Effects of the actively morphing root chord and taper on helicopter energy

2019 ◽  
Vol 92 (2) ◽  
pp. 264-270
Author(s):  
Firat Sal
Keyword(s):  
Control System ◽  
Energy Consumption ◽  
Flight Control ◽  
Design Methodology ◽  
Chord Length ◽  
Flight Control System ◽  
Content Type ◽  
Helicopter Blade ◽  
Blade Root ◽  
Practical Implications

Purpose The purpose of this paper presents the effects of actively morphing root chord and taper on the energy of the flight control system (i.e. FCS). Design/methodology/approach Via regarding previously mentioned purposes, sophisticated and realistic helicopter models are benefitted to examine the energy of the FCS. Findings Helicopters having actively morphing blade root chord length and blade taper consume less control energy than the ones having one of or any of passively morphing blade root chord length and blade taper. Practical implications Actively morphing blade root chord length and blade taper can be used for cheaper helicopter operations. Originality/value The main originality of this paper is applying active morphing strategy on helicopter blade root chord and blade taper. In this paper, it is also found that using active morphing strategy on helicopter blade root chord and blade taper reasons less energy consumption than using either passively morphing blade root chord length plus blade taper or not any. This causes also less fuel consumption and green environment.

Analysis of combined passively and actively morphing blade root chord length and blade taper for helicopter control

2019 ◽  
Vol 92 (2) ◽  
pp. 172-179
Author(s):  
Firat Sal
Keyword(s):  
Flight Control ◽  
Chord Length ◽  
Flight Control System ◽  
Control Effort ◽  
Simultaneous Application ◽  
Content Type ◽  
Helicopter Control ◽  
Helicopter Blade ◽  
Blade Root ◽  
Autonomous Helicopter

Purpose The purpose of this study is to examine the effect of passive and active morphing of blade root chord length and blade taper on the control effort of the flight control system (FCS) of a helicopter. Design/methodology/approach Physics-based helicopter models, which are functions of passive and active morphing, are created and applied in helicopter FCS design to determine the control effort. Findings Helicopters, having both passively and actively morphing blade root chord length and blade taper, experience less control effort than the ones having either only passively morphing blade root chord length or only blade taper or only actively morphing blade root chord length and blade taper. Practical implications Both passively and actively morphing blade root chord length and blade taper can be implemented for more economical autonomous helicopter flights. Originality/value Main novelty of our article is simultaneous application of passive and active morphing ideas on helicopter root chord length and blade taper. It is also proved in this study that using both passive and active morphing ideas on helicopter blade root chord and blade taper causes much less energy consumption than using either only passive morphing idea on helicopter blade root chord and blade taper or only active morphing idea on helicopter blade root chord and blade taper. This also reduces fuel consumption and also makes environment cleaner.

Tuning of controller for an aircraft flight control system based on particle swarm optimization

2016 ◽  
Vol 88 (6) ◽  
pp. 799-809 ◽  
Author(s):  
Emre Kiyak
Keyword(s):  
Control System ◽  
Flight Control ◽  
Design Methodology ◽  
Fuzzy Controller ◽  
Fault Detection And Isolation ◽  
Pd Controller ◽  
Flight Control System ◽  
Content Type ◽  
Aircraft Flight ◽  
Aircraft Flight Control

