The objective of this project is to study and devise new means for motion planning for ground vehicles, using Raven as the prototype vehicle. More specifically, we try to determine smooth paths for Raven to follow, as it traverses waypoints; such paths have wide use in applications, for instance in following an astronaut as (s)he walks along a random path.
SPLINE BASED PATH PLANNING
We use a special kind of spline, called PH Spline, as the path for Raven to follow. The PH Spline performs a balancing act between two quantities that determine ideal paths: the path length and the path curvature. The way in which large ground vehicles follow such a trajectory has not been studied thoroughly before, which is precisely the objective of the current investigation. To determine the effectiveness of the trajectory, we compare the PH spline based trajectory with the default motion planning algorithms extant in ROS. We have made some encouraging progress thus far.
APPLICATION : GPS WAYPOINT FOLLOWING
We hare currently extending the above-mentioned PH Spline approach to make Raven follow an astronaut equipped with a GPS. In this experiment, both Raven and the astronaut have GPS devices that communicate with each other, and Raven attempts to follow him (her) in a smooth path. The figure below shows a typical graph resulting from this experiment.