A Recycling Routing Problem of Broken Bikes With Incentives in Bike Sharing Systems

In recent years, the truck-based broken bike recycling mode (i.e., dedicated trucks deal with all transportation activities of broken bikes) in bike sharing systems (BSSs) has led to some problems in China, such as BSS operators have no willingness to collect broken bikes from a bike station in time. As a result, many BSSs are in bad condition due to an increase in the number of broken bikes. To solve this problem, many cities in China have started to introduce a new broken bike recycling mode, where some citizens (i.e., sanitation workers, freelancers, volunteers, etc.) are incentivized to participate in recycling activities. To deal with this new recycling mode, a recycling routing problem of broken bikes with incentives in BSSs is proposed, where the recycling operation is performed by citizen participants and a fleet of homogeneous trucks. Participants are incentivized to relocate broken bikes scattered in a BSS to transshipment stations in exchange for monetary rewards, and then these broken bikes are transported from transshipment stations to the depot by trucks. The problem is formulated as a mixed-integer linear programming model to minimize the total operation cost, and an efficient modified tabu search is developed to solve the proposed problem. Experimental results reveal the proposed broken bike recycling mode is beneficial for BSS operators to reduce the operation cost. Experimental results also show the proposed modified tabu search can generate high-quality solutions in short computing times.