kdl_tl.cpp

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#include <trac_ik/kdl_tl.hpp>
#include <boost/date_time.hpp>
#include <ros/ros.h>
#include <limits>

namespace KDL
{
ChainIkSolverPos_TL::ChainIkSolverPos_TL(const Chain& _chain, const JntArray& _q_min, const JntArray& _q_max, double _maxtime, double _eps, bool _random_restart, bool _try_jl_wrap):
  chain(_chain), q_min(_q_min), q_max(_q_max), vik_solver(_chain), fksolver(_chain), delta_q(_chain.getNrOfJoints()),
  maxtime(_maxtime), eps(_eps), rr(_random_restart), wrap(_try_jl_wrap)
{

  assert(chain.getNrOfJoints() == _q_min.data.size());
  assert(chain.getNrOfJoints() == _q_max.data.size());

  reset();

  for (uint i = 0; i < chain.segments.size(); i++)
  {
    std::string type = chain.segments[i].getJoint().getTypeName();
    if (type.find("Rot") != std::string::npos)
    {
      if (_q_max(types.size()) >= std::numeric_limits<float>::max() &&
          _q_min(types.size()) <= std::numeric_limits<float>::lowest())
        types.push_back(KDL::BasicJointType::Continuous);
      else types.push_back(KDL::BasicJointType::RotJoint);
    }
    else if (type.find("Trans") != std::string::npos)
      types.push_back(KDL::BasicJointType::TransJoint);

  }

  assert(types.size() == _q_max.data.size());
}



int ChainIkSolverPos_TL::CartToJnt(const KDL::JntArray &q_init, const KDL::Frame &p_in, KDL::JntArray &q_out, const KDL::Twist _bounds)
{

  if (aborted)
    return -3;

  boost::posix_time::ptime start_time = boost::posix_time::microsec_clock::local_time();
  boost::posix_time::time_duration timediff;
  q_out = q_init;
  bounds = _bounds;


  double time_left;

  do
  {
    fksolver.JntToCart(q_out, f);
    delta_twist = diffRelative(p_in, f);

    if (std::abs(delta_twist.vel.x()) <= std::abs(bounds.vel.x()))
      delta_twist.vel.x(0);

    if (std::abs(delta_twist.vel.y()) <= std::abs(bounds.vel.y()))
      delta_twist.vel.y(0);

    if (std::abs(delta_twist.vel.z()) <= std::abs(bounds.vel.z()))
      delta_twist.vel.z(0);

    if (std::abs(delta_twist.rot.x()) <= std::abs(bounds.rot.x()))
      delta_twist.rot.x(0);

    if (std::abs(delta_twist.rot.y()) <= std::abs(bounds.rot.y()))
      delta_twist.rot.y(0);

    if (std::abs(delta_twist.rot.z()) <= std::abs(bounds.rot.z()))
      delta_twist.rot.z(0);

    if (Equal(delta_twist, Twist::Zero(), eps))
      return 1;

    delta_twist = diff(f, p_in);

    vik_solver.CartToJnt(q_out, delta_twist, delta_q);
    KDL::JntArray q_curr;

    Add(q_out, delta_q, q_curr);

    for (unsigned int j = 0; j < q_min.data.size(); j++)
    {
      if (types[j] == KDL::BasicJointType::Continuous)
        continue;
      if (q_curr(j) < q_min(j))
      {
        if (!wrap || types[j] == KDL::BasicJointType::TransJoint)
          // KDL's default
          q_curr(j) = q_min(j);
        else
        {
          // Find actual wrapped angle between limit and joint
          double diffangle = fmod(q_min(j) - q_curr(j), 2 * M_PI);
          // Subtract that angle from limit and go into the range by a
          // revolution
          double curr_angle = q_min(j) - diffangle + 2 * M_PI;
          if (curr_angle > q_max(j))
            q_curr(j) = q_min(j);
          else
            q_curr(j) = curr_angle;
        }
      }
    }

    for (unsigned int j = 0; j < q_max.data.size(); j++)
    {
      if (types[j] == KDL::BasicJointType::Continuous)
        continue;

      if (q_curr(j) > q_max(j))
      {
        if (!wrap || types[j] == KDL::BasicJointType::TransJoint)
          // KDL's default
          q_curr(j) = q_max(j);
        else
        {
          // Find actual wrapped angle between limit and joint
          double diffangle = fmod(q_curr(j) - q_max(j), 2 * M_PI);
          // Add that angle to limit and go into the range by a revolution
          double curr_angle = q_max(j) + diffangle - 2 * M_PI;
          if (curr_angle < q_min(j))
            q_curr(j) = q_max(j);
          else
            q_curr(j) = curr_angle;
        }
      }
    }

    Subtract(q_out, q_curr, q_out);

    if (q_out.data.isZero(boost::math::tools::epsilon<float>()))
    {
      if (rr)
      {
        for (unsigned int j = 0; j < q_out.data.size(); j++)
          if (types[j] == KDL::BasicJointType::Continuous)
            q_curr(j) = fRand(q_curr(j) - 2 * M_PI, q_curr(j) + 2 * M_PI);
          else
            q_curr(j) = fRand(q_min(j), q_max(j));
      }

      // Below would be an optimization to the normal KDL, where when it
      // gets stuck, it returns immediately.  Don't use to compare KDL with
      // random restarts or TRAC-IK to plain KDL.

      // else {
      //   q_out=q_curr;
      //   return -3;
      // }
    }

    q_out = q_curr;

    timediff = boost::posix_time::microsec_clock::local_time() - start_time;
    time_left = maxtime - timediff.total_nanoseconds() / 1000000000.0;
  }
  while (time_left > 0 && !aborted);

  return -3;
}

ChainIkSolverPos_TL::~ChainIkSolverPos_TL()
{
}


}