为了解决四旋翼飞行器在外界扰动影响和系统模型参数存在不确定性情况下的精确轨迹跟踪控制问题,设计并验证了一种四旋翼飞行器的非线性轨迹跟踪控制器。首先建立了考虑执行机构特性的四旋翼飞行器数学模型,并将虚拟控制量映射到了实际中对电机的控制;然后通过在反步法轨迹跟踪控制中加入积分项,设计了一种基于积分型反步法的非线性轨迹跟踪控制器,消除模型参数不确定性及外界干扰引起的误差,仿真结果验证了该方法的可行性;最后,利用QBall2四旋翼飞行实验平台,对所设计的非线性轨迹跟踪控制器进行验证,实际飞行实验结果表明了所设计控制器的有效性,提高了实际飞行过程中外界干扰和不确定性下的四旋翼飞行器轨迹跟踪控制的精度。
In order to achieve precise trajectory tracking control for a quadrotor in the presence of external disturbances affecting and system model parameter uncertainty,a nonlinear trajectory tracking controller for the quadrotor is designed and verified. In this paper,the mathematical model of the quadrotor considering the actuator characteristics is firstly established and the virtual control is mapped to the motor control. Then,a nonlinear trajectory tracking controller based on integral backstepping method is designed by adding the integral term to the controller,to eliminate the errors caused by the uncertainty of model parameters and external disturbance. The numerical simulation results prove the feasibility of the method. Finally,the designed nonlinear trajectory tracking controller is applied to the QBall2 quadrotor flight test. The flight test results illustrate the effectiveness of the method,in which the tracking control accuracy is improved under the external disturbances and system model parameter uncertainty in the practical environment.