[ompl-users] Distance metric and interpolation for RRTs

[Anand <ana...@gm...>]

In OMPL, the distance metric used (distance()) and the way in which states
are connected (interpolate()) are encapsulated as part of the state space.

For example, the DubinsStateSpace uses the path length of the Dubins curve
to compute the distance() and interpolate().

Does it make sense for an RRT to use a different distance metric for
nearest neighbor computations, than what is used for interpolation?

In my scenario (planning for a car-like robot), I wonder if it makes sense
to speed up nearest neighbor searches by using a distance metric other than
Dubins (say Euclidean distance) to find nearest neighbors, but still use
Dubins to connect states? This will allow me to use nearest neighbor data
structures like GNAT, which I can't otherwise do if I use the Dubins
distance metric.

If not, are there any alternative data structures I can use to speed up
nearest neighbor searches for a Dubins-like non-metric space?

Thanks,
Anand