ftc_planner.cpp

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#include <ros/ros.h>

#include <ftc_local_planner/ftc_planner.h>

#include <pluginlib/class_list_macros.h>

PLUGINLIB_EXPORT_CLASS(ftc_local_planner::FTCPlanner, nav_core::BaseLocalPlanner)

namespace ftc_local_planner
{

    FTCPlanner::FTCPlanner()
    {
    }

    void FTCPlanner::initialize(std::string name, tf::TransformListener* tf, costmap_2d::Costmap2DROS* costmap_ros)
    {
        ros::NodeHandle private_nh("~/" + name);
        local_plan_publisher_ = private_nh.advertise<nav_msgs::Path>("local_plan", 1);
        costmap_ros_ = costmap_ros;
        tf_ = tf;
        first_setPlan_ = true;
        rotate_to_global_plan_ = false;
        goal_reached_ = false;
        stand_at_goal_ = false;
        cmd_vel_angular_z_rotate_ = 0;
        cmd_vel_linear_x_ = 0;
        cmd_vel_angular_z_ = 0;

        //Parameter for dynamic reconfigure
        dsrv_ = new dynamic_reconfigure::Server<FTCPlannerConfig>(private_nh);
        dynamic_reconfigure::Server<FTCPlannerConfig>::CallbackType cb = boost::bind(&FTCPlanner::reconfigureCB, this, _1, _2);
        dsrv_->setCallback(cb);

        joinCostmap_ = new JoinCostmap();

        ROS_INFO("FTCPlanner: Version 2 Init.");
    }

    void FTCPlanner::reconfigureCB(FTCPlannerConfig &config, uint32_t level)
    {
        if (config.restore_defaults)
        {
            config = default_config_;
            config.restore_defaults = false;
        }
        config_ = config;
    }

    bool FTCPlanner::setPlan(const std::vector<geometry_msgs::PoseStamped>& plan)
    {
        global_plan_ = plan;

        //First start of the local plan. First global plan.
        bool first_use = false;
        if(first_setPlan_)
        {
            if(config_.join_obstacle){
                //init joincostmap with local an global costmap.
                joinCostmap_->initialize(costmap_ros_, global_costmap_ros_);
            }

            first_setPlan_ = false;
            ftc_local_planner::getXPose(*tf_,global_plan_, costmap_ros_->getGlobalFrameID(),old_goal_pose_,global_plan_.size()-1);
            first_use = true;
        }

        ftc_local_planner::getXPose(*tf_,global_plan_, costmap_ros_->getGlobalFrameID(),goal_pose_,global_plan_.size()-1);
        //Have the new global plan an new goal, reset. Else dont reset.
        if(std::abs(std::abs(old_goal_pose_.getOrigin().getX())-std::abs(goal_pose_.getOrigin().getX())) <= config_.position_accuracy &&
                std::abs(std::abs(old_goal_pose_.getOrigin().getY())-std::abs(goal_pose_.getOrigin().getY())) <= config_.position_accuracy && !first_use
                && std::abs(angles::shortest_angular_distance(tf::getYaw(old_goal_pose_.getRotation()), tf::getYaw(goal_pose_.getRotation()))) <= config_.rotation_accuracy)
        {
            ROS_DEBUG("FTCPlanner: Old Goal == new Goal.");
        }
        else
        {
            //Rotate to first global plan point.
            rotate_to_global_plan_ = true;
            goal_reached_ = false;
            stand_at_goal_ = false;
            ROS_INFO("FTCPlanner: New Goal. Start new routine.");
        }

        old_goal_pose_ = goal_pose_;

        return true;
    }

    bool FTCPlanner::computeVelocityCommands(geometry_msgs::Twist& cmd_vel)
    {

        ros::Time begin = ros::Time::now();

        tf::Stamped<tf::Pose> current_pose;
        costmap_ros_->getRobotPose(current_pose);

        //Join the actual global an local costmap in the global costmap.
        if(config_.join_obstacle){
            joinCostmap_->joinMaps();
        }
        int max_point = 0;
        //First part of the routine. Rotatio to the first global plan orientation.
        if(rotate_to_global_plan_)
        {
            double angle_to_global_plan = calculateGlobalPlanAngle(current_pose, global_plan_, checkMaxDistance(current_pose));
            rotate_to_global_plan_ = rotateToOrientation(angle_to_global_plan, cmd_vel, 0.1);
        }
        //Second part of the routine. Drive alonge the global plan.
        else
        {

            double distance = sqrt(pow((goal_pose_.getOrigin().getX()-current_pose.getOrigin().getX()),2)+pow((goal_pose_.getOrigin().getY()-current_pose.getOrigin().getY()),2));

