On Dynamical Situations in Vehicle Routing Problems (DSVRP)

Abstract

This paper discusses the formulation of a stochastic Vehicle Routing Problem (VRP) process, introduced to existing deterministic VRP process, directing all efforts towards the dynamical situations that occur in a typical VRP setting as it applies to everyday real-life situations. It contrasts the dichotomy between static and dynamical situations in VRP, constructs and analyzes the relationship between static and dynamical situations in Vehicle Routing Problems, formulates an expression to describe the dynamical situation in VRP and relates the problem formulation to existing VRP with a view to solving the problem as it applies to real-life situations, a major trend in the business world today. With a view to achieving these, this paper associates the merits of reactivation of route, re-optimization of operation process and projects an anticipatory demand for a dynamical situation in VRP with stochastic requests via three stages: Pre-Decision States, Decisions States and Post-Decision States. First, as a reaction to anticipatory customers’ requests, the current routing plans need to be re-optimized and current customers’ request reactivated. Second, potential future requests need to be anticipated along current decision making since life itself is dynamic. Decisions need to be made in good time. Though, the limited time frame between when a vehicle leaves and returns to the depot often prohibits extensive optimization in both dimensions rather, answer the questions that arise on how to utilize the limited time effectively and judiciously, satisfying both the current and anticipatory customers equally.