Flight characteristics of a fixed wing unmanned aircraft systems for aerial surveillance of agricultural systems

Abstract

Abstract. This paper presents measures of performance for a fixed wing unmanned aircraft system (UAS) serving as a sensor platform for production agriculture mission profiles. UAS deployment in production agriculture require that onboard navigation systems guide the aircraft according to predefined flight plans for accurate sensor placement. The objective of this research was to evaluate fixed wing UAS performance measures for predefined flight paths, indicated air speed (IAS), and altitude (MSL). A transit pattern was selected to test the autonomous navigation system, featuring GPS waypoints and rectangular loops, with each complete loop shifting incrementally across a research field. Fourteen flights covering areas of 16.2, 32.4, or 64.7 ha were conducted over a two-month period with variable environmental conditions. Two 16.2 ha and two 32.4 ha flights were selected for analysis. Root mean squared error (RMSE) results for the flight path data were between 3.88 m and 14.05 m, with a maximum difference of 52.8 m. IAS analysis found that the average was slightly higher than expected, with an RMSE between 0.8 m s-1 and 1.74 m s-1. The altitude hold capability (MSL) was close to its predefined value; however, an RMSE range between 2.04 m and 3.02 m suggested deviations from the target MSL for different flights. A tolerance limit analysis confirmed these findings. Results suggested that measures of different flight characteristics can be used to define UAS performance as a sensor platform. Research results demonstrated both great promise, and an associated potential for improvement, in currently available unmanned aircraft with autonomous navigation systems deployed for sensor placement over large parcels of agricultural land.