning at a WP */)
                                {
                                        bool consider_wp_reached = false;
                                        if (wp.target_heading == TWaypoint::INVALID_NUM)
                                        {
                                                consider_wp_reached = true;
                                        }
                                        else
                                        {
                                                // Handle pure-rotation robot interface to honor
                                                // target_heading
                                                const double ang_err = mrpt::math::angDistance(
                                                        m_curPoseVel.pose.phi, wp.target_heading);
                                                const double tim_since_last_align =
                                                        mrpt::system::timeDifference(
                                                                m_last_alignment_cmd, mrpt::system::now());
                                                const double ALIGN_WAIT_TIME = 1.5;  // seconds

                                                if (std::abs(ang_err) <=
                                                                params_waypoints_navigator
                                                                        .waypoint_angle_tolerance &&
                                                        /* give some time for the alignment (if supported in
                                                           this robot) to finish)*/
                                                        tim_since_last_align > ALIGN_WAIT_TIME)
                                                {
                                                        consider_wp_reached = true;
                                                }
                                                else
                                                {
                                                        m_is_aligning = true;

                                                        if (!m_was_aligning)
                                                        {
                                                                // 1st time we are aligning:
                                                                // Send vel_cmd to the robot:
                                                                mrpt::kinematics::CVehicleVelCmd::Ptr
                                                                        align_cmd = m_robot.getAlignCmd(ang_err);

                                                                MRPT_LOG_INFO_FMT(
                                                                        "[CWaypointsNavigator::navigationStep] "
                                                                        "Trying to align to heading: %.02f deg. "
                                                                        "Relative heading: %.02f deg. "
                                                                        "With motion cmd: %s",
                                                                        mrpt::utils::RAD2DEG(wp.target_heading),
                                                                        mrpt::utils::RAD2DEG(ang_err),
                                                                        align_cmd ? align_cmd->asString().c_str()
                                                                                          : "nullptr (operation not "
                                                                                                "supported by this robot)");

                                                                this->stop(false /*not emergency*/);  // In any
                                                                // case,
                                                                // do a
                                                                // "stop"
                                                                if (align_cmd)
                                                                {
                                                                        this->changeSpeeds(*align_cmd);
                                                                }
                                                                else
                                                                {
                                                                        consider_wp_reached =
                                                                                true;  // this robot does not support
                                                                        // "in place" alignment
                                                                }
                                                        }
                                                        else
                                                        {
                                                                MRPT_LOG_THROTTLE_INFO_FMT(
                                                                        0.5,
                                                                        "[CWaypointsNavigator::navigationStep] "
                                                                        "Waiting for the robot to get aligned: "
                                                                        "current_heading=%.02f deg "
                                                                        "target_heading=%.02f deg",
                                                                        mrpt::utils::RAD2DEG(m_curPoseVel.pose.phi),
                                                                        mrpt::utils::RAD2DEG(wp.target_heading));
                                                        }
                                                }
                                        }

                                        if (consider_wp_reached)
                                        {
                                                MRPT_LOG_DEBUG_STREAM(
                                                        "[CWaypointsNavigator::navigationStep] Waypoint "
                                                        << (wps.waypoint_index_current_goal + 1) << "/"
                                                        << wps.waypoints.size()
                                                        << " reached."
                                                           " segment-to-target dist: "
                                                        << dist2target
                                                        << ", allowed_dist: " << wp.allowed_distance);

                                                wp.reached = true;
                                                wp.skipped = false;
                                                wp.timestamp_reach = mrpt::system::now();

                                                m_pending_events.push_back(
                                                        std::bind(
                                                                &CRobot2NavInterface::sendWaypointReachedEvent,
                                                                std::ref(m_robot),
                                                                wps.waypoint_index_current_goal,
                                                                true /*reason: really reached*/));

                                                // Was this the final goal??
                                                if (wps.waypoint_index_current_goal <
                                                        int(wps.waypoints.size() - 1))
                                                {
                                                        wps.waypoint_index_current_goal++;
                                                }
                                                else
                                                {
                                                        wps.final_goal_reached = true;
                                                        // Make sure the end-navigation event is issued,
                                                        // navigation state switches to IDLE, etc:
                                                        this->performNavigationStepNavigating(false);
                                                }
                                        }
                                }
                        }

