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Article
Publication date: 1 August 2000

George G. Kapadoukas and Andrew Self

An essential part of the validation process of flight simulators has been the comparison of the simulator and aeroplane flight modes of motion for set manoeuvres. A…

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Abstract

An essential part of the validation process of flight simulators has been the comparison of the simulator and aeroplane flight modes of motion for set manoeuvres. A simulator‐to‐flight match is essential for the full range of manoeuvres, both in‐flight and on‐the‐ground, if the simulator is to be used for all usual and unusual scenarios. This is particularly true in ground level manoeuvres where data are not available and pilots need to be trained for situations that are too dangerous to practise in real aircraft and too important to neglect. Aircraft in‐flight modes are used to verify simulator behaviour. However, ground‐contact – an important part of pilot training – modes are not used to verify fidelity. A full systems approach is discussed and a taxonomy of in‐flight and ground‐contact modes provided for the full range of operations, from brakes‐off through taxiing, take‐off, landing and parking. The full taxonomy of modes is needed to ensure that the dynamic behaviour of the simulator is realistic for all in‐flight and ground‐contact scenarios and thereby ensure that the training is realistic for the full range of conventional and dangerous manoeuvres.

Details

Aircraft Engineering and Aerospace Technology, vol. 72 no. 4
Type: Research Article
ISSN: 0002-2667

Keywords

Article
Publication date: 12 February 2019

S. Abolfazl Mokhtari and Mehdi Sabzehparvar

The paper aims to present an innovative method for identification of flight modes in the spin maneuver, which is highly nonlinear and coupled dynamic.

Abstract

Purpose

The paper aims to present an innovative method for identification of flight modes in the spin maneuver, which is highly nonlinear and coupled dynamic.

Design/methodology/approach

To fix the mode mixing problem which is mostly happen in the EMD algorithm, the authors focused on the proposal of an optimized ensemble empirical mode decomposition (OEEMD) algorithm for processing of the flight complex signals that originate from FDR. There are two improvements with the OEEMD respect to the EEMD. First, this algorithm is able to make a precise reconstruction of the original signal. The second improvement is that the OEEMD performs the task of signal decomposition with fewer iterations and so with less complexity order rather than the competitor approaches.

Findings

By applying the OEEMD algorithm to the spin flight parameter signals, flight modes extracted, then with using systematic technique, flight modes characteristics are obtained. The results indicate that there are some non-standard modes in the nonlinear region due to couplings between the longitudinal and lateral motions.

Practical implications

Application of the proposed method to the spin flight test data may result accurate identification of nonlinear dynamics with high coupling in this regime.

Originality/value

First, to fix the mode mixing problem in EMD, an optimized ensemble empirical mode decomposition algorithm is introduced, which disturbed the original signal with a sort of white Gaussian noise, and by using white noise statistical characteristics the OEEMD fix the mode mixing problem with high precision and fewer calculations. Second, by applying the OEEMD to the flight output signals and with using the systematic method, flight mode characteristics which is very important in the simulation and controller designing are obtained.

Details

Aircraft Engineering and Aerospace Technology, vol. 91 no. 4
Type: Research Article
ISSN: 1748-8842

Keywords

Article
Publication date: 26 April 2013

He Xu and Yi‐ping Shen

Target tracking systems are generally computationally intensive and require expensive and power‐hungry visual sensors. On the other hand, the existing target tracking control…

Abstract

Purpose

Target tracking systems are generally computationally intensive and require expensive and power‐hungry visual sensors. On the other hand, the existing target tracking control approaches fail to track the target swiftly and accurately when the mobile robot moves in the diversified manoeuvre modes. The purpose of this paper is to propose a novel target tracking control method with a low cost embedded vision system to achieve high accuracy and speediness of target tracking control, regardless of the type of manoeuvre modes.

Design/methodology/approach

The pan/tilt angle differences are transformed from the tracking error between the image centre and the coordinates of the target centroid returned by the CMUcam3; the corresponding pan/tilt angle variation rates are calculated based on the manoeuvre control. All of them are fed to the controller. Then the controller generates appropriate control signals to fit the changing speed of target centroid and compensate for the tracking error. The experiments are designed in a way that the CMUcam3 keeps the target centre coincident with the image centre when the mobile robot moves in the diversified manoeuvre modes.

Findings

In spite of the type of manoeuvre modes, the controller responds to the tracking error instantly and actuates the pan/tilt with suitable position and speed commands, and the target centroid remains in the bounding box during the entire movement.

Originality/value

The proposed target tracking control takes the correlation between the robot manoeuvre modes and the target tracking control into account, and particularly suits for the target tracking tasks in planetary exploration, surveillance and military applications.

