Free-floating Bike-sharing System Research Articles

A static free-floating bike repositioning problem with multiple heterogeneous vehicles, multiple depots, and multiple visits

In this paper, a bike repositioning problem with multiple depots, multiple visits, and multiple heterogeneous vehicles for the free-floating bike-sharing system (FFBSS) is studied. Two types of nodes (i.e., easily and hardly access nodes) with different penalties are defined to represent different convenience levels of getting bikes from the FFBSS. The objective of the repositioning is to minimize the weighted sum of the inconvenience level of getting bikes from the system and the total unmet demand and the total operational time. To solve this problem, an enhanced version of chemical reaction optimization (CRO) is developed. A loading and unloading quantity adjustment procedure with the consideration of the node characteristics, including the type of node and its current state (i.e., in a balanced, surplus, or deficit state) is proposed and incorporated into this version to improve its solution quality. A concept of the nearby-node set is also proposed to narrow the search space. Numerical results are presented and indicate that compared to the traditional CRO and CPLEX, the enhanced CRO improves solution quality and has potential to tackle the repositioning problem for larger, longer repositioning duration, and more vehicle instances. The results also demonstrate the effectiveness of the proposed adjustment procedure.

Cyclist Satisfaction Evaluation Model for Free-Floating Bike-Sharing System: A Case Study of Shanghai

The free-floating bike-sharing system (FFBS) is an innovative public bicycle service, which is widely popular throughout China. In comparison to traditional station-based system, FFBS allows cyclists to park the bicycles in any non-motorized parking area so that the convenience can be improved greatly. Moreover, smart devices inside the free-floating bicycle can provide real-time tracking information which offers convenience for intelligent management. This study adopts the structural equation model to measure what factors influence people’s willingness to use the system and how the indicators inside the system interact with each other. Unlike the long-standing use of maximum likelihood estimation method, an approach of partial least squares estimation is used in this paper to remove the restriction of multivariate normal distribution. Based on the questionnaire carried out in 32 locations in Shanghai, a conceptual framework cyclist satisfaction index model is established, which includes three levels with 50 indicators. Then, to analyze the different perception among different kinds of cyclists, the study divides them into two groups: commuters and non-commuters. The parameter calibration for commuters and non-commuters are calculated separately. Finally, by virtue of importance-performance analysis (IPA) matrices, the problems in the existing service system are identified. The results demonstrate five aspects including riding environment, riding safety, government intervention, laws and staff service need urgent improvement. According to these findings, innovative countermeasures such as monitoring platform and electronic fences are under construction to prompt the use of FFBS.

A modeling framework for the dynamic management of free-floating bike-sharing systems

Given the growing importance of bike-sharing systems nowadays, in this paper we suggest an alternative approach to mitigate the most crucial problem related to them: the imbalance of bicycles between zones owing to one-way trips. In particular, we focus on the emerging free-floating systems, where bikes can be delivered or picked-up almost everywhere in the network and not just at dedicated docking stations. We propose a new comprehensive dynamic bike redistribution methodology that starts from the prediction of the number and position of bikes over a system operating area and ends with a relocation Decision Support System. The relocation process is activated at constant gap times in order to carry out dynamic bike redistribution, mainly aimed at achieving a high degree of user satisfaction and keeping the vehicle repositioning costs as low as possible. An application to a test case study, together with a detailed sensitivity analysis, shows the effectiveness of the suggested novel methodology for the real-time management of the free-floating bike-sharing systems.

Planning and Design of Equitable Free-Floating Bike-Sharing Systems Implementing a Road Pricing Strategy

Promoting a more sustainable development of urban realities is one of the most important goals of the recent decades. One possible strategy to undertake in order to achieve this objective is the implementation of a road pricing: tolling private cars when passing by certain roads of the network could be a way to tone down the traffic congestion and, at the same time, encourage the shifting towards more sustainable means of transport. In this context, we suggest a method to distribute in a fair way the outcomes/revenues of this pricing strategy. In particular, we propose to design a free-floating bike-sharing system whose resources could be allocated in the territory according to spatial and social equity principles. The relation between the amount of the tolls, the number of days of application of the policy, and the pursued equity is investigated, and both a numerical application (to a test network and to a real case study) and a sensitivity analysis in support of the method are enclosed.

A Relocation Strategy for Munich's Bike Sharing System: Combining an operator-based and a user-based Scheme

Abstract: Based on a detailed GPS-Data Analysis for a free-floating Bike Sharing System, mobility patterns of the bike usage were identified spatially and temporally. Depending on different factors like seasons, weather conditions, time of the day and holidays/weekends, we built up a demand model in order to forecast the upcoming demand at certain time and place. This model reveals optimal fleet distributions for different zones in the operating area and for different time slots. To redistribute the fleet a reasonable relocation strategy was created in order to obtain an optimal distribution of bikes within the operating area. Two different kinds of relocation methods are evaluated: an operator-based relocation strategy, where at least one vehicle redistributes a part of the fleet. Additionally, a user-based relocation scheme was created: based on pricing benefits for the user, at least a share of the needed relocations are conducted by users, almost cost-neutral. There is a certain threshold though, when the necessary fleet relocations are too urgent and an operator-based intervention is inevitable. At the end, we carried out a validation to show what kind of effects a real life relocation could imply.