Adaptive high‐order dynamic sliding mode control for a flexible air‐breathing hypersonic vehicle

Abstract

The problem of tracking control for a longitudinal air-breathing hypersonic vehicle model with flexible effects and intricate couplings between the engine dynamics and flight dynamics is investigated in this paper. In order to overcome the analytical intractability of this model, a simplified model is constructed during the feedback controller design. High-order dynamic sliding mode control is proposed to force the velocity and altitude of the flexible air-breathing hypersonic vehicle (FAHV) to the desired reference commands in finite time. In addition, the adaptive control method is employed to identify bounded uncertainties for eliminating the requirement of boundaries needed in the robust controller design and to guarantee the property of finite time stability without information of upper bound of uncertainties. Finally, simulations are presented to illustrate the effectiveness of the control strategies. ADAPTIVE HOSM CONTROL FOR A FLEXIBLE HYPERSONIC VEHICLE 1719As a result of slender geometries and light structures of this generic vehicle, significant flexible effects cannot be neglected in the controller design [7], because these modes may be harmful to system stability. In order to ensure safety and reliability, controller design for AHVs must guarantee stability of the flight system and provide a satisfying control performance [8]. Recently, an airbreathing hypersonic vehicle (FAHV) model with flexible dynamics was developed in [9,10]. On the basis of this kind of FAHV models, several studies on flight control design and simulation have been published in recent years. Because of the enormous complexity of the nonlinear dynamics, linearized model has been widely employed as the basis for flight control design. In [11], nonlinear longitudinal dynamics of a FAHV was directly linearized at a specified trim condition, and a linear quadratic regulator (LQR) was presented for a region in the neighborhood of the operating point. On the other hand, many efforts have been devoted to nonlinear control design for FAHVs. Sequential loop closure controller design [12][13][14] was based on the decomposition of FAHV equations into functional subsystems. The method followed combined robust adaptive dynamic inversion with back-stepping arguments to obtain control architecture. Approximate feedback linearization was applied in [15,16], to transform the FAHV model into a MIMO model, and an LQR strategy with integral augmentation based on dynamic inversion method was adopted to provide excellent tracking performance. In [17,18], a robust nonlinear tracking controller was constructed by using a minimax LQR control approach for the FAHV model developed by David and Serrani [19]. And the minimax optimal control design method was an extension of the LQR method to a class of uncertain systems. This controller design method provided robust stability and performance for the FAHV systems under varying flight conditions.In practice, the atmospheric properties and aerodynamic characteristics in the flight envelop of FAHVs are difficult...

Compromise Optimal Design using Control-based Analysis of Hypersonic Vehicles

“…For Equation (13), a right-half plane zero caused by the appearance of the negative lift exists as the elevator deflects trailing edge up. Without loss of generality, Z r3 is selected as this zero, given by [28], as follows:…”

“…Several advanced control approaches were adopted to design the robust adaptive controller for hypersonic vehicles. These techniques include high-order dynamic sliding mode control method [13], neural control mean [14], and adaptive back-stepping control strategies [15]. Establishing a model of the hypersonic vehicle is important for designing a feasible controller, thus ensuring the wavering stability and completing the command track.…”

Actuators Coupled Design Based Adaptive Backstepping Control of Air-breathing Hypersonic Vehicle**This work is supported by National Natural Science Foundation of China under Grants 61333008 and 61273153.

“…Another assignment is the introduction of a canard control surface. In Parker et al (2007), Rehman et al (2010), and Zong et al (2013), the item "elevator-to-lift" was exactly canceled by a canard control surface and the resulted plant was similar to the winged-cone configuration model. And consequently, various control techniques developed based on the winged-cone configuration model can be adopted in the controller design procedure.…”

Fuzzy disturbance observer‐based dynamic surface control for air‐breathing hypersonic vehicle with variable geometry inlets

“…Consider the AHV colsed-loop system that includes the AHV-VGI with the control inputs (39) and (54), the virtual controls (41), (44) and (49), the command filters (46) and (51), and the FDO system (38), (43), (48) and (53). Then, the AHV-VGI control system is uniformly stable.…”

“…These aerodynamic disturbances and the external disturbances may degrade the control performance, and even induce instability of the control system. Sliding mode control (SMC) has been widely studied for many years and extensively employed in industrial applications due to its conceptual simplicity, and in particular powerful ability to reject disturbances and plant uncertainties [37] [38]. Therefore, the SMC method is adopted to design the basic controller, and FDO is used to estimate the unknown factors including the uncertainties and disturbances.…”