Routing Optimization with Generalized Consistency Requirements

The consistent vehicle routing problem (ConVRP) aims to design synchronized routes on multiple days serve a group of customers while minimizing the total travel cost. It stipulates that should be visited at roughly same time (time consistency) by several familiar drivers (driver consistency). This paper generalizes ConVRP for any level driver consistency and additionally addresses route consistency, which means each can traverse most certain proportion different arcs planning days, guarantees familiarity. To solve this problem, we develop two set partitioning-based formulations, one based other schedules. We investigate valid lower bounds linear relaxations both formulations are used derive subset columns (routes schedules); within an optimal solution formulation. then reduced either achieve solution. Numerical results show our exact method effectively medium-sized instances in literature also some newly generated involving up 50 customers. Our solutions explore managerial findings with respect adoption measures practice. First, maintaining reasonably high levels requirements does not necessarily always lead substantial increase Second, potentially guaranteed adopting consistency. Third, may