Akademik Veri Yönetim Sistemi
Journal of the Faculty of Engineering and Architecture of Gazi University, cilt.41, sa.1, ss.427-444, 2026 (SCI-Expanded, Scopus, TRDizin)
Bicycle-sharing systems (BPS) are widespread vehicle-sharing platforms where users can rent bicycles without the burden of purchasing and maintaining them. Rebalancing in BPS is critical because it ensures bicycle availability at high-demand points and ensures the sustainability of maintenance and distribution processes. In recent years, electric bicycles (e-bikes) have become popular in these systems due to their ease of use. Furthermore, the vehicles used for balancing in BPS can vary in terms of size, speed, and capacity. Therefore, this study addresses the static complete rebalancing problem (e-HSTYDP) with a heterogeneous fleet in BPS (e-BPS) using battery-swappable e-bikes. The e-HSTYDP is defined as selecting the vehicle type to be used in the redistribution of e-bikes among stations and performing the balancing process. A mixed-integer mathematical model is developed to consider separately the objectives of minimizing the total balancing time and the total cost. Since the e-HSTYDP is an NP-hard problem, a constructive heuristic based on the Clarke and Wright Savings (CWT) algorithm is developed to generate solutions for medium- and large-sized problems in reasonable time. The performance of the mathematical model and the s-CWT algorithm is investigated on 78 test problems ranging from 6 to 40 nodes. Experimental study shows that optimal or near-optimal solutions can be obtained in a short time (average 700 seconds) with the mathematical model for small-sized e-HSTYDP problems, while the solution time increases rapidly for medium- and large-sized problems. The s-CWT algorithm, on the other hand, is able to obtain feasible solutions for medium- and large-sized problems in less than 125 seconds and improves three solutions obtained with the model.