            //Check if robot near enough to global goal.
            if(distance > config_.position_accuracy && !stand_at_goal_)
            {

                if(fabs(calculateGlobalPlanAngle(current_pose, global_plan_, checkMaxDistance(current_pose)) > 1.2))
                {
                    ROS_INFO("FTCPlanner: Excessive deviation from global plan orientation. Start routine new.");
                    rotate_to_global_plan_ = true;
                }

                max_point = driveToward(current_pose, cmd_vel);

                if(!checkCollision(max_point))
                {
                    return false;
                }
            }
            //Third part of the routine. Rotate at goal to goal orientation.
            else
            {
                if(!stand_at_goal_)
                {
                    ROS_INFO("FTCPlanner: Stand at goal. Rotate to goal orientation.");
                }
                stand_at_goal_ = true;


                //Get the goal orientation.
                double angle_to_global_plan = angles::shortest_angular_distance(tf::getYaw(current_pose.getRotation()), tf::getYaw(goal_pose_.getRotation()));
                //Rotate until goalorientation is reached.
                if(!rotateToOrientation(angle_to_global_plan, cmd_vel, config_.rotation_accuracy))
                {
                    goal_reached_ = true;
                }
                cmd_vel.linear.x = 0;
                cmd_vel.linear.y = 0;
            }
        }

        publishPlan(max_point);

        ros::Time end = ros::Time::now();
        ros::Duration duration = end - begin;
        ROS_DEBUG("FTCPlanner: Calculation time: %f seconds", duration.toSec());
        return true;
    }

    int FTCPlanner::checkMaxDistance(tf::Stamped<tf::Pose> current_pose)
    {
        int max_point = 0;
        tf::Stamped<tf::Pose> x_pose;
        transformed_global_plan_.clear();
        for (unsigned int i = 0; i < global_plan_.size(); i++)
        {
            ftc_local_planner::getXPose(*tf_,global_plan_, costmap_ros_->getGlobalFrameID(),x_pose,i);
            double distance = sqrt(pow((x_pose.getOrigin().getX()-current_pose.getOrigin().getX()),2)+pow((x_pose.getOrigin().getY()-current_pose.getOrigin().getY()),2));

            tf::Stamped<tf::Pose> p = tf::Stamped<tf::Pose>(x_pose,
                                      ros::Time::now(),
                                      costmap_ros_->getGlobalFrameID());
            geometry_msgs::PoseStamped pose;
            tf::poseStampedTFToMsg(p, pose);
            transformed_global_plan_.push_back(pose);

            max_point = i-1;
            //If distance higher than maximal moveable distance in sim_time.
            if(distance > (config_.max_x_vel*config_.sim_time))
            {
                break;
            }
        }
        if(max_point < 0)
        {
            max_point = 0;
        }
        return max_point;
    }

    int FTCPlanner::checkMaxAngle(int points, tf::Stamped<tf::Pose> current_pose)
    {
        int max_point = points;
        double angle = 0;
        for(int i = max_point; i >= 0; i--)
        {
            angle = calculateGlobalPlanAngle(current_pose, global_plan_, i);

            max_point = i;
            //check if the angle is moveable
            if(fabs(angle) < config_.max_rotation_vel*config_.sim_time)
            {
                break;
            }
        }
        return max_point;
    }

    double FTCPlanner::calculateGlobalPlanAngle(tf::Stamped<tf::Pose> current_pose, const std::vector<geometry_msgs::PoseStamped>& plan, int point)
    {
        if(point >= (int)plan.size())
        {
            point = plan.size()-1;
        }
        double angle = 0;
        double current_th = tf::getYaw(current_pose.getRotation());
        for(int i = 0; i <= point; i++)
        {
            geometry_msgs::PoseStamped x_pose;
            x_pose=transformed_global_plan_.at(i);

            //Calculate the angles between robotpose and global plan point pose
            double angle_to_goal = atan2(x_pose.pose.position.y - current_pose.getOrigin().getY(),
                                         x_pose.pose.position.x - current_pose.getOrigin().getX());
            angle += angle_to_goal;
        }

        //average
        angle = angle/(point+1);

        return angles::shortest_angular_distance(current_th, angle);
    }

    bool FTCPlanner::rotateToOrientation(double angle, geometry_msgs::Twist& cmd_vel, double accuracy)
    {

        if((cmd_vel_linear_x_  - 0.1)  >= 0){
            cmd_vel.linear.x = cmd_vel_linear_x_ - 0.1;
            cmd_vel_linear_x_ = cmd_vel_linear_x_ - 0.1;
        }
        if(fabs(angle) > accuracy)
        {
            //Slow down
            if(config_.max_rotation_vel >= fabs(angle) * (config_.acceleration_z+config_.slow_down_factor))
            {
                ROS_DEBUG("FTCPlanner: Slow down.");
                if(angle < 0)
                {
                    if(cmd_vel_angular_z_rotate_ >= -config_.min_rotation_vel)
                    {
                        cmd_vel_angular_z_rotate_ = - config_.min_rotation_vel;
                        cmd_vel.angular.z = cmd_vel_angular_z_rotate_;

