小型变体无人机动力学建模及配平分析

Dynamics Modeling and Trimming Analysis for Small Morphing UAV

为了更好地分析变体无人机(Unmanned Aerial Vehicle,UAV)在变体过程中的动态响应,针对一种小型变后掠翼无人机,通过静矩来描述变体过程中重心位置的变化,推导了其六自由度非线性运动方程。变体飞机相对于固定翼飞机的运动学方程多出变体过程中引起的惯性力和惯性力矩项以及转动惯量和惯性积的微分项。利用准定常假设来简化计算变体过程中的气动力,认为在变体的任一瞬时,全机的气动力取决于该瞬时飞机的静态构型和飞行状态。从计算结果可知,在一定飞行速度和飞行高度范围内,影响气动参数的主要变量为机翼后掠角和迎角。为了确保变体飞机在变体过程中具有较理想的静稳定度,通过配平给出了不同构型时飞机重心在机体纵轴上的合理位置,有助于变体飞机控制系统设计。

In order to better analyze the dynamic response of morphing Unmanned Aerial Vehicle（ UAV）,the moving of the center of gravity is described by quiet moment,and the six free nonlinear equations of motion for a small variable sweep UAV is derived.The kinematic equation of morphing aircraft has more items that are inertial force and inertial moment than fixed wing plane. The aerodynamic forces and moments in the process of morphing are calculated with the quasi-steady assumption,the aerodynamic force is depended on the static configuration and flight state of morphing aircraft at the moment of morphing.From the results it can be known that the main variable that affects the aerodynamic parameters ie sweep angle and angle of attack within a certain range of flight speed and altitude.To make sure that the morphing aircraft has an ideal static stability margin,the responsible position of the center of gravity on the longitudinal axis of the body at different configurations is obtained by trimming,which lays a foundation for the control system design for the morphing aircraft.