ArActionAvoidSide.cpp

/*
MobileRobots Advanced Robotics Interface for Applications (ARIA)
Copyright (C) 2004, 2005 ActivMedia Robotics LLC
Copyright (C) 2006, 2007 MobileRobots Inc.

     This program is free software; you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
     the Free Software Foundation; either version 2 of the License, or
     (at your option) any later version.

     This program is distributed in the hope that it will be useful,
     but WITHOUT ANY WARRANTY; without even the implied warranty of
     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
     GNU General Public License for more details.

     You should have received a copy of the GNU General Public License
     along with this program; if not, write to the Free Software
     Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

If you wish to redistribute ARIA under different terms, contact 
MobileRobots for information about a commercial version of ARIA at 
robots@mobilerobots.com or 
MobileRobots Inc, 19 Columbia Drive, Amherst, NH 03031; 800-639-9481
*/

#include "ArExport.h"
#include "ariaOSDef.h"
#include "ArActionAvoidSide.h"
#include "ArRobot.h"

AREXPORT ArActionAvoidSide::ArActionAvoidSide(const char *name,
                          double obstacleDistance,
                          double turnAmount) :
  ArAction(name, "Avoids side obstacles, ie walls")
{
  setNextArgument(ArArg("obstacle distance", &myObsDist, 
            "Distance at which to start avoiding (mm)"));
  myObsDist = obstacleDistance;
  setNextArgument(ArArg("turn amount", &myTurnAmount,
            "Degrees at which to turn (deg)"));
  myTurnAmount = turnAmount;

  myTurning = false;

}

AREXPORT ArActionAvoidSide::~ArActionAvoidSide()
{

}

AREXPORT ArActionDesired *ArActionAvoidSide::fire(
    ArActionDesired currentDesired)
{
  double leftDist, rightDist;

  leftDist = (myRobot->checkRangeDevicesCurrentPolar(60, 120) - 
          myRobot->getRobotRadius());
  rightDist = (myRobot->checkRangeDevicesCurrentPolar(-120, -60) - 
          myRobot->getRobotRadius());
  
  myDesired.reset();
  if (leftDist < myObsDist)
  {
    myDesired.setDeltaHeading(-myTurnAmount);
    myDesired.setVel(0);
    myTurning = true;
  }
  else if (rightDist < myObsDist)
  {
    myDesired.setDeltaHeading(myTurnAmount);
    myDesired.setVel(0);
    myTurning = true;
  }
  else if (myTurning)
    myDesired.setDeltaHeading(0);

  return &myDesired;
}

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