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root / scout / libscout / src / behaviors / line_follow.cpp @ 6fab3966

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/**
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 * Copyright (c) 2011 Colony Project
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 * 
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 * Permission is hereby granted, free of charge, to any person
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 * obtaining a copy of this software and associated documentation
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 * files (the "Software"), to deal in the Software without
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 * restriction, including without limitation the rights to use,
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 * copy, modify, merge, publish, distribute, sublicense, and/or sell
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 * copies of the Software, and to permit persons to whom the
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 * Software is furnished to do so, subject to the following
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 * conditions:
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 * 
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 * The above copyright notice and this permission notice shall be
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 * included in all copies or substantial portions of the Software.
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 * 
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 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
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 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
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 * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
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 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
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 * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
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 * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
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 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
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 * OTHER DEALINGS IN THE SOFTWARE.
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 */
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#include "line_follow.h"
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using namespace std;
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static int motor_l;
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static int motor_r;
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Duration init_turn_time(0.5);
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void line_follow::follow_line()
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{
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    do
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    {
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        double line_loc = linesensor->readline();
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        ROS_INFO("Line location: %lf.\n", line_loc);
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        motor_l = min(max((int) (-MOTOR_BASE + SCALE * line_loc), -128), 127);
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        motor_r = min(max((int) (-MOTOR_BASE - SCALE * line_loc), -128), 127);
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        motors->set_sides(motor_l, motor_r, MOTOR_ABSOLUTE);
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    }
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    while(!linesensor->fullline());
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    halt();
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    ROS_INFO("Intersection reached!");
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}
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void line_follow::turn_straight()
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{
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  do
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  {
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    motor_l = -MOTOR_BASE;
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    motor_r = -MOTOR_BASE;
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    motors->set_sides(motor_l, motor_r, MOTOR_ABSOLUTE);
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  }
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  while(linesensor->fullline());
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}
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void line_follow::turn_left()
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{
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  bool first = true;
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  float line_loc;
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  do
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  {
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    motor_l = -MOTOR_BASE;
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    motor_r = MOTOR_BASE/8;
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    motors->set_sides(motor_l, motor_r, MOTOR_ABSOLUTE);
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    if(first)
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    {
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        init_turn_time.sleep();
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        first = false;
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    }
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    line_loc = linesensor->readline();
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  }
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  while(!(-1 < line_loc && line_loc < 1));
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}
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void line_follow::halt()
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{
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    motors->set_sides(0, 0, MOTOR_ABSOLUTE);
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}
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void line_follow::spot_turn()
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{
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  bool first = true;
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  float line_loc;
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  do
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  {
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    motor_l = MOTOR_BASE;
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    motor_r = -MOTOR_BASE;
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    motors->set_sides(motor_l, motor_r, MOTOR_ABSOLUTE);
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    if(first)
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    {
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        while(line_loc < 2 && line_loc > -2)
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          line_loc = linesensor->readline();
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        first = false;
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    }
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    line_loc = linesensor->readline();
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  }
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  while(!(-1 < line_loc && line_loc < 1));
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}
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void line_follow::turn_right()
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{
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  bool first = true;
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  float line_loc;
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  do
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  {
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    motor_l = MOTOR_BASE/8;
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    motor_r = -MOTOR_BASE;
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    motors->set_sides(motor_l, motor_r, MOTOR_ABSOLUTE);
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    if(first)
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    {
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        init_turn_time.sleep();
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        first = false;
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    }
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    line_loc = linesensor->readline();
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  }
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  while(!(-1 < line_loc && line_loc < 1));
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}
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void line_follow::u_turn()
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{
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  turn_right();
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  follow_line();
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  turn_right();
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}
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void line_follow::run()
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{
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  while(ok())
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  {
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    follow_line();
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  }
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}