Heuristic Methods for Capacitated Vehicle Routing Problem

The Capacitated Vehicle Routing Problem (CVRP) is a well known problem in the optimization literature. In this paper, we consider that there is a single depot (or distribution centre) that caters to the customer demands at a set of sales points (or demand centers) using vehicles with known limited capacities. The demand at each of these demand centers is assumed to be constant and known. Due to its limited capacity, the vehicles may need to make several trips from the depot for replenishment. The problem is to determine an optimal distribution plan that meets all the demands at minimum total cost. We propose a heuristic based on the well-known column generation approach to solve this problem. A sub-problem is then solved to generate additional columns for the master problem. This paper examines an approach for generating “good” columns (or distribution plans) together with heuristics for sequencing the customers within each distribution plan. The results are then compared to those obtained by using the genetic algorithm to demonstrate the performance of the methods.