An event-based simulation for optimizing one-way car-sharing systems

Car-sharing systems allow registered users to use cars spread throughout an urban area: vehicles are at their disposal anytime they need one against some amount of money per minute rental. The customer avoids some issues linked to the ownership of a car such as insurance fees, maintenance or parking. Such a system is beneficial for the society in terms of environmental, energetic impacts and congestion. It completes the urban transportation service by allying the efficiency of public transportation and the flexibility of owning a vehicle. Car-sharing systems can be classified in different families depending on the rental conditions. For instance, free-floating systems allow people to park the vehicles anywhere in city area whereas non-free floating impose to users to park them inside stations with limited number of allowed spots. In this last family, another differentiating feature is the "one-way/two-way" characteristic: two-way systems force the user to return the car to the location where it was picked-up whereas one-way systems allow drop-off at any station. We focus in this research mainly on non-free-floating one-way electric systems. The system operations naturally induce imbalances in the distribution of vehicles that need to be corrected by performing relocations. Our aim is to model and simulate those operations to first analyze the way the system evolves with time and then to test different management policies for operations and especially relocations in order to both maximize customers' satisfaction and make the operation of the system sustainable for the operator