Purpose This study aims to present a method for the conceptual design and simulation of an aircraft flight control system. Design/methodology/approach The design methodology is based on particle swarm optimization (PSO). PSO can be used to improve the performance of conventional controllers. The aim of the present study is threefold. First, it attempts to detect and isolate faults in an aircraft model. Second, it is to design a proportional (P) controller, a proportional derivative (PD) controller, a proportional-integral (PI) controller and a fuzzy controller for an aircraft model. Third, it is to design a PD controller for an aircraft using a PSO algorithm. Findings Conventional controllers, an intelligent controller and a PD controller-based PSO were investigated for flight control. It was seen that the P controller, the PI controller and the PD controller-based PSO caused overshoot. These overshoots were 18.5, 87.7 and 2.6 per cent, respectively. Overshoot was not seen using the PD controller or fuzzy controller. Steady state errors were almost zero for all controllers. The PD controller had the best settling time. The fuzzy controller was second best. The PD controller-based PSO was the third best, but the result was close to the others. Originality/value This study shows the implementation of the present algorithm for a specified space mission and also for study regarding variation of performance parameters. This study shows fault detection and isolation procedures and also controller gain choice for a flight control system. A comparison between conventional controllers and PD-based PSO controllers is presented. In this study, sensor fault detection and isolation are carried out, and, also, root locus, time domain analysis and Routh–Hurwitz methods are used to find the conventional controller gains which differ from other studies. A fuzzy controller is created by the trial and error method. Integral of squared time multiplied by squared error is used as a performance function type in PSO.

The airplane trim system – new functionalities

2020 ◽  
Vol 92 (9) ◽  
pp. 1401-1406
Author(s):  
Cezary Szczepanski ◽  
Mariusz Krawczyk ◽  
Albert Zajdel
Keyword(s):  
Control System ◽  
Flight Control ◽  
Design Methodology ◽  
Hardware In The Loop ◽  
Flight Control System ◽  
Specific Group ◽  
Content Type ◽  
Energy Consuming ◽  
The Common ◽  
Test Scenarios

Purpose A standard automatic flight control system – autopilot – will become required equipment of the future aircraft, operating in the common sky. For a specific group of aircraft, they are too expensive and too energy-consuming solutions. This paper aims to present the concept of an automatic flight control system that overcomes those limitations. Design/methodology/approach The proposed automatic flight control system uses the trim tabs in all prime flight controlling surfaces: elevator, ailerons and rudder, for stabilizing and controlling the steady flights of an aircraft. Findings The results of an aeroplane flight controlled with the use of trim tabs simulation tests and remarks have been presented and discussed. The simulation was conducted in real-time hardware in the loop environment. The stabilization of the flight was achieved in performed test scenarios. Originality/value The possibility to control an aircraft with coordinated deflections of the trimming surfaces is a beneficial alternate to those currently used and can be recommended for use in the next-generation aircraft.

Take-off control and characteristics of FanWing

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Lin Meng ◽  
Yang Gao ◽  
Yangyang Liu ◽  
Shengfang Lu
Keyword(s):  
Control System ◽  
Control Systems ◽  
Design Methodology ◽  
Control System Design ◽  
Control Methods ◽  
Force Analysis ◽  
Close Attention ◽  
Content Type ◽  
Vehicle Load ◽  
Practical Implications

Purpose As a short take-off and landing aircraft, FanWing has the capability of being driven under power a short distance from a parking space to the take-off area. The purpose of this paper is to design the take-off control system of FanWing and study the factors that influence the short take-off performance under control. Design/methodology/approach The force analysis of FanWing is studied in the take-off phase. Two take-off control methods are researched, and several factors that influence the short take-off performance are studied under control. Findings The elevator and fan wing control systems are designed. Although the vehicle load increases under the fan wing control, the fan wing control is not a recommended practice in the take-off phase for its sensitivity to the pitch angle command. The additional pitch-down moment has a significant influence on the control system and the short take-off performance that the barycenter variation of FanWing should be considered carefully. Practical implications The presented efforts provide a reference for the location of the center of gravity in designing FanWing. The traditional elevator control is more recommended than the fan wing control in the take-off phase. Originality/value This paper offers a valuable reference on the control system design of FanWing. It also proves that there is an additional pith-down moment that needs to be paid close attention to. Four factors that influence the short take-off performance are compared under control.

