Driver's workload analysis for waste collection vehicle routing problem

This paper analyses the workload of the drivers for a waste collection benchmark problem. The problem involves ten data sets with different number of customers to be served and different number of disposal facilities available. A heuristic algorithm, namely Different Initial Customer from a previous study is used to solve the problem by constructing vehicles routes for the drivers with two main objectives; to minimize the total distance travelled and to minimize the total number of vehicles needed to collect the waste. The results compared well with other solutions in the literature. However, the solutions did not consider the balance of the vehicle routes constructed. Thus in this paper, we evaluate the quality of the solutions in terms of the total distance travelled assigned to each driver. First, we identify the distance travelled of each driver using Different Initial Customer procedure for the data sets. Then, we calculate standard deviation (SD) of each solution in order to analyze the drivers' workload. Low SD value indicates small workload difference between drivers. Finally, the SD value is compared and the analysis shows that the solution with the minimum SD may increase the total distance travelled as well as the number of drivers needed to complete the collection.