Vehicle Assignment and Trip Chaining in Rural School Transportation with Explicit Repositioning Costs

This work addresses the problem of allocation and chaining of vehicles in rural school transport, considering multiple shifts, heterogeneous fleet and previously defined trips. An integer programming model is proposed that integrates vehicle selection, trip allocation, and temporal sequencing, incorporating repositioning costs between consecutive trips. The approach is applied to real instances of the Transcolar Rural System. To deal with complexity, filtering by capacity and gap control are used. The results show that good quality solutions can be obtained with a significant reduction in computational time, without relevant impact, in most instances, on the number of vehicles. High structural stability is observed, with variations concentrated in repositioning costs, indicating the model's suitability for large-scale applications.