This paper presents the modeling, simulation, and control of a small-scale electric powered quadrotor tail-sitter vertical take-off and landing unmanned aerial vehicle. In the modeling part, a full attitude wind tunnel test is performed on the full-scale unmanned aerial vehicle to capture its aerodynamics over the flight envelope. To accurately capture the degradation of motor thrust and torque at the presence of the forward speed, a wind tunnel test on the motor and propeller is also carried out. The extensive wind tunnel tests, when combined with the unmanned aerial vehicle kinematics model, dynamics model and other practical constraints such as motor saturation and delay, lead to a complete flight simulator that can accurately reveal the actual aircraft dynamics as verified by actual flight experiments. Based on the developed model, a unified attitude controller and a stable transition controller are designed and verified. Both simulation and experiments show that the developed attitude controller can stabilize the unmanned aerial vehicle attitude over the entire flight envelope and the transition controller can successfully transit the unmanned aerial vehicle from vertical flight to level flight with negligible altitude dropping, a common and fundamental challenge for tail-sitter vertical take-off and landing aircrafts. Finally, when supplied with the designed controller, the tail-sitter unmanned aerial vehicle can achieve a wide flight speed envelope ranging from stationary hovering to fast level flight. This feature dramatically distinguishes our aircraft from conventional fixed-wing airplanes.

中文翻译：

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宽飞行包线四旋翼尾座垂直起降无人机仿真与飞行试验

本文介绍了小型电动四旋翼尾座垂直起降无人机的建模、仿真和控制。在建模部分，对全尺寸无人机进行了全姿态风洞测试，以捕捉其在飞行包线上的空气动力学特性。为了准确捕捉存在前进速度时电机推力和扭矩的退化，还对电机和螺旋桨进行了风洞测试。广泛的风洞试验，结合无人机运动学模型、动力学模型和其他实际约束条件，如电机饱和和延迟，形成一个完整的飞行模拟器，可以准确地揭示实际飞行实验验证的实际飞机动力学。基于开发的模型，设计并验证了统一姿态控制器和稳定过渡控制器。仿真和实验都表明，所开发的姿态控制器可以在整个飞行包线内稳定无人机的姿态，并且过渡控制器可以成功地将无人机从垂直飞行过渡到水平飞行，高度下降可以忽略不计，这是一个常见的基本挑战。尾座垂直起降飞机。最后，当配备设计的控制器时，尾座无人机可以实现从静止悬停到快速平飞的宽飞行速度包络。这一特点使我们的飞机与传统的固定翼飞机显着区别。仿真和实验都表明，所开发的姿态控制器可以在整个飞行包线内稳定无人机的姿态，并且过渡控制器可以成功地将无人机从垂直飞行过渡到水平飞行，高度下降可以忽略不计，这是一个常见的基本挑战。尾座垂直起降飞机。最后，当配备设计的控制器时，尾座无人机可以实现从静止悬停到快速平飞的宽飞行速度包络。这一特点使我们的飞机与传统的固定翼飞机显着区别。仿真和实验都表明，所开发的姿态控制器可以在整个飞行包线内稳定无人机的姿态，并且过渡控制器可以成功地将无人机从垂直飞行过渡到水平飞行，高度下降可以忽略不计，这是一个常见的基本挑战。尾座垂直起降飞机。最后，当配备设计的控制器时，尾座无人机可以实现从静止悬停到快速平飞的宽飞行速度包络。这一特点使我们的飞机与传统的固定翼飞机显着区别。