# Reinventing Mobility Paradigms: Flying Car Scenarios and Challenges for Urban Mobility
## 1 Introduction  
Sustainable mobility is one of the main key challenges that stakeholders and policy makers have to face in order to give people the opportunity to move freely, communicate and establish relationships without harming themselves or the environment in which they live. Because of recent technological advancements, bringing urban mobility into the third dimension--the airspace--is now considered a real chance towards sustainable mobility (see for example the EU funded initiative for next generation urban mobility [1]). In this perspective, flying vehicles (such as Personal Aerial Vehicles, PAV, and Passengers Unmanned Aerial Vehicle, PUAV) and Urban Air Mobility (UAM) are receiving increasing attention for the interesting opportunity they offer to move people within urban areas. In fact, air connections provided by flying vehicles are expected to reduce surface transport congestion, integrate logistic chains and, at the same time, reduce infrastructure maintenance costs. Potential benefits in terms of improved transport reliability would affect not only emergency services and freight delivery, but also individual trips, while a reduction in travel times would lead to a reduction in trip delay and improved quality of life, which are some of the facets of sustainable mobility. From here on, \"flying cars\" are considered vehicles expected to move on both ground and air mode, so that transition between air and ground modes is possible. The potential benefits of using \"flyingcars\" in an urban context have caught the interest of scientists, engineers and companies, including, for instance, Uber [2] that is planning to start with aerial taxi services in the near future [3]. Following this trend and in the perspective of potentially feasible UAM scenarios, a growing number of flying vehicles are being developed or tested all over the world together with studies to understand which kind of features are more desirable for this type of vehicle [4; 5; 6]. At the same time, there is an increasing number of research programs dealing with the different aspects of this new form of urban mobility (see, for example, the _NASA Urban Air Mobility Grand Challenge Program_[7]; or the recent EC call _Towards sustainable air mobility_[8]). To simulate the effects of flying cars on urban mobility, the interactions occurring among flying and ground vehicles and with ground obstacles, as well as users' criteria leading to aerial mode choices, should be considered. Some studies have started simulating UAM scenarios by considering how to safely manage air vehicle separations in high-dense traffic conditions with several scheduling horizons [9; 10] and airspace integration concepts [11]. Free-flight conditions, where it is assumed that each vehicle is responsible for separations, have also been tested by using a computational guidance algorithm with collision avoidance capability [12]. Some other studies have used a MATSim [13] tool to simulate UAM transport performances with varying parameters (such as stations, access/egress, the number of vehicles, Vertical Take-off and Landing vehicle features) and by using the available Sioux Falls MATSim scenario [14; 15]. Finally, a comparative analysis for three case studies have investigated potential operational constraints for UAM services depending on specific mission types or environments [16]. Most of the previous studies make use of software agent technologies (from hereafter simply agents) [17; 18] as a tool to simulate UAM scenarios. Indeed, agents are autonomous, goal-oriented and time-persistent software entities that can be provided with different degrees of intelligence, learning, adaptive and pro-active capabilities [19], including social and self-organizing skills [20; 21].