Design of sliding mode flight control system for a flexible aircraft

2021 ◽  
pp. 095441002110455
Author(s):  
Majeed Mohamed ◽  
Madhavan Gopakumar
Keyword(s):  
Control System ◽  
Rigid Body ◽  
Flight Control ◽  
High Speed ◽  
Sliding Mode ◽  
Flight Mechanics ◽  
Frequency Separation ◽  
Flight Control System ◽  
Flexible Aircraft ◽  
Aircraft Dynamics

The evolution of large transport aircraft is characterized by longer fuselages and larger wingspans, while efforts to decrease the structural weight reduce the structural stiffness. Both effects lead to more flexible aircraft structures with significant aeroelastic coupling between flight mechanics and structural dynamics, especially at high speed, high altitude cruise. The lesser frequency separation between rigid body and flexible modes of flexible aircraft results in a stronger interaction between the flight control system and its structural modes, with higher flexibility effects on aircraft dynamics. Therefore, the design of a flight control law based on the assumption that the aircraft dynamics are rigid is no longer valid for the flexible aircraft. This paper focuses on the design of a flight control system for flexible aircraft described in terms of a rigid body mode and four flexible body modes and whose parameters are assumed to be varying. In this paper, a conditional integral based sliding mode control (SMC) is used for robust tracking control of the pitch angle of the flexible aircraft. The performance of the proposed nonlinear flight control system has been shown through the numerical simulations of the flexible aircraft. Good transient and steady-state performance of a control system are also ensured without suffering from the drawback of control chattering in SMC.

Parameter Robust Flight Control System for a Flexible Aircraft

1994 ◽  
Vol 27 (13) ◽  
pp. 41-46
Author(s):  
F. Kubica ◽  
T. Livet ◽  
X. Le Tron ◽  
A. Bucharles
Keyword(s):  
Control System ◽  
Flight Control ◽  
Flight Control System ◽  
Flexible Aircraft ◽  
Robust Flight Control

scholarly journals Sliding Mode Implementation of an Attitude Command Flight Control System for a Helicopter in Hover

10.14311/748 ◽  
2005 ◽  
Vol 45 (4) ◽  
Author(s):  
D. J. McGeoch ◽  
E. W. McGookin ◽  
S. S. Houston
Keyword(s):  
Control System ◽  
Flight Control ◽  
Sliding Mode ◽  
Flight Control System ◽  
Design Standards ◽  
Handling Qualities ◽  
Control Scheme ◽  
Non Linear ◽  
Order Representation ◽  
Control Implementation

This paper presents an investigation into the design of a flight control system, using a decoupled non-linear sliding mode control structure, designed using a linearised, 9th order representation of the dynamics of a PUMA helicopter in hover. The controllers are then tested upon a higher order, non-linear helicopter model, called RASCAL. This design approach is used for attitude command flight control implementation and the control performance is assessed in the terms of handling qualities through the Aeronautical Design Standards for Rotorcraft (ADS-33). In this context a linearised approximation of the helicopter system is used to design an SMC control scheme. These controllers have been found to yield a system that satisfies the Level 1 handling qualities set out by ADS-33. 

Take-off and landing control for a coaxial ducted fan unmanned helicopter

2017 ◽  
Vol 89 (6) ◽  
pp. 764-776 ◽  
Author(s):  
Zhi Chen ◽  
Daobo Wang ◽  
Ziyang Zhen ◽  
Biao Wang ◽  
Jian Fu
Keyword(s):  
Control System ◽  
Flight Control ◽  
Control Strategy ◽  
Sliding Mode ◽  
Engineering Practice ◽  
Unmanned Helicopter ◽  
Flight Control System ◽  
Content Type ◽  
Ducted Fan ◽  
Coupling Characteristics

Purpose This paper aims to present a control strategy that eliminates the longitudinal and lateral drifting movements of the coaxial ducted fan unmanned helicopter (UH) during autonomous take-off and landing and reduce the coupling characteristics between channels of the coaxial UH for its special model structure. Design/methodology/approach Unidirectional auxiliary surfaces (UAS) for terminal sliding mode controller (TSMC) are designed for the flight control system of the coaxial UH, and a hierarchical flight control strategy is proposed to improve the decoupling ability of the coaxial UH. Findings It is demonstrated that the proposed height control strategy can solve the longitudinal and lateral movements during autonomous take-off and landing phase. The proposed hierarchical controller can decouple vertical and heading coupling problem which exists in coaxial UH. Furthermore, the confronted UAS-TSMC method can guarantee finite-time convergence and meet the quick flight trim requirements during take-off and landing. Research limitations/implications The designed flight control strategy has not implemented in real flight test yet, as all the tests are conducted in the numerical simulation and simulation with a hardware-in-the-loop (HIL) platform. Social implications The designed flight control strategy can solve the common problem of coupling characteristics between channels for coaxial UH, and it has important theoretical basis and reference value for engineering application; the control strategy can meet the demands of engineering practice. Originality/value In consideration of the TSMC approach, which can increase the convergence speed of the system state effectively, and the high level of response speed requirements to UH flight trim, the UAS-TSMC method is first applied to the coaxial ducted fan UH flight control. The proposed control strategy is implemented on the UH flight control system, and the HIL simulation clearly demonstrates that a much better performance could be achieved.

A Self-Repairing Control for the Uncertain System of a Helicopter Using Adaptive Sliding Mode Technology

2012 ◽  
Vol 468-471 ◽  
pp. 529-533 ◽  
Author(s):  
Fu Yang Chen ◽  
Wen Li Luan ◽  
Rui Hou
Keyword(s):  
Control System ◽  
Flight Control ◽  
Sliding Mode ◽  
Nonlinear Function ◽  
Uncertain System ◽  
Flight Control System ◽  
Adaptive Technology ◽  
Helicopter Flight ◽  
Control Scheme ◽  
Adaptive Control Scheme

In this paper, an adaptive control scheme is proposed for the uncertain flight control system of the helicopter with fault in vertical flight. The controller is designed using sliding mode theory and adaptive technology. In the controller, the nonlinear function is brought in, which can enlarge the small errors, and saturate the large errors. And it can make sure the good transient performances and stability of the helicopter flight control system. Finally, the simulation results of the nonlinear helicopter flight system illustrate the effectiveness and feasibility of the proposed scheme in the paper.

Control System Design of a Hex-Rotor Aircraft Based on the Neural Network Sliding Mode Method

2014 ◽  
Vol 971-973 ◽  
pp. 418-421 ◽  
Author(s):  
Chang Jun Zhao ◽  
Yue Bai ◽  
Xun Gong ◽  
Dong Fu Xu ◽  
Zhi Jun Xu
Keyword(s):  
Neural Network ◽  
Control System ◽  
Flight Control ◽  
Sliding Mode ◽  
Flight Performance ◽  
The Novel ◽  
Flight Control System ◽  
The Neural Network ◽  
Mode Method ◽  
Coupling Characteristics

For the existing Multi-rotor aircrafts, the under-actuation and strong coupling characteristics have a remarkable influence on their flight performance. In order to overcome this effect, a novel Hex-Rotor aircraft is proposed in this paper. Based on the unique configuration of its six driving rotors, the Hex-Rotor aircraft has the ability to achieve the real independent control on the space 6-DOF channels. An autonomous flight control system with neural network sliding mode is designed. The simulation proved that the novel Hex-Rotor aircraft has desired maneuvering capability,and thehe control system is able to guarantee the aircrafts tracking flight of the aircraft.

Sign in / Sign up

Export Citation Format

Share Document