Sensitivity of automatic control of emergency manoeuvre to parametric uncertainty of the airplane model

2019 ◽  
Vol 91 (3) ◽  
pp. 407-419
Author(s):  
Jerzy Graffstein ◽  
Piotr Maslowski
Keyword(s):  
Control System ◽  
Automatic Control ◽  
Flight Control ◽  
Parametric Uncertainty ◽  
Second Phase ◽  
Flight Control System ◽  
Content Type ◽  
Control Quality ◽  
Wide Range ◽  
The Impact

Purpose The main purpose of this work was elaboration and verification of a method of assessing the sensitivity of automatic control laws to parametric uncertainty of an airplane’s mathematical model. The linear quadratic regulator (LQR) methodology was used as an example design procedure for the automatic control of an emergency manoeuvre. Such a manoeuvre is assumed to be pre-designed for the selected airplane. Design/methodology/approach The presented method of investigating the control systems’ sensitivity comprises two main phases. The first one consists in computation of the largest variations of gain factors, defined as differences between their nominal values (defined for the assumed model) and the values obtained for the assumed range of parametric uncertainty. The second phase focuses on investigating the impact of the variations of these factors on the behaviour of automatic control in the manoeuvre considered. Findings The results obtained allow for a robustness assessment of automatic control based on an LQR design. Similar procedures can be used to assess in automatic control arrived at through varying design methods (including methods other than LQR) used to control various manoeuvres in a wide range of flight conditions. Practical implications It is expected that the presented methodology will contribute to improvement of automatic flight control quality. Moreover, such methods should reduce the costs of the mathematical nonlinear model of an airplane through determining the necessary accuracy of the model identification process, needed for assuring the assumed control quality. Originality/value The presented method allows for the investigation of the impact of the parametric uncertainty of the airplane’s model on the variations of the gain-factors of an automatic flight control system. This also allows for the observation of the effects of such variations on the course of the selected manoeuvre or phase of flight. This might be a useful tool for the design of crucial elements of an automatic flight control system.

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.

Environmental implication of the Algerian traditional house

2016 ◽  
Vol 27 (3) ◽  
pp. 338-347 ◽  
Author(s):  
Sabrina Kacher ◽  
Hanane Zermout
Keyword(s):  
Energy Consumption ◽  
Design Methodology ◽  
Vernacular Architecture ◽  
Life Quality ◽  
Environmental Implication ◽  
Content Type ◽  
Environmental Systems ◽  
The World ◽  
To Come ◽  
Practical Implications

Purpose – The control of the environmental impacts of buildings and constructions has certainly progressed in recent years in Europe, but very little in Algeria. The purpose of this paper is to identify and to introduce old environmental systems in the Algerian traditional house which could inspire designers to come up with new constructions with enhanced comfort. Design/methodology/approach – In this work, the authors used the “HQE” French certification grid to gauge the environmental implication of the vernacular architecture. Findings – Environmental systems in the traditional house respect the environment but have to be adapted to the current perception of comfort in order to be applied to the new architecture. Research limitations/implications – The main advantage is that the old environmental systems found in the Algerian traditional houses do not require any machinery to enhance the comfort. Thus they do not need any energy to be useful. Practical implications – As the Canadian Well inspired and influenced the architecture produced around the world to improve the comfort inside the houses, or as the thatched roof which inspired the vegetative roof used today to improve and regulate the energy consumption, the authors hope that some old systems used in the vernacular architecture will inspire architects or regular people who would like to enhance their comfort and life quality. Originality/value – Passive solutions used to improve comfort, with reduced energy consumption in houses, are increasingly sought all around the world. This work can play a part in introducing some environmental solutions used in the vernacular architecture which are nowadays left aside.

