Macroscopic Fundamental Diagrams for Low-Altitude Air City Transport

Abstract

Low-altitude aircraft is being developed as a new mode of urban transport; consequently, the penetration of low-altitude passenger and delivery aircraft into the urban airspace is inevitable soon. This will give rise to new urban air transport systems, called low-altitude air city transport (LAAT) systems.

Inspired by urban road networks, this paper investigates the collective and aggregate aircraft traffic flow diagrams, i.e. Macroscopic Fundamental Diagrams (MFDs) for LAAT systems. Firstly, aircraft collision-avoidance models with cooperative distributed control algorithms from the literature are implemented to describe the low-altitude aircraft interactions, implying the microscopic traffic behavior. Afterwards, using the generalized definitions of Edie, the MFD is constructed for LAAT networks, by linking flow, density, and speed. Different case study examples are simulated to analyze the MFD shapes for LAAT systems, considering different microscopic collision avoidance approaches and the effects of aircraft and airspace settings.