Simulation and Validation of an Air Data Sensing System for Small Fixed-Wing UAVs

This paper presents a novel approach to measuring airspeed, angle of attack, and sideslip angle for small fixed-wing Unmanned Aerial Vehicles (UAVs) using a simplified Flight Air Data System (FADS). Unlike conventional systems, which rely on multiple sensors and complex models, this study utilizes a pitot-static tube and a strategically designed nosecone with four static pressure ports. The primary objective is to optimize air data measurement accuracy while minimizing system complexity and sensor count. The methodology includes computational simulations to validate the pressure differential data for varying flight conditions, including velocity ranges (0–30 m/s), angles of attack (-30° to 30°), and sideslip angles (-30° to 30°). Differential pressure data were processed using fundamental aerodynamic principles to calculate airspeed and drift angles. Simulation results demonstrate that the proposed system accurately captures the trends in all three measurements. The average error observed in velocity measurement was 1.587 m/s, while angle of attack and sideslip angle measurements exhibited average errors of 2.678° and 2.670°, respectively. The system shows higher accuracy within specific angular ranges, such as -20° to -14° for angle of attack. This research introduces an efficient and cost-effective air data sensing method, making it suitable for small UAV applications. Future work includes wind tunnel experiments with 3D-printed prototypes to further validate the system's performance under real-world conditions.