PT Journal
AU Wittwer, D
   Schmidt, T
TI Utilization-oriented Harvest Logistics: Vehicle Routing and Scheduling of Forage Harvesters, Transfer and Transport Vehicles with Synchronization Constraints
SO Logistics Journal : Proceedings
PY 2021
VL 2021
IS 17
DI 10.2195/lj_Proc_wittwer_en_202112_01
DE Erntelogistik; Gemischtganzzahlige Programmierung; Synchronisierung; Vehicle Routing Problem; harvest logistics; mixed-integer programming; synchronization
AB Agricultural contractors are logistics service providers for various field operations in agriculture. Restrictions imposed by nature, lack of personnel, high-priced agricultural machinery and small margins require contractors to make efficient use of their fleet of agricultural machinery. In order to achieve a short completion time, as is particularly necessary for harvesting, the dispatcher aims to minimize travel times between the operating locations and to increase the utilization of harvesting machines, e.g. forage harvesters and combine harvesters. This paper examines the harvesting process involving forage harvesters and support vehicles (transfer vehicles and transport vehicles). Here, if insufficient support vehicles are available, the forage harvester needs to pause operation on the field while waiting for a support vehicle that can receive the harvested biomass. Typically, teams of harvesters and support vehicles are assembled prior to the start of the harvesting process and remain in this constellation until all fields in the planning period have been harvested. In this study, we investigate the time savings when vehicles are not tied to their team and can thereby harvest each field in a new constellation of vehicles. This paper presents two mathematical models describing the harvesting process with forage harvesters, transfer vehicles and transporters with a focus on the utilization of the forage harvesters with fixed and variable team compositions, respectively. These models are solved via mixed-integer programming with the Gurobi solver.
ER