                    }
                    else
                    {
                        cmd_vel_angular_z_rotate_ = cmd_vel_angular_z_rotate_ + config_.acceleration_z/config_.local_planner_frequence;
                        cmd_vel.angular.z = cmd_vel_angular_z_rotate_;
                    }
                }
                if(angle > 0)
                {
                    if(cmd_vel_angular_z_rotate_  <= config_.min_rotation_vel)
                    {
                        cmd_vel_angular_z_rotate_ =  config_.min_rotation_vel;
                        cmd_vel.angular.z = cmd_vel_angular_z_rotate_;

                    }
                    else
                    {
                        cmd_vel_angular_z_rotate_ = cmd_vel_angular_z_rotate_ - config_.acceleration_z/config_.local_planner_frequence;
                        cmd_vel.angular.z = cmd_vel_angular_z_rotate_;
                    }
                }
            }
            else
            {
                //Speed up
                if(fabs(cmd_vel_angular_z_rotate_) < config_.max_rotation_vel)
                {
                    ROS_DEBUG("FTCPlanner: Speeding up");
                    if(angle < 0)
                    {
                        cmd_vel_angular_z_rotate_ = cmd_vel_angular_z_rotate_ - config_.acceleration_z/config_.local_planner_frequence;

                        if(fabs(cmd_vel_angular_z_rotate_) > config_.max_rotation_vel)
                        {
                            cmd_vel_angular_z_rotate_ = - config_.max_rotation_vel;
                        }
                        cmd_vel.angular.z = cmd_vel_angular_z_rotate_;
                    }
                    if(angle > 0)
                    {
                        cmd_vel_angular_z_rotate_ = cmd_vel_angular_z_rotate_ + config_.acceleration_z/config_.local_planner_frequence;

                        if(fabs(cmd_vel_angular_z_rotate_) > config_.max_rotation_vel)
                        {
                            cmd_vel_angular_z_rotate_ = config_.max_rotation_vel;
                        }

                        cmd_vel.angular.z = cmd_vel_angular_z_rotate_;
                    }
                }
                else
                {
                    cmd_vel.angular.z = cmd_vel_angular_z_rotate_;
                }
            }
            ROS_DEBUG("FTCPlanner: cmd_vel.z: %f, angle: %f", cmd_vel.angular.z, angle);
            return true;
        }
        else
        {
            cmd_vel_angular_z_rotate_ = 0;
            cmd_vel.angular.z = 0;
            return false;
        }
    }

    int FTCPlanner::driveToward(tf::Stamped<tf::Pose> current_pose, geometry_msgs::Twist& cmd_vel)
    {
        double distance = 0;
        double angle = 0;
        int max_point = 0;

        //Search for max achievable point on global plan.
        max_point = checkMaxDistance(current_pose);
        max_point = checkMaxAngle(max_point, current_pose);


        double cmd_vel_linear_x_old = cmd_vel_linear_x_;
        double cmd_vel_angular_z_old = cmd_vel_angular_z_;

        geometry_msgs::PoseStamped x_pose;
        x_pose = transformed_global_plan_.at(max_point);

        distance = sqrt(pow((x_pose.pose.position.x-current_pose.getOrigin().getX()),2)+pow((x_pose.pose.position.y-current_pose.getOrigin().getY()),2));
        angle = calculateGlobalPlanAngle(current_pose, global_plan_, max_point);

        //check if max velocity is exceeded
        if((distance/config_.sim_time) > config_.max_x_vel)
        {
            cmd_vel_linear_x_ = config_.max_x_vel;
        }
        else
        {
            cmd_vel_linear_x_ = (distance/config_.sim_time);
        }

        //check if max rotation velocity is exceeded
        if(fabs(angle/config_.sim_time)>config_.max_rotation_vel)
        {
            cmd_vel_angular_z_ = config_.max_rotation_vel;
        }
        else
        {
            cmd_vel_angular_z_ = (angle/config_.sim_time);
        }

        //Calculate new velocity with max acceleration
        if(cmd_vel_linear_x_ > cmd_vel_linear_x_old+config_.acceleration_x/config_.local_planner_frequence)
        {
            cmd_vel_linear_x_ = cmd_vel_linear_x_old+config_.acceleration_x/config_.local_planner_frequence;
        }
        else
        {
            if(cmd_vel_linear_x_ < cmd_vel_linear_x_old-config_.acceleration_x/config_.local_planner_frequence)
            {
                cmd_vel_linear_x_ = cmd_vel_linear_x_old-config_.acceleration_x/config_.local_planner_frequence;
            }
            else
            {
                cmd_vel_linear_x_ = cmd_vel_linear_x_old;
            }
        }