                        // 2) More advanced policy: if available, use children class methods
                        // to decide
                        //     which is the best candidate for the next waypoint, if we can
                        //     skip current one:
                        if (!wps.final_goal_reached &&
                                wps.waypoint_index_current_goal >= 0 &&
                                wps.waypoints[wps.waypoint_index_current_goal].allow_skip)
                        {
                                const mrpt::poses::CPose2D robot_pose(m_curPoseVel.pose);
                                int most_advanced_wp = wps.waypoint_index_current_goal;
                                const int most_advanced_wp_at_begin = most_advanced_wp;

                                for (int idx = wps.waypoint_index_current_goal;
                                         idx < (int)wps.waypoints.size(); idx++)
                                {
                                        if (idx < 0) continue;
                                        if (wps.waypoints[idx].reached) continue;

                                        // Is it reachable?
                                        mrpt::math::TPoint2D wp_local_wrt_robot;
                                        robot_pose.inverseComposePoint(
                                                wps.waypoints[idx].target, wp_local_wrt_robot);

                                        if (params_waypoints_navigator
                                                                .max_distance_to_allow_skip_waypoint > 0 &&
                                                wp_local_wrt_robot.norm() >
                                                        params_waypoints_navigator
                                                                .max_distance_to_allow_skip_waypoint)
                                                continue;  // Skip this one, it is too far away

                                        const bool is_reachable =
                                                this->impl_waypoint_is_reachable(wp_local_wrt_robot);

                                        if (is_reachable)
                                        {
                                                // Robustness filter: only skip to a future waypoint if
                                                // it is seen as "reachable" during
                                                // a given number of timesteps:
                                                if (++wps.waypoints[idx].counter_seen_reachable >
                                                        params_waypoints_navigator
                                                                .min_timesteps_confirm_skip_waypoints)
                                                {
                                                        most_advanced_wp = idx;
                                                }
                                        }

                                        // Is allowed to skip it?
                                        if (!wps.waypoints[idx].allow_skip)
                                                break;  // Do not keep trying, since we are now allowed
                                        // to skip this one.
                                }

                                if (most_advanced_wp >= 0)
                                {
                                        wps.waypoint_index_current_goal = most_advanced_wp;
                                        for (int k = most_advanced_wp_at_begin;
                                                 k < most_advanced_wp; k++)
                                        {
                                                auto& wp = wps.waypoints[k];
                                                wp.reached = true;
                                                wp.skipped = true;
                                                wp.timestamp_reach = mrpt::system::now();

                                                m_pending_events.push_back(
                                                        std::bind(
                                                                &CRobot2NavInterface::sendWaypointReachedEvent,
                                                                std::ref(m_robot), k,
                                                                false /*reason: skipped*/));
                                        }
                                }
                        }

                        // Still not started and no better guess? Start with the first
                        // waypoint:
                        if (wps.waypoint_index_current_goal < 0)
                                wps.waypoint_index_current_goal = 0;

                        // 3) Should I request a new (single target) navigation command?
                        //    Only if the temporary goal changed:
                        if (wps.waypoint_index_current_goal >= 0 &&
                                prev_wp_index != wps.waypoint_index_current_goal)
                        {
                                ASSERT_(
                                        wps.waypoint_index_current_goal <
                                        int(wps.waypoints.size()));
                                ASSERT_(params_waypoints_navigator.multitarget_look_ahead >= 0);

                                // Notify we have a new "current waypoint"
                                m_pending_events.push_back(
                                        std::bind(
                                                &CRobot2NavInterface::sendNewWaypointTargetEvent,
                                                std::ref(m_robot), wps.waypoint_index_current_goal));

                                // Send the current targets + "multitarget_look_ahead"
                                // additional ones to help the local planner.
                                CWaypointsNavigator::TNavigationParamsWaypoints nav_cmd;

