Dynamic T‐search for accelerating searching speeds in Delaunay triangulation

Abstract

For realistic simulation of off‐road vehicles terrain surfaces have to be modeled in detail, and wheel‐surface contacting geometry must be well defined in order to obtain proper ground‐reaction and friction forces. Delaunay triangulation is one of the most widely used methods in modeling 3D terrain surfaces, and triangle‐search (T‐search) is a relevant algorithm for searching resultant triangular polygons. The T‐search method searches polygons in successive order and may not allow real‐time computation of off‐road vehicle dynamics if the terrain is modeled with many polygons, depending on the computer performance used in the simulation. Dynamic T‐search, which is proposed in this paper, combines conventional T‐search and the concept of a dynamic window, which is a moving subset of the database and where an actual search is made at each frame, by taking advantage of the information regarding dynamic characteristics of a simulated vehicle. Numerical tests show improvement of searching speeds by about 5 percent for randomly distributed triangles. For continuous searches along a vehicle path, which actually occur in a vehicle simulation, the searching speed of the new method becomes four times faster than the conventional one.