This paper presents a novel time-optimal motion planning strategy for
a mobile robot with kinematic constraints. The method works in environments
in presence of obstacles, without needing to generate the configuration space
for the robot. Further, it derives a minimum time first derivative smooth path,
as opposed to a minimum distance path which is commonly given by various present
solution techniques. The problem is solved in three stages: (i) A reduced
visibility graph for a point object is obtained. (ii) The reduced visibility
graph is converted into a feasible reduced visibility graph accounting for the
size and kinematic constraints of the robot. (iii) The A* algorithm is used to
search the feasible reduced visibility graph with the cost function being the
time of travel, to obtain a safe, time-optimal, smooth path. The algorithm runs
in polynomial time. The method has been tested in computer simulations and test
results are presented