blender/intern/itasc/kdl/chainjnttojacsolver.cpp
2011-02-25 11:45:16 +00:00

84 lines
2.8 KiB
C++

/** \file itasc/kdl/chainjnttojacsolver.cpp
* \ingroup itasc
*/
// Copyright (C) 2007 Ruben Smits <ruben dot smits at mech dot kuleuven dot be>
// Version: 1.0
// Author: Ruben Smits <ruben dot smits at mech dot kuleuven dot be>
// Maintainer: Ruben Smits <ruben dot smits at mech dot kuleuven dot be>
// URL: http://www.orocos.org/kdl
// 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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
#include "chainjnttojacsolver.hpp"
namespace KDL
{
ChainJntToJacSolver::ChainJntToJacSolver(const Chain& _chain):
chain(_chain)
{
}
ChainJntToJacSolver::~ChainJntToJacSolver()
{
}
int ChainJntToJacSolver::JntToJac(const JntArray& q_in,Jacobian& jac)
{
assert(q_in.rows()==chain.getNrOfJoints()&&
q_in.rows()==jac.columns());
Frame T_local, T_joint;
T_total = Frame::Identity();
SetToZero(t_local);
int i=chain.getNrOfSegments()-1;
unsigned int q_nr = chain.getNrOfJoints();
//Lets recursively iterate until we are in the root segment
while (i >= 0) {
const Segment& segment = chain.getSegment(i);
int ndof = segment.getJoint().getNDof();
q_nr -= ndof;
//get the pose of the joint.
T_joint = segment.getJoint().pose(((JntArray&)q_in)(q_nr));
// combine with the tip to have the tip pose
T_local = T_joint*segment.getFrameToTip();
//calculate new T_end:
T_total = T_local * T_total;
for (int dof=0; dof<ndof; dof++) {
// combine joint rotation with tip position to get a reference frame for the joint
T_joint.p = T_local.p;
// in which the twist can be computed (needed for NDof joint)
t_local = segment.twist(T_joint, 1.0, dof);
//transform the endpoint of the local twist to the global endpoint:
t_local = t_local.RefPoint(T_total.p - T_local.p);
//transform the base of the twist to the endpoint
t_local = T_total.M.Inverse(t_local);
//store the twist in the jacobian:
jac.twists[q_nr+dof] = t_local;
}
i--;
}//endwhile
//Change the base of the complete jacobian from the endpoint to the base
changeBase(jac, T_total.M, jac);
return 0;
}
}