velocityprofile_trap.cpp

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/***************************************************************************
  tag: Erwin Aertbelien  Mon May 10 19:10:36 CEST 2004  velocityprofile_trap.cxx

                        velocityprofile_trap.cxx -  description
                           -------------------
    begin                : Mon May 10 2004
    copyright            : (C) 2004 Erwin Aertbelien
    email                : erwin.aertbelien@mech.kuleuven.ac.be

 ***************************************************************************
 *   This library is free software; you can redistribute it and/or         *
 *   modify it under the terms of the GNU Lesser General Public            *
 *   License as published by the Free Software Foundation; either          *
 *   version 2.1 of the License, or (at your option) any later version.    *
 *                                                                         *
 *   This library 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     *
 *   Lesser General Public License for more details.                       *
 *                                                                         *
 *   You should have received a copy of the GNU Lesser General Public      *
 *   License along with this library; if not, write to the Free Software   *
 *   Foundation, Inc., 59 Temple Place,                                    *
 *   Suite 330, Boston, MA  02111-1307  USA                                *
 *                                                                         *
 ***************************************************************************/
/*****************************************************************************
 *  \author
 *      Erwin Aertbelien, Div. PMA, Dep. of Mech. Eng., K.U.Leuven
 *
 *  \version
 *              ORO_Geometry V0.2
 *
 *      \par History
 *              - $log$
 *
 *      \par Release
 *              $Id: velocityprofile_trap.cpp,v 1.1.1.1.2.7 2003/07/24 13:26:15 psoetens Exp $
 *              $Name:  $
 ****************************************************************************/


//#include "error.h"
#include "velocityprofile_trap.hpp"

namespace KDL {


VelocityProfile_Trap::VelocityProfile_Trap(double _maxvel,double _maxacc):
          a1(0), a2(0), a3(0),
          b1(0), b2(0), b3(0),
          c1(0), c2(0), c3(0),
          duration(0), t1(0), t2(0),
                  maxvel(_maxvel),maxacc(_maxacc),
          startpos(0), endpos(0)

{}
                // constructs motion profile class with <maxvel> as parameter of the
                // trajectory.

void VelocityProfile_Trap::SetProfile(double pos1,double pos2) {
        startpos = pos1;
        endpos   = pos2;
        t1 = maxvel/maxacc;
        double s       = sign(endpos-startpos);
        double deltax1 = s*maxacc*sqr(t1)/2.0;
        double deltaT  = (endpos-startpos-2.0*deltax1) / (s*maxvel);
        if (deltaT > 0.0) {
                // plan a complete profile :
                duration = 2*t1+deltaT;
                t2 = duration - t1;
        } else {
                // plan an incomplete profile :
                t1 = ::sqrt((endpos-startpos)/s/maxacc);
                duration = t1*2.0;
                t2=t1;
        }
        a3 = s*maxacc/2.0;
        a2 = 0;
        a1 = startpos;

        b3 = 0;
        b2 = a2+2*a3*t1 - 2.0*b3*t1;
        b1 = a1+t1*(a2+a3*t1) - t1*(b2+t1*b3);

        c3 = -s*maxacc/2.0;
        c2 = b2+2*b3*t2 - 2.0*c3*t2;
        c1 = b1+t2*(b2+b3*t2) - t2*(c2+t2*c3);
}

void VelocityProfile_Trap::SetProfileDuration(
        double pos1,double pos2,double newduration) {
        // duration should be longer than originally planned duration
        // Fastest :
        SetProfile(pos1,pos2);
        // Must be Slower  :
        double factor = duration/newduration;
        if (factor > 1)
                return; // do not exceed max
        a2*=factor;
        a3*=factor*factor;
        b2*=factor;
        b3*=factor*factor;
        c2*=factor;
        c3*=factor*factor;
        duration = newduration;
        t1 /= factor;
        t2 /= factor;
}

void VelocityProfile_Trap::SetProfileVelocity(
        double pos1,double pos2,double newvelocity) {
        // Max velocity
        SetProfile(pos1,pos2);
        // Must be Slower  :
        double factor = newvelocity;            // valid = [KDL::epsilon, 1.0]
        if (1.0 < factor) factor = 1.0;
        if (KDL::epsilon > factor) factor = KDL::epsilon;
        a2*=factor;
        a3*=factor*factor;
        b2*=factor;
        b3*=factor*factor;
        c2*=factor;
        c3*=factor*factor;
        duration = duration / factor;
        t1 /= factor;
        t2 /= factor;
}

void VelocityProfile_Trap::SetMax(double _maxvel,double _maxacc)
{
        maxvel = _maxvel; maxacc = _maxacc;
}

double VelocityProfile_Trap::Duration() const {
        return duration;
}

double VelocityProfile_Trap::Pos(double time) const {
        if (time < 0) {
                return startpos;
        } else if (time<t1) {
                return a1+time*(a2+a3*time);
        } else if (time<t2) {
                return b1+time*(b2+b3*time);
        } else if (time<=duration) {
                return c1+time*(c2+c3*time);
        } else {
                return endpos;
        }
}
double VelocityProfile_Trap::Vel(double time) const {
        if (time < 0) {
                return 0;
        } else if (time<t1) {
                return a2+2*a3*time;
        } else if (time<t2) {
                return b2+2*b3*time;
        } else if (time<=duration) {
                return c2+2*c3*time;
        } else {
                return 0;
        }
}

double VelocityProfile_Trap::Acc(double time) const {
        if (time < 0) {
                return 0;
        } else if (time<t1) {
                return 2*a3;
        } else if (time<t2) {
                return 2*b3;
        } else if (time<=duration) {
                return 2*c3;
        } else {
                return 0;
        }
}

VelocityProfile* VelocityProfile_Trap::Clone() const {
        VelocityProfile_Trap* res =  new VelocityProfile_Trap(maxvel,maxacc);
        res->SetProfileDuration( this->startpos, this->endpos, this->duration );
        return res;
}

VelocityProfile_Trap::~VelocityProfile_Trap() {}


void VelocityProfile_Trap::Write(std::ostream& os) const {
        os << "TRAPEZOIDAL[" << maxvel << "," << maxacc <<"]";
}





}