Fuzzy robust fault estimation scheme for fault tolerant flight control systems based on unknown input observer

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Gulay Unal
Keyword(s):  
Fuzzy Logic ◽  
Control System ◽  
Fault Detection ◽  
Flight Control ◽  
Fault Tolerant ◽  
Fault Isolation ◽  
Fault Detection And Isolation ◽  
Sensor Faults ◽  
Flight Control System ◽  
Content Type

Purpose The purpose of this study is to present a new integrated structure for a fault tolerant aircraft control system because fault diagnosis of flight control systems is extremely important in obtaining healthy flight. An approach to detect and isolate aircraft sensor faults is proposed, and a new integrated structure for a fault tolerant aircraft control system is presented. Design/methodology/approach As disturbance and sensor faults are mixed together in a flight control system, it is difficult to isolate any fault from the disturbance. This paper proposes a robust unknown input observer for state estimation and fault detection as well as isolation using fuzzy logic. Findings The dedicated observer scheme (DOS) and generalized observer scheme (GOS) are used for fault detection and isolation in an observer-based approach. Using the DOS, it has been shown through simulation that sensor fault detection and isolation can be made, but here the threshold value must be well chosen; if not, the faulty sensor cannot be correctly isolated. On the other hand, the GOS is more usable and flexible than the DOS and allows isolation of faults more correctly and for a fuzzy logic-based controller to be used to realize fault isolation completely. Originality/value The fuzzy logic approach applied to the flight control system adds an important key for sensor fault isolation because it reduces the effect of false alarms and allows the identification of different kinds of sensor faults. The proposed approach can be used for similar systems.

Three biomimetic flight control sensors

2014 ◽  
Vol 2 (1) ◽  
pp. 27-39 ◽  
Author(s):  
Javaan Chahl
Keyword(s):  
Optical Flow ◽  
Control Systems ◽  
Flight Control ◽  
Design Methodology ◽  
Urban Environments ◽  
Insect Vision ◽  
Content Type ◽  
Heading Control ◽  
First Time ◽  
Practical Implications

Purpose – Insects depend on the spatial, temporal and spectral distribution of light in the environment for navigation, collision avoidance and flight control. The principles of insect vision have been gradually revealed over the course of decades by biological scientists. The purpose of this paper is to report on bioinspired implementations and flight tests of these sensors and reflexes on unmanned aerial vehicles (UAVs). The devices are used for the stabilization of UAVs in attitude, heading and position. The implementations were developed to test the hypothesis that current understanding of insect optical flight control systems is feasible in real systems. Design/methodology/approach – Design was based on behavioral and anatomical studies of insects. The approach taken was to test the designs in flight on a UAV. Findings – The research showed that stabilization in attitude, heading and position is possible using the developed sensors. Practical implications – Partial alternatives to magnetic, inertial and GPS sensing have been demonstrated. Optical flow and polarization compassing are particularly relevant to flight in urban environments and in planetary exploration. Originality/value – For the first time the use of multispectral horizon sensing, polarization compassing and optical flow-based heading control have been demonstrated in flight.

scholarly journals Effect of the Simultaneous Variation in Blade Root Chord Length and Blade Taper on Helicopter Flight Control Effort

2017 ◽  
Vol 2017 ◽  
pp. 1-8 ◽  
Author(s):  
Tugrul Oktay ◽  
Firat Sal
Keyword(s):  
Flight Control ◽  
Closed Loop ◽  
Chord Length ◽  
Essential Dynamics ◽  
Flight Control System ◽  
Control Effort ◽  
Blade Root ◽  
Helicopter Flight ◽  
Output Variance ◽  
Simultaneous Variation

In this study, the effect of simultaneous variation in blade root chord length and blade taper on the control effort of helicopter flight control system (i.e., FCS) of a helicopter is investigated. Therefore, helicopter models (i.e., complex, control-oriented, and physics-based models) including the main physics and essential dynamics are used. The effect of simultaneous variation in the blade root chord length and blade taper (i.e., in both chordwise and lengthwise directions dependently) on the control effort of an FCS of a helicopter and also on the closed-loop responses is studied. Comparisons in terms of the control effort and peak values with and without variations in the blade root chord and blade taper changes are carried out. For helicopter FCS variance-constrained controllers, specific output variance-constrained controllers are beneficial.

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