基于模型拼接技术的四旋翼无人机全飞行包线建模

四旋翼无人机在军事和民用领域都有广泛的应用前景。然而,四旋翼无人机具有机载传感器准确性低与可靠性差、不同飞行条件下动力学模型差异大等特点。本文以四旋翼无人机为研究对象,系统地开展了飞行路径重构、频率域系统辨识、全飞行包线建模的相关研究工作。针对机载低成本传感器存在显著常值偏差与量测噪声统计学特性未知的缺点,采用基于EKF的飞行路径重构技术对在飞行试验中无人机的机体空速进行重构;针对不同飞行速度下四旋翼无人机动力学模型差异大的特点,采用频域法辨识得到不同飞行条件下的本体动力学模型;针对四旋翼无人机大跨域的高精度控制需求,利用模型拼接技术,系统性地提出了全飞行包线建模方案,经过验证,所提出模型拼接技术是准确可靠的。

Full flight envelope modeling of quadrotor vehicles based on model stitching technique

Quadrotor vehicles have found wide application in both military and civil fields. However, the onboard sensors of quadrotor vehicles are poor in reliability and accuracy, and the dynamic models of quadrotors vary considerably under different flight conditions. This study systematically examines the flight path reconstruction, frequency domain system identification, and full flight envelope modeling of quadrotor vehicles. To overcome the shortcomings of significant constant bias errors and unknown statistical characteristics of measurement noise of the airborne low-cost sensors, we use the flight path reconstruction technology based on Extended Kalman Filter(EKF) to reconstruct the airspeed of UAVs in flight tests. The frequency domain method is adopted to identify the body dynamics model under different flight conditions aiming at the different characteristics in dynamic models of quadrotor UAVs with different flight speeds. In view of the high-precision control requirements of the four rotor UAVs in large-span areas, a systematic full flight envelope modeling scheme based on the model stitching technology is proposed, which is verified to be accurate and reliable.