Details

Industrial Robot: An International Journal, vol. 40 no. 3
Type: Research Article
ISSN: 0143-991X

Keywords

Article
Publication date: 1 June 1969

THE automatic flight control system (AFCS) for the Concorde has been jointly developed by Elliott‐Automation Ltd. and SFENA (Société Francaise pour la Navigation Aérienne) for the…

Abstract

THE automatic flight control system (AFCS) for the Concorde has been jointly developed by Elliott‐Automation Ltd. and SFENA (Société Francaise pour la Navigation Aérienne) for the production aircraft. Elliott carry the overall design responsibility and the equipment will be supported in the field by both Elliott and SFENA. The pitch axis of the autopilot and flight director, the autothrottle, all aspects of the control of speed, all pilot/ AFCS interfaces and the landing display are Elliott responsibilities for the pre‐production and production aircraft, while SFENA are responsible for the three‐axis autostabiliser, azimuth axes of the autopilot and flight director, electric trim system and the flight test instrumentation for the AFCS. The Bendix Corporation participated in the programme for the prototype aircraft with the design and manufacture of the azimuth axes of the autopilot and flight director, and the electric trim system.

Details

Aircraft Engineering and Aerospace Technology, vol. 41 no. 6
Type: Research Article
ISSN: 0002-2667

Article
Publication date: 3 May 2013

Davood Asadi, Mahdi Sabzehparvar and Heidar Ali Talebi

Understanding the performance and flight envelope of a damaged aircraft is a preliminary requirement to recover the aircraft after damage. This paper aims to provide a…

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Abstract

Purpose

Understanding the performance and flight envelope of a damaged aircraft is a preliminary requirement to recover the aircraft after damage. This paper aims to provide a comprehensive understanding of wing damage effect on airplane performance, local stability, and flying quality of each trim state inside the achievable flight envelope.

Design/methodology/approach

This paper demonstrates the use of attainable equilibrium points which are referred as trim states in order to estimate a damaged airplane manoeuvring flight envelope using a numerical computation method.

Findings

Wing damaged airplane manoeuvring flight envelope is estimated for different portions of the wing tip loss. Local stability at each trim condition inside the estimated flight envelope is analysed, and also motion flight modes and flying quality sensitivity to the wing damage are explored.

Originality/value

Local stability and flying quality analysis at each trim condition inside the flight envelope which demonstrate the effect of damage provides a criterion to prioritize the choice of trimmed flight condition as motion primitives for the airplane post‐damage flight and safe landing.

Details

Aircraft Engineering and Aerospace Technology, vol. 85 no. 3
Type: Research Article
ISSN: 0002-2667

Keywords

Article
Publication date: 8 February 2016

Antonio Mazzaracchio

This paper aims to address a significant issue related to the coupled and uncoupled treatment of the thermal and dynamic problems in the optimization of aeroassisted orbital…

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Abstract

Purpose

This paper aims to address a significant issue related to the coupled and uncoupled treatment of the thermal and dynamic problems in the optimization of aeroassisted orbital maneuvers and the simultaneous optimal sizing of the associated heat shields. The literature generally focuses on decoupled treatments that reduce the computational load; in this manner, consequently, a decrease in the representativity of the solution manifests. The general operating mode first optimizes the trajectory and subsequently defines the optimal heat shield design based on that trajectory.

Design/methodology/approach

This paper analyzes the impact of both treatments on the evaluation of the convenience of an aeroassisted maneuver with respect to an equivalent purely propulsive exoatmospheric maneuver in relation to the achievable total mass savings of the propellant and the heat shield. Two case studies are analyzed via an optimization methodology that references genetic algorithms: the first case study is related to an aerobraking maneuver and the second case study is related to an orbital plane change.

Findings

The results demonstrate that the adoption of decoupling produces conservative solutions, i.e. unfavorable estimates, with a lower level of convenience of the aeroassisted technique compared to equivalent purely propulsive exoatmospheric maneuvers.

Originality/value

This type of analysis can provide an appropriate discernment criterion for the selection of the modus operandi based on the available computational power and the desired level of representativity.

Details

World Journal of Engineering, vol. 13 no. 1
Type: Research Article
ISSN: 1708-5284

Keywords

Article
Publication date: 26 July 2021

Hongxing Zheng, Xin Liu, Junhui Wu, Yiyun Man, Xibao Xu and Jifeng Guo

The purpose of this paper is to improve the efficiency of on-orbit operations through the top-level task design based on DoDAF. Based on the existing upper stage rocket…

Abstract

Purpose

The purpose of this paper is to improve the efficiency of on-orbit operations through the top-level task design based on DoDAF. Based on the existing upper stage rocket technology, orbit transfer vehicles (OTVs) have developed rapidly in recent years. However, the lack of decision guidance based on overall task analysis requires integrating top-level analysis and bottom-level execution to achieve the smooth development of full-process tasks.

Design/methodology/approach

Using the Department of Defense Architecture Framework (DoDAF) as a reference, this paper performs the top-level mission analysis modeling of the on-orbit rendezvous and capture of the OTV. Moreover, the typical operational view products are obtained, and the cooperative relations among the mission requirements, the system requirements, and the functional requirements are also analyzed.

Findings

The results show that the attitude of the OTV changes violently during the maneuver and rendezvous phases. In addition, the view products can be optimized based on the results.

