Route Planning For Capacitated Agricultural Machines Based On Ant Colony Algorithms

In agricultural capacitated field operations, i.e. operations where material is transported into the field (e.g. seeding, spraying and fertilizing) or out of the field (harvest), a number of routes are needed for a primary unit to cover the entire field due to its capacity constraint. Hence, the operation of a primary unit must be carefully planned to improve the field operation efficiency. In this paper, an approach for the generation of optimal optimized route to be followed by primary units aimed at reducing the travelled nonworking distance is presented. The presented approach consists of two stages. The first stage is about the field geometrical representation where the field is split into parts; the headland area in which the machines can make turns, and field body that is the main cropping area. In geometrical sense, both of them are expressed as a geometrical map using geometrical primitives, such as point, line segment, and polygon. The field body is covered by a set of parallel straight field-work tracks that has two intersections with the field boundary. The second stage is to find the optimal route which is formulated as a capacitated vehicle routing problem (CVRP). It was solved by implementing the ant colony algorithm combined with the Clarke-Wright savings algorithm. A case study is presented based on two fields; the results show that, by using the optimum routing generated, the non-working distance can be reduced in the range of 47.02% 49.76 %compared with the conventional work pattern.