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 <<"]";
}
 
 
 
 
 
}