                                // Check skippable flag while traversing from current wp forward
                                // "multitarget_look_ahead" steps:
                                int wp_last_idx = wps.waypoint_index_current_goal;
                                for (int nstep = 0;
                                         wp_last_idx < int(wps.waypoints.size()) - 1 &&
                                         nstep < params_waypoints_navigator.multitarget_look_ahead;
                                         ++nstep)
                                {
                                        if (!m_waypoint_nav_status.waypoints[wp_last_idx]
                                                         .allow_skip)
                                                break;
                                        wp_last_idx++;
                                }

                                for (int wp_idx = wps.waypoint_index_current_goal;
                                         wp_idx <= wp_last_idx; wp_idx++)
                                {
                                        TWaypointStatus& wp = wps.waypoints[wp_idx];
                                        const bool is_final_wp =
                                                ((wp_idx + 1) == int(wps.waypoints.size()));

                                        CAbstractNavigator::TargetInfo ti;

                                        ti.target_coords.x = wp.target.x;
                                        ti.target_coords.y = wp.target.y;
                                        ti.target_coords.phi =
                                                (wp.target_heading != TWaypoint::INVALID_NUM
                                                         ? wp.target_heading
                                                         : .0);
                                        ti.target_frame_id = wp.target_frame_id;
                                        ti.targetAllowedDistance = wp.allowed_distance;
                                        ti.targetIsRelative = false;
                                        ti.targetIsIntermediaryWaypoint = !is_final_wp;
                                        ti.targetDesiredRelSpeed =
                                                (is_final_wp ||
                                                 (wp.target_heading != TWaypoint::INVALID_NUM))
                                                        ? params_waypoints_navigator
                                                                  .rel_speed_for_stop_waypoints
                                                        : 1.;

                                        // For backwards compat. with single-target code, write
                                        // single target info too for the first, next, waypoint:
                                        if (wp_idx == wps.waypoint_index_current_goal)
                                        {
                                                nav_cmd.target = ti;
                                        }
                                        // Append to list of targets:
                                        nav_cmd.multiple_targets.emplace_back(ti);
                                }
                                this->processNavigateCommand(&nav_cmd);

                                MRPT_LOG_DEBUG_STREAM(
                                        "[CWaypointsNavigator::navigationStep] Active waypoint "
                                        "changed. Current status:\n"
                                        << this->getWaypointNavStatus().getAsText());
                        }
                }
        }

        // Note: navigationStep() called *after* waypoints part to get
        // end-of-navigation events *after*
        //       waypoints-related events:

        m_was_aligning = m_is_aligning;  // Let the next timestep know about this

        MRPT_END
}

void CWaypointsNavigator::navigationStep()
{
        MRPT_START
        m_is_aligning =
                false;  // the robot is aligning into a waypoint with a desired heading

        if (m_navigationState != SUSPENDED)
        {
                waypoints_navigationStep();
        }

        // Call base navigation step to execute one-single waypoint navigation, as
        // usual:
        if (!m_is_aligning)
        {
                CAbstractNavigator::navigationStep();  // This internally locks
                // "m_nav_cs"
        }
        else
        {
                // otherwise, at least, process pending events:
                CAbstractNavigator::dispatchPendingNavEvents();
        }

        MRPT_END
}

/** \callergraph */
void CWaypointsNavigator::onStartNewNavigation() {}
/** \callergraph */
bool CWaypointsNavigator::isRelativePointReachable(
        const mrpt::math::TPoint2D& wp_local_wrt_robot) const
{
        return impl_waypoint_is_reachable(wp_local_wrt_robot);
}

void CWaypointsNavigator::loadConfigFile(const mrpt::utils::CConfigFileBase& c)
{
        MRPT_START

        params_waypoints_navigator.loadFromConfigFile(c, "CWaypointsNavigator");
        CAbstractNavigator::loadConfigFile(c);

