fritsch_butland_spline_smoother.h
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00034 
00037 #ifndef FRITSCH_BUTLAND_SPLINE_SMOOTHER_H_
00038 #define FRITSCH_BUTLAND_SPLINE_SMOOTHER_H_
00039 
00040 #include <spline_smoother/spline_smoother.h>
00041 
00042 namespace spline_smoother
00043 {
00044 
00053 template <typename T>
00054 class FritschButlandSplineSmoother: public SplineSmoother<T>
00055 {
00056 public:
00057   FritschButlandSplineSmoother();
00058   virtual ~FritschButlandSplineSmoother();
00059 
00060   virtual bool smooth(const T& trajectory_in, 
00061                       T& trajectory_out) const;
00062 };
00063 
00064 template <typename T>
00065 FritschButlandSplineSmoother<T>::FritschButlandSplineSmoother()
00066 {
00067 }
00068 
00069 template <typename T>
00070 FritschButlandSplineSmoother<T>::~FritschButlandSplineSmoother()
00071 {
00072 }
00073 
00074 template <typename T>
00075 bool FritschButlandSplineSmoother<T>::smooth(const T& trajectory_in, 
00076                                           T& trajectory_out) const
00077 {
00078   bool success = true;
00079 
00080   int size = trajectory_in.request.trajectory.points.size();
00081   int num_traj = trajectory_in.request.trajectory.joint_names.size();
00082   trajectory_out = trajectory_in;
00083 
00084   if (!checkTrajectoryConsistency(trajectory_out))
00085     return false;
00086 
00087   // keep the first and last velocities intact
00088 
00089   // for every point in time:
00090   for (int i=1; i<size-1; ++i)
00091   {
00092     double h1 = (trajectory_in.request.trajectory.points[i].time_from_start - trajectory_in.request.trajectory.points[i-1].time_from_start).toSec();
00093     double h2 = (trajectory_in.request.trajectory.points[i+1].time_from_start - trajectory_in.request.trajectory.points[i].time_from_start).toSec();
00094 
00095     // for every (joint) trajectory
00096     for (int j=0; j<num_traj; ++j)
00097     {
00098       double s1 = (trajectory_in.request.trajectory.points[i].positions[j] - trajectory_in.request.trajectory.points[i-1].positions[j])/h1;
00099       double s2 = (trajectory_in.request.trajectory.points[i+1].positions[j] - trajectory_in.request.trajectory.points[i].positions[j])/h2;
00100 
00101       double alpha = (1 + h2/(h1+h2))/3.0;
00102 
00103       double vel = 0.0;
00104       if (s1*s2 > 0)
00105       {
00106         vel = (s1*s2)/(alpha*s2 + (1.0-alpha)*s1);
00107       }
00108       trajectory_out.request.trajectory.points[i].velocities[j] = vel;
00109       trajectory_out.request.trajectory.points[i].accelerations[j] = 0.0;
00110     }
00111   }
00112   return success;
00113 }
00114 }
00115 
00116 #endif /* FRITSCH_BUTLAND_SPLINE_SMOOTHER_H_ */


spline_smoother
Author(s): Mrinal Kalakrishnan / mail@mrinal.net
autogenerated on Thu Dec 12 2013 11:09:50