Minimum-time trajectories for kinematic mobile robots and other planar rigid bodies with finite control sets

Abstract

This paper presents first attempts at a method for searching for time-optimal trajectories for a general model of mobile robots that includes Dubins and Reeds-Shepp cars, differential-drive robots, and omnidirectional robots as special cases. The paper takes as a starting point recent results by the authors that describe necessary conditions on the trajectories, based on Pontryagin's Maximum Principle. These necessary conditions reduce the problem of finding an optimal trajectory between start and goal to a few one-dimensional search problems. This search is not formally guaranteed to find a near-optimal trajectory if the sampling of the search space is not fine enough, but comparison to existing analytical results for specific systems, and a complete numerical search over trajectories with only a few control switches, demonstrates effectiveness of the method.