Joint vehicle assembly-routing problems: An integrated modeling and optimization approach

This article examines logistical systems where it is desirable to appropriately ascertain the joint composition of the sequences of vehicles that are to be physically connected along with determining their delivery routes. Such assembly-routing problems occur in the truck manufacturing industry, for example, where combinations of trucks to be delivered to dealerships are composed and are subsequently dispatched via appropriately optimized delivery routes, which are in turn restricted by the particular sequence in which the trucks are connected. A similar structure is exhibited in the business of shipping goods via boat-towed barges along inland waterways, or via trains through railroad networks. We present a novel unifying model and a column generation-based optimization approach for this challenging class of joint vehicle assembly-routing problems. In addition, we suggest several extensions to accommodate particular industrial settings where assembly sequence-dependent delivery routes are necessary, as well as those where driver- and equipment-based restrictions are imposed. Computational experience is provided using realistic data from a case-study involving a major truck manufacturing company to demonstrate the applicability of the proposed methodology in practice. © 2008 Wiley Periodicals, Inc. NETWORKS, 2009