This paper proposes a novel observer-based controller for Vertical Take-Off and Landing (VTOL) Unmanned Aerial Vehicle (UAV) designed to directly receive measurements from a Vision-Aided Inertial Navigation System (VA-INS) and produce the required thrust and rotational torque inputs. The VA-INS is composed of a vision unit (monocular or stereo camera) and a typical low-cost 6-axis Inertial Measurement Unit (IMU) equipped with an accelerometer and a gyroscope. A major benefit of this approach is its applicability for environments where the Global Positioning System (GPS) is inaccessible. The proposed VTOL-UAV observer utilizes IMU and feature measurements to accurately estimate attitude (orientation), gyroscope bias, position, and linear velocity. Ability to use VA-INS measurements directly makes the proposed observer design more computationally efficient as it obviates the need for attitude and position reconstruction. Once the motion components are estimated, the observer-based controller is used to control the VTOL-UAV attitude, angular velocity, position, and linear velocity guiding the vehicle along the desired trajectory in six degrees of freedom (6 DoF). The closed-loop estimation and the control errors of the observer-based controller are proven to be exponentially stable starting from almost any initial condition. To achieve global and unique VTOL-UAV representation in 6 DoF, the proposed approach is posed on the Lie Group and the design in unit-quaternion is presented. Although the proposed approach is described in a continuous form, the discrete version is provided and tested. Keywords: Vision-aided inertial navigation system, unmanned aerial vehicle, vertical take-off and landing, stochastic, noise, Robotics, control systems, air mobility, observer-based controller algorithm, landmark measurement, exponential stability.

翻译：本文提出了一种新型基于观测器的控制器，用于垂直起降（VTOL）无人机（UAV），该控制器可直接接收来自视觉辅助惯性导航系统（VA-INS）的测量值，并生成所需的推力和旋转转矩输入。VA-INS由视觉单元（单目或立体相机）和配备加速度计与陀螺仪的典型低成本六轴惯性测量单元（IMU）组成。该方法的主要优势在于适用于全球定位系统（GPS）不可用的环境。所提出的VTOL-UAV观测器利用IMU与特征测量值，精确估计姿态（方向）、陀螺仪偏差、位置及线速度。直接使用VA-INS测量值的能力使所提出的观测器设计在计算上更高效，因其消除了姿态与位置重建的需求。一旦运动分量被估计，基于观测器的控制器便用于控制VTOL-UAV的姿态、角速度、位置及线速度，引导飞行器沿六自由度（6 DoF）期望轨迹运动。闭环估计与基于观测器控制器的控制误差被证明在几乎任意初始条件下均呈指数稳定。为实现VTOL-UAV在6 DoF中的全局唯一表示，所提方法构建于李群之上，并给出了单位四元数表示。尽管所提方法以连续形式描述，本文同时提供并测试了其离散版本。关键词：视觉辅助惯性导航系统，无人机，垂直起降，随机噪声，机器人学，控制系统，空中机动性，基于观测器的控制器算法，地标测量，指数稳定性。