Safe and Sustainable Unmanned Aircraft Trajectory Planning in Dense Urban Environments

Abstract

The paper discusses an unmanned aircraft (UA) trajectory planning tool for dense aerial operations in urban environments that considers not only the distance travelled, but also the Global Navigation Satellite Systems (GNSS) performance (e.g., accuracy and availability), separation to traffic and obstacles, energy expanded, time cost, impact of wind, impact of UA noise, and various other criteria. GNSS availability will drive the necessity to include alternative navigation sensors such as laser scanners, vision sensors and altimeters in the navigation mechanization to meet the required navigation performance necessary for urban operations. Furthermore, UAs operating in urban environments need to manage the prevailing urban wind effects like gusts and local vortices that constitute a high potential risk for failure and safety. Finally, this paper focusses on operations in the vicinity of transportation hubs (e.g., train stations, harbors, airports) where transfer of goods between UA and other modes of transportation is expected to result in an increased UA density, and thus the need for reliable separation methods of all participants. This paper will discuss the tool’s general structure and then provide some resulting using four of the above criteria to find the optimal trajectory, namely safe separation, time cost (distance and speed), energy expanded and the expected GNSS/alternative navigation performance along the trajectory. The energy used will consider the wind within the urban environment