Purpose

The aim of this paper is to design a nonlinear disturbance observer-based control (DOBC) method obtained by patching a control method developed using a robust adaptive technique and a DO.

Design/methodology/approach

For designing a DOBC, initially a class of nonlinear system is considered with an external disturbance. First, a DO is designed to estimate the external disturbances. This estimate is combined with the controller to reject the disturbances and obtain the desired control objective. For designing a controller, the robust sliding mode control theory is used. Furthermore, instead of using a constant switching gain, an adaptive gain tuning criterion is designed using Lyapunov candidate function. To investigate the stability and effectiveness of the developed DOBC, stability analysis and simulation study are presented.

Findings

The major findings of this paper include the criteria of designing the robust adaptive control parameters and investigating the disturbance rejection when robust adaptive control based DOBC is developed.

Practical implications

In practice, the flight of quadrotor is affected by different kind of external disturbances, thus leading to the change in dynamics. Hence, it is necessary to design DOBCs based on robust adaptive controllers such that the quadrotor model adapts to the change in dynamics, as well as nullify the effect of disturbances.

Originality/value

Designing DOBCs based on robust control method is a common practice; however, the robust adaptive control method is rarely developed. This paper contributes in the domain of DOBC based on robust adaptive control methods such that the behavior of controller varies with the change in dynamics occurring due to external disturbances.

中文翻译：

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第 1 部分：四旋翼具有扰动观测器的鲁棒自适应控制

目的

本文的目的是设计一种基于非线性干扰观测器的控制 (DOBC) 方法，该方法通过修补使用鲁棒自适应技术和 DO 开发的控制方法获得。

设计/方法/方法

为了设计 DOBC，首先考虑一类具有外部干扰的非线性系统。首先，DO 旨在估计外部干扰。该估计与控制器相结合以拒绝干扰并获得所需的控制目标。为了设计控制器，使用鲁棒滑模控制理论。此外，不是使用恒定的开关增益，而是使用李雅普诺夫候选函数设计自适应增益调谐标准。为了研究开发的 DOBC 的稳定性和有效性，提出了稳定性分析和模拟研究。

发现

本文的主要发现包括设计鲁棒自适应控制参数和研究基于 DOBC 鲁棒自适应控制时的干扰抑制标准。

实际影响

在实践中，四旋翼飞行器的飞行受到各种外部干扰的影响，从而导致动力学的变化。因此，有必要设计基于鲁棒自适应控制器的 DOBC，使四旋翼模型适应动力学的变化，并消除干扰的影响。

原创性/价值

基于鲁棒控制方法设计 DOBC 是一种常见的做法；然而，鲁棒自适应控制方法很少被开发出来。本文在基于鲁棒自适应控制方法的 DOBC 领域做出了贡献，使得控制器的行为随着由于外部干扰而发生的动态变化而变化。