Originality/value

The proposed DoDAF-based on-orbit task integration analysis method achieves the effective fusion of high-level analysis and bottom-level execution of OTV on-orbit rendezvous and capture task through the top-level task modeling, operation view generation and task relationship analysis. According to the requirements and constraints of the on-orbit rendezvous and capture task, the control instructions of the vehicle are efficiently generated under the DoDAF framework.

Details

Aircraft Engineering and Aerospace Technology, vol. 93 no. 6
Type: Research Article
ISSN: 1748-8842

Keywords

Article
Publication date: 1 May 1974

THE airframe systems division of Lucas Aerospace are involved in producing the high lift and wing sweep control unit for which the design rights are shared with Microtecnica SpA…

Abstract

THE airframe systems division of Lucas Aerospace are involved in producing the high lift and wing sweep control unit for which the design rights are shared with Microtecnica SpA who hold the contract.

Details

Aircraft Engineering and Aerospace Technology, vol. 46 no. 5
Type: Research Article
ISSN: 0002-2667

Article
Publication date: 28 May 2021

Zhiwen Hou and Fanliang Bu

The purpose of this study is to establish an effective tracking algorithm for small unmanned aerial vehicles (UAVs) based on interacting multiple model (IMM) to take timely…

Abstract

Purpose

The purpose of this study is to establish an effective tracking algorithm for small unmanned aerial vehicles (UAVs) based on interacting multiple model (IMM) to take timely countermeasures against illegal flying UAVs.

Design/methodology/approach

In this paper, based on the constant velocity model (CV), the maneuvering adaptive current statistical model (CS) and the angular velocity adaptive three-dimensional (3D) fixed center constant speed rate constant steering rate model, a small UAV tracking algorithm based on adaptive interacting multiple model (AIMM-UKF) is proposed. In addition, an adaptive robust filter is added to each model of the algorithm. The linear Kalman filter algorithm is attached to the CV model and the CS model and the unscented Kalman filter algorithm (UKF) is attached to the CSCDR model to solve the nonlinearity of the 3D turning model.

Findings

Monte-Carlo simulation comparison with the other two IMM tracking algorithms shows that in the case of different movement modes and maneuvering strength of the UAV, the AIMM-UKF algorithm makes a good trade-off between the amount of calculation and filtering accuracy, which can maintain more accurate and stable tracking and has strong robustness. At the same time, after testing the actual observation data of the UAV, the results show that the AIMM-UKF algorithm state estimation trajectory can be regarded as an actual trajectory in practical engineering applications, which has good practical value.

Originality/value

This paper presents a new small UAV tracking algorithm based on IMM and the advantages and practicability of this algorithm compared with existing algorithms are proved through experiments.

Details

Aircraft Engineering and Aerospace Technology, vol. 93 no. 4
Type: Research Article
ISSN: 1748-8842

Keywords

Article
Publication date: 28 June 2011

David Sanders, Giles Tewkesbury, Ian J. Stott and David Robinson

The purpose of this paper is to investigate how to make tele‐operated tasks easier using an expert system to interpret joystick and sensor data.

Abstract

Purpose

The purpose of this paper is to investigate how to make tele‐operated tasks easier using an expert system to interpret joystick and sensor data.

Design/methodology/approach

Current tele‐operated systems tend to rely heavily on visual feedback and experienced operators. Simple expert systems improve the interaction between an operator and a tele‐operated mobile‐robot using ultrasonic sensors. Systems identify potentially hazardous situations and recommend safe courses of action. Because pairs of tests and results took place, it was possible to use a paired‐samples statistical test.

Findings

Results are presented from a series of timed tasks completed by tele‐operators using a joystick to control a mobile‐robot via an umbilical cable. Tele‐operators completed tests both with and without sensors and with and without the new expert system and using a recently published system to compare results. The t‐test was used to compare the means of the samples in the results.

Research limitations/implications

Time taken to complete a tele‐operated task with a mobile‐robot partly depends on how a human operator interacts with the mobile‐robot. Information about the environment was restricted and more effective control of the mobile‐robot could have been achieved if more information about the environment had been available, especially in tight spaces. With more information available for analysis, the central processor could have had tighter control of robot movements. Simple joysticks were used for the test and they could be replaced by more complicated haptic devices. Finally, each individual set of tests was not necessarily statistically significant so that caution was required before generalising the results.

Practical implications

The new systems described here consistently performed tasks more quickly than simple tele‐operated systems with or without sensors to assist. The paper also suggests that the amount of sensor support should be varied depending on circumstances. The paired samples test was used because people (tele‐operators) were inherently variable. Pairing removed much of that random variability. When results were analysed using a paired‐samples statistical test then results were statistically significant. The new systems described in this paper were significantly better at p<0.05 (95 per cent probability that this result would not occur by chance alone).

Originality/value

The paper shows that the new system performed every test faster on average than a recently published system used to compare the results.

Details

Sensor Review, vol. 31 no. 3
Type: Research Article
ISSN: 0260-2288

Keywords

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