This paper proposes an appointed-time prescribed performance adaptive attitude controller with an event-triggered (ET) mechanism and optimized quantized communication for quadrotor unmanned aerial vehicles (QUAVs) in an uncertain environment. An appointed-time prescribed performance function is first designed to improve the convergence performance of attitude tracking errors considering different convergence time requirements and the convergence rate. In addition, to reduce the communication burden, a switching threshold ET mechanism and an optimized hybrid quantizer are adopted by using the K-means method. The ET mechanism not only involves the fixed threshold but also refers to the change rate of calculated control law flexibly and predictively. The optimized hybrid quantizer creatively classifies signals by their value and maximizes the advantage of each quantization method to reduce excessive quantization errors. It is shown that the proposed control scheme ensures that the closed-loop signals are uniformly ultimately bounded according to the Lyapunov method. Finally, the simulation experiments are implemented on a QUAV to demonstrate the effectiveness of the presented control scheme.

本文提出了一种针对不确定环境下四旋翼无人机（QUAV）的具有事件触发（ET）机制和优化量化通信的指定时间规定性能自适应姿态控制器。考虑到不同的收敛时间要求和收敛速度，首先设计了指定时间的规定性能函数，以提高姿态跟踪误差的收敛性能。此外，为了减轻通信负担，利用K均值方法采用切换阈值ET机制和优化混合量化器。 ET机制不仅涉及固定阈值，还涉及灵活、可预测地计算控制律的变化率。优化的混合量化器创造性地根据信号的值对信号进行分类，并最大限度地发挥每种量化方法的优势，以减少过多的量化误差。结果表明，所提出的控制方案确保闭环信号根据李雅普诺夫方法最终一致有界。最后，在QUAV上进行仿真实验，验证所提出控制方案的有效性。