rotate_recovery.cpp
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00001 /*********************************************************************
00002 *
00003 * Software License Agreement (BSD License)
00004 *
00005 *  Copyright (c) 2009, Willow Garage, Inc.
00006 *  All rights reserved.
00007 *
00008 *  Redistribution and use in source and binary forms, with or without
00009 *  modification, are permitted provided that the following conditions
00010 *  are met:
00011 *
00012 *   * Redistributions of source code must retain the above copyright
00013 *     notice, this list of conditions and the following disclaimer.
00014 *   * Redistributions in binary form must reproduce the above
00015 *     copyright notice, this list of conditions and the following
00016 *     disclaimer in the documentation and/or other materials provided
00017 *     with the distribution.
00018 *   * Neither the name of Willow Garage, Inc. nor the names of its
00019 *     contributors may be used to endorse or promote products derived
00020 *     from this software without specific prior written permission.
00021 *
00022 *  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
00023 *  "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
00024 *  LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
00025 *  FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
00026 *  COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
00027 *  INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
00028 *  BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
00029 *  LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
00030 *  CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
00031 *  LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
00032 *  ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
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00034 *
00035 * Author: Eitan Marder-Eppstein
00036 *********************************************************************/
00037 #include <rotate_recovery/rotate_recovery.h>
00038 #include <pluginlib/class_list_macros.h>
00039 
00040 //register this planner as a RecoveryBehavior plugin
00041 PLUGINLIB_DECLARE_CLASS(rotate_recovery, RotateRecovery, rotate_recovery::RotateRecovery, nav_core::RecoveryBehavior)
00042 
00043 namespace rotate_recovery {
00044 RotateRecovery::RotateRecovery(): global_costmap_(NULL), local_costmap_(NULL), 
00045   tf_(NULL), initialized_(false), world_model_(NULL) {} 
00046 
00047 void RotateRecovery::initialize(std::string name, tf::TransformListener* tf,
00048     costmap_2d::Costmap2DROS* global_costmap, costmap_2d::Costmap2DROS* local_costmap){
00049   if(!initialized_){
00050     name_ = name;
00051     tf_ = tf;
00052     global_costmap_ = global_costmap;
00053     local_costmap_ = local_costmap;
00054 
00055     //get some parameters from the parameter server
00056     ros::NodeHandle private_nh("~/" + name_);
00057     ros::NodeHandle blp_nh("~/TrajectoryPlannerROS");
00058 
00059     //we'll simulate every degree by default
00060     private_nh.param("sim_granularity", sim_granularity_, 0.017);
00061     private_nh.param("frequency", frequency_, 20.0);
00062 
00063     blp_nh.param("acc_lim_th", acc_lim_th_, 3.2);
00064     blp_nh.param("max_rotational_vel", max_rotational_vel_, 1.0);
00065     blp_nh.param("min_in_place_rotational_vel", min_rotational_vel_, 0.4);
00066     blp_nh.param("yaw_goal_tolerance", tolerance_, 0.10);
00067 
00068     world_model_ = new base_local_planner::CostmapModel(*local_costmap_->getCostmap());
00069 
00070     initialized_ = true;
00071   }
00072   else{
00073     ROS_ERROR("You should not call initialize twice on this object, doing nothing");
00074   }
00075 }
00076 
00077 RotateRecovery::~RotateRecovery(){
00078   delete world_model_;
00079 }
00080 
00081 void RotateRecovery::runBehavior(){
00082   if(!initialized_){
00083     ROS_ERROR("This object must be initialized before runBehavior is called");
00084     return;
00085   }
00086 
00087   if(global_costmap_ == NULL || local_costmap_ == NULL){
00088     ROS_ERROR("The costmaps passed to the RotateRecovery object cannot be NULL. Doing nothing.");
00089     return;
00090   }
00091   ROS_WARN("Rotate recovery behavior started.");
00092 
00093   ros::Rate r(frequency_);
00094   ros::NodeHandle n;
00095   ros::Publisher vel_pub = n.advertise<geometry_msgs::Twist>("cmd_vel", 10);
00096 
00097   tf::Stamped<tf::Pose> global_pose;
00098   local_costmap_->getRobotPose(global_pose);
00099 
00100   double current_angle = -1.0 * M_PI;
00101 
00102   bool got_180 = false;
00103 
00104   double start_offset = 0 - angles::normalize_angle(tf::getYaw(global_pose.getRotation()));
00105   while(n.ok()){
00106     local_costmap_->getRobotPose(global_pose);
00107 
00108     double norm_angle = angles::normalize_angle(tf::getYaw(global_pose.getRotation()));
00109     current_angle = angles::normalize_angle(norm_angle + start_offset);
00110 
00111     //compute the distance left to rotate
00112     double dist_left = M_PI - current_angle;
00113 
00114     double x = global_pose.getOrigin().x(), y = global_pose.getOrigin().y();
00115 
00116     //check if that velocity is legal by forward simulating
00117     double sim_angle = 0.0;
00118     while(sim_angle < dist_left){
00119       double theta = tf::getYaw(global_pose.getRotation()) + sim_angle;
00120 
00121       //make sure that the point is legal, if it isn't... we'll abort
00122       double footprint_cost = world_model_->footprintCost(x, y, theta, local_costmap_->getRobotFootprint(), 0.0, 0.0);
00123       if(footprint_cost < 0.0){
00124         ROS_ERROR("Rotate recovery can't rotate in place because there is a potential collision. Cost: %.2f", footprint_cost);
00125         return;
00126       }
00127 
00128       sim_angle += sim_granularity_;
00129     }
00130 
00131     //compute the velocity that will let us stop by the time we reach the goal
00132     double vel = sqrt(2 * acc_lim_th_ * dist_left);
00133 
00134     //make sure that this velocity falls within the specified limits
00135     vel = std::min(std::max(vel, min_rotational_vel_), max_rotational_vel_);
00136 
00137     geometry_msgs::Twist cmd_vel;
00138     cmd_vel.linear.x = 0.0;
00139     cmd_vel.linear.y = 0.0;
00140     cmd_vel.angular.z = vel;
00141 
00142     vel_pub.publish(cmd_vel);
00143 
00144     //makes sure that we won't decide we're done right after we start
00145     if(current_angle < 0.0)
00146       got_180 = true;
00147 
00148     //if we're done with our in-place rotation... then return
00149     if(got_180 && current_angle >= (0.0 - tolerance_))
00150       return;
00151 
00152     r.sleep();
00153   }
00154 }
00155 };


rotate_recovery
Author(s): Eitan Marder-Eppstein, contradict@gmail.com
autogenerated on Wed Aug 2 2017 03:13:20