This paper investigates the adaptive incremental backstepping sliding mode control for the rotorcraft trajectory-tracking control problem to enhance the robustness to the matched uncertainty in the model. First, the incremental dynamics is used for the control design to exclude the adverse effect of the mismatched model uncertainties on the trajectory-tracking performance. Secondly, the sliding-mode control strategy is adopted in the second design stage of the backstepping controller, and the effect of switching gains on the controller robustness is thoroughly studied using the rotorcraft model with different levels of the matched uncertainties. To clarify the robustness enhancement using the adaptive selection of switching gains, this paper chooses three different control structures consisting of the traditional backstepping control and two backstepping sliding mode controls with the fixed or adaptively adjusted switching gains. These control designs are applied to the trajectory-tracking control for the helical-turn maneuver of the Bo-105 helicopter to compare their relative robustness to the matched uncertainties. The results prove that adaptive incremental backstepping sliding mode control shows much higher robustness than other two designs, and the controller even with the fixed switching gains can be used to improve the robustness of the pure backstepping control design. Therefore, the present adaptive incremental backstepping sliding mode control is effectively applicable with the rotorcraft model which typically contains many different sources of both matched and mismatched uncertainties.

中文翻译：

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基于增量反步滑模控制策略的旋翼机自适应轨迹跟踪控制

本文研究了旋翼飞行器轨迹跟踪控制问题的自适应增量反推滑模控制，以增强对模型中匹配不确定性的鲁棒性。首先，增量动力学用于控制设计，以排除不匹配的模型不确定性对轨迹跟踪性能的不利影响。其次，在反步控制器的第二设计阶段采用滑模控制策略，利用具有不同匹配不确定性水平的旋翼机模型，深入研究了开关增益对控制器鲁棒性的影响。为了阐明使用开关增益的自适应选择增强鲁棒性，本文选择了三种不同的控制结构，包括传统的反推控制和两种具有固定或自适应调整开关增益的反推滑模控制。这些控制设计应用于 Bo-105 直升机螺旋转弯机动的轨迹跟踪控制，以比较它们与匹配不确定性的相对鲁棒性。结果证明自适应增量反步滑模控制比其他两种设计表现出更高的鲁棒性，并且控制器即使具有固定的开关增益也可以用来提高纯反步控制设计的鲁棒性。所以，