        MRPT_END
}

void CWaypointsNavigator::saveConfigFile(mrpt::utils::CConfigFileBase& c) const
{
        CAbstractNavigator::saveConfigFile(c);
        params_waypoints_navigator.saveToConfigFile(c, "CWaypointsNavigator");
}

void mrpt::nav::CWaypointsNavigator::TWaypointsNavigatorParams::
	loadFromConfigFile(
                const mrpt::utils::CConfigFileBase& c, const std::string& s)
{
        MRPT_LOAD_CONFIG_VAR(max_distance_to_allow_skip_waypoint, double, c, s);
        MRPT_LOAD_CONFIG_VAR(min_timesteps_confirm_skip_waypoints, int, c, s);
        MRPT_LOAD_CONFIG_VAR_DEGREES(waypoint_angle_tolerance, c, s);
        MRPT_LOAD_CONFIG_VAR(rel_speed_for_stop_waypoints, double, c, s);
        MRPT_LOAD_CONFIG_VAR(multitarget_look_ahead, int, c, s);
}

void mrpt::nav::CWaypointsNavigator::TWaypointsNavigatorParams::
	saveToConfigFile(
                mrpt::utils::CConfigFileBase& c, const std::string& s) const
{
        MRPT_SAVE_CONFIG_VAR_COMMENT(
                max_distance_to_allow_skip_waypoint,
                "Max distance to `foresee` waypoints [meters]. (<0: unlimited)");
        MRPT_SAVE_CONFIG_VAR_COMMENT(
                min_timesteps_confirm_skip_waypoints,
                "Min timesteps a `future` waypoint must be seen as reachable to become "
                "the active one.");
        MRPT_SAVE_CONFIG_VAR_DEGREES_COMMENT(
                "waypoint_angle_tolerance", waypoint_angle_tolerance,
                "Angular error tolerance for waypoints with an assigned heading [deg] "
                "(Default: 5 deg)");
        MRPT_SAVE_CONFIG_VAR_COMMENT(
                rel_speed_for_stop_waypoints,
                "[0,1] Relative speed when aiming at a stop-point waypoint "
                "(Default=0.10)");
        MRPT_SAVE_CONFIG_VAR_COMMENT(
                multitarget_look_ahead,
                ">=0 number of waypoints to forward to the underlying navigation "
                "engine, to ease obstacles avoidance when a waypoint is blocked "
                "(Default=0 : none)");
}

CWaypointsNavigator::TWaypointsNavigatorParams::TWaypointsNavigatorParams()
        : max_distance_to_allow_skip_waypoint(-1.0),
          min_timesteps_confirm_skip_waypoints(1),
          waypoint_angle_tolerance(mrpt::utils::DEG2RAD(5.0)),
          rel_speed_for_stop_waypoints(0.10),
          multitarget_look_ahead(0)
{
}

/** \callergraph */
bool CWaypointsNavigator::checkHasReachedTarget(const double targetDist) const
{
        bool ret;
        const TWaypointStatus* wp = nullptr;
        const auto& wps = m_waypoint_nav_status;
        if (m_navigationParams->target.targetIsIntermediaryWaypoint)
        {
                ret = false;
        }
        else if (wps.timestamp_nav_started != INVALID_TIMESTAMP)
        {
                wp = (!wps.waypoints.empty() && wps.waypoint_index_current_goal >= 0 &&
                          wps.waypoint_index_current_goal < (int)wps.waypoints.size())
                                 ? &wps.waypoints[wps.waypoint_index_current_goal]
                                 : nullptr;
                ret =
                        (wp == nullptr &&
                         targetDist <= m_navigationParams->target.targetAllowedDistance) ||
                        (wp->reached);
        }
        else
        {
                ret = (targetDist <= m_navigationParams->target.targetAllowedDistance);
        }
        MRPT_LOG_DEBUG_STREAM(
                "CWaypointsNavigator::checkHasReachedTarget() called "
                "with targetDist="
                << targetDist << " return=" << ret
                << " waypoint: " << (wp == nullptr ? std::string("") : wp->getAsText())
                << "wps.timestamp_nav_started="
                << (wps.timestamp_nav_started == INVALID_TIMESTAMP
                                ? "INVALID_TIMESTAMP"
                                : mrpt::system::dateTimeLocalToString(
                                          wps.timestamp_nav_started)));
        return ret;
}