numerical_differentiation_spline_smoother.h

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#ifndef NUMERICAL_DIFFERENTIATION_SPLINE_SMOOTHER_H_
#define NUMERICAL_DIFFERENTIATION_SPLINE_SMOOTHER_H_

#include <spline_smoother/spline_smoother.h>
#include <spline_smoother/spline_smoother_utils.h>

namespace spline_smoother
{

template <typename T>
class NumericalDifferentiationSplineSmoother: public SplineSmoother<T>
{
public:
  NumericalDifferentiationSplineSmoother();
  virtual ~NumericalDifferentiationSplineSmoother();

  virtual bool smooth(const T& trajectory_in, 
                      T& trajectory_out) const;
};

template <typename T>
NumericalDifferentiationSplineSmoother<T>::NumericalDifferentiationSplineSmoother()
{
}

template <typename T>
NumericalDifferentiationSplineSmoother<T>::~NumericalDifferentiationSplineSmoother()
{
}

template <typename T>
bool NumericalDifferentiationSplineSmoother<T>::smooth(const T& trajectory_in, 
                                                       T& trajectory_out) const
{
  bool success = true;
  int size = trajectory_in.trajectory.points.size();
  int num_traj = trajectory_in.trajectory.joint_names.size();
  trajectory_out = trajectory_in;

  if (!checkTrajectoryConsistency(trajectory_out))
    return false;

  // keep the first and last velocities intact

  // for every point in time:
  for (int i=1; i<size-1; ++i)
  {
    double dt1 = (trajectory_in.trajectory.points[i].time_from_start - trajectory_in.trajectory.points[i-1].time_from_start).toSec();
    double dt2 = (trajectory_in.trajectory.points[i+1].time_from_start - trajectory_in.trajectory.points[i].time_from_start).toSec();

    // for every (joint) trajectory
    for (int j=0; j<num_traj; ++j)
    {
      double dx1 = trajectory_in.trajectory.points[i].positions[j] - trajectory_in.trajectory.points[i-1].positions[j];
      double dx2 = trajectory_in.trajectory.points[i+1].positions[j] - trajectory_in.trajectory.points[i].positions[j];

      double v1 = dx1/dt1;
      double v2 = dx2/dt2;

      trajectory_out.trajectory.points[i].velocities[j] = 0.5*(v1 + v2);
    }
  }

  // all accelerations are 0 for now:
  for (int i=0; i<size; i++)
    for (int j=0; j<num_traj; j++)
      trajectory_out.trajectory.points[i].accelerations[j] = 0.0;

  return success;
}
}

#endif /* NUMERICAL_DIFFERENTIATION_SPLINE_SMOOTHER_H_ */

---

spline_smoother
Author(s): Mrinal Kalakrishnan / mail@mrinal.net
autogenerated on Fri Jan 11 09:15:07 2013