This filter removes the smallest segments from a trajectory until at most
MAX_NUM_POINTS (currently 16) are left. The reason for doing this is that
the Katana arm only supports trajectories with at most MAX_NUM_POINTS.
All desired velocities and accelerations are removed from the trajectory.
This works if this filter is used in conjunction with the
JointTrajectoryActionController from the katana
package, because it recomputes splines for velocities and accelerations
anyway. It would not work with PR2's JointTrajectoryActionController,
which only computes linear segments if the velocities are missing.
Also, this filter does not check if the resulting trajectory is collision-free,
although it should.
katana_trajectory_filter is ...
