Shortest path computations under trajectory constraints for ground vehicles within agricultural fields

This paper addresses the task of finding the shortest path to a target point on the boundary of an agricultural working area given a current position and heading of a ground vehicle within that area. Constraints such as admittance of turning on the spot, lane- and corridor-constraining motion as well as repressed area minimization are taken into account. We distinguish between orchard- and vineyard-like areas and agricultural fields growing, in particular, rapeseed and cereals. For the former application, dynamic programming and label-correcting algorithms are compared and, based on a coordinate transformation, a heuristic is motivated therefore. For the latter agricultural field application, we constrain the shortest path objective by allowing agricultural machinery to only use already existing tractor-lane traces and thus introduce a repressed area minimization constraint. Therefore, a customized and novel shortest path finding method is derived, before its optimality is proven. The outcome of this work is equally applicable for autonomous as well as manually driven agricultural ground vehicles.