        //Calculate new velocity with max acceleration
        if(fabs(cmd_vel_angular_z_) > fabs(cmd_vel_angular_z_old)+fabs(config_.acceleration_z/config_.local_planner_frequence))
        {
            if(cmd_vel_angular_z_ < 0)
            {
                cmd_vel_angular_z_ = cmd_vel_angular_z_old-config_.acceleration_z/config_.local_planner_frequence;
            }
            else
            {
                cmd_vel_angular_z_ = cmd_vel_angular_z_old+config_.acceleration_z/config_.local_planner_frequence;
            }
        }

        if(cmd_vel_angular_z_ < 0 && cmd_vel_angular_z_old > 0)
        {
            if( fabs(cmd_vel_angular_z_ - cmd_vel_angular_z_old) > fabs(config_.acceleration_z/config_.local_planner_frequence))
            {
                cmd_vel_angular_z_ = cmd_vel_angular_z_old - config_.acceleration_z/config_.local_planner_frequence;
            }
        }

        if(cmd_vel_angular_z_ > 0 && cmd_vel_angular_z_old < 0)
        {
            if( fabs(cmd_vel_angular_z_ - cmd_vel_angular_z_old) > fabs(config_.acceleration_z/config_.local_planner_frequence))
            {
                cmd_vel_angular_z_ = cmd_vel_angular_z_old + config_.acceleration_z/config_.local_planner_frequence;
            }
        }

        //Check at last if velocity is to high.
        if(cmd_vel_angular_z_ > config_.max_rotation_vel)
        {
            cmd_vel_angular_z_ = config_.max_rotation_vel;
        }
        if(cmd_vel_angular_z_ < -config_.max_rotation_vel)
        {
            cmd_vel_angular_z_ = (- config_.max_rotation_vel);
        }
        if(cmd_vel_linear_x_ >  config_.max_x_vel)
        {
            cmd_vel_linear_x_ = config_.max_x_vel;
        }
        //Push velocity to cmd_vel for driving.
        cmd_vel.linear.x = cmd_vel_linear_x_;
        cmd_vel.angular.z = cmd_vel_angular_z_;
        cmd_vel_angular_z_rotate_ = cmd_vel_angular_z_;
        ROS_DEBUG("FTCPlanner: max_point: %d, distance: %f, x_vel: %f, rot_vel: %f, angle: %f", max_point, distance, cmd_vel.linear.x, cmd_vel.angular.z, angle);

        return max_point;
    }


    bool FTCPlanner::isGoalReached()
    {
        if(goal_reached_)
        {
            ROS_INFO("FTCPlanner: Goal reached.");
        }
        return goal_reached_;
    }

    bool FTCPlanner::checkCollision(int max_points)
    {
        //maximal costs
        unsigned char previous_cost = 255;

        for (int i = 0; i <= max_points; i++)
        {
            geometry_msgs::PoseStamped x_pose;
            x_pose = transformed_global_plan_.at(i);

            unsigned int x;
            unsigned int y;
            costmap_ros_->getCostmap()->worldToMap(x_pose.pose.position.x, x_pose.pose.position.y, x, y);
            unsigned char costs = costmap_ros_->getCostmap()->getCost(x, y);
            //Near at obstacel
            if(costs > 0)
            {
                if(!rotate_to_global_plan_)
                {
                    ROS_INFO("FTCPlanner: Obstacel detected. Start routine new.");
                }
                rotate_to_global_plan_ = true;

                //Possible collision
                if(costs > 127 && costs > previous_cost)
                {
                    ROS_WARN("FTCPlanner: Possible collision. Stop local planner.");
                    return false;
                }
            }
            previous_cost = costs;
        }
        return true;
    }

    void FTCPlanner::publishPlan(int max_point)
    {
        std::vector<geometry_msgs::PoseStamped> path;
        path = transformed_global_plan_;

        //given an empty path we won't do anything
        if(path.empty())
            return;

        //create a path message
        nav_msgs::Path gui_path;
        gui_path.poses.resize(path.size());
        gui_path.header.frame_id = path[0].header.frame_id;
        gui_path.header.stamp = path[0].header.stamp;

        // Extract the plan in world co-ordinates, we assume the path is all in the same frame
        for(unsigned int i=0; i < path.size(); i++)
        {
            gui_path.poses[i] = path[i];
        }

        local_plan_publisher_.publish(gui_path);
    }

    FTCPlanner::~FTCPlanner()
    {
    }
}