| Summary |
This paper proposes a new static bike repositioning problem that maintenance operation is simultaneously considered. In this problem, a broken bike at a station can be either collected on the relocation vehicle to be sent back to the depot or repaired on-site to restore its function during repositioning. Thison-site repair becomes a new strategy that is examined in this paper and new to
the literature. The problem is formulated as a mixed-integer linear programming problem that determines the number of deployed vehicles, the loading and unloading quantities for normal bikes at all stations, and the number of collected and repaired broken bikes at all stations such that the weighted sum of the total service time and the penalties associated with the deviations from the
targeted inventory level is minimized. Using the real-world case of Youbike in Taiwan, this paper demonstrates the on-site repair strategy can reduce the repositioning cost and deviations from the target inventory levels more than mere collection strategy. Sensitivity analyses show that the shorter repairing time, larger vehicle, and higher penalty for deviations from the target inventory level can obtain strategies with smaller deviation and shorter travel time.
Moreover, a revised problem which includes service time constraint is proposed and the numerical studies show that the increase in allowable service time can reduce the number of deployed vehicles and the total service time.
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