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Article
Publication date: 10 May 2013

Takuma Hino and Takeshi Tsuchiya

The purpose of this research is to propose a novel method to plan paths of unmanned aerial vehicle (UAV) formations. This is to make use of the aerodynamic advantage of formation

Abstract

Purpose

The purpose of this research is to propose a novel method to plan paths of unmanned aerial vehicle (UAV) formations. This is to make use of the aerodynamic advantage of formation flight to reduce energy consumption of UAVs.

Design/methodology/approach

The method proposed in this research make use of the fact that, under certain conditions, the regions where if a UAV rendezvous or separates with another UAV would save energy by formation flying can be analytically calculated. The intersections of these regions are used to decide which UAV are to fly in the same formation. This combination of which UAV are to fly together and what order they join/part from the formation is called the topology of the problem.

Findings

The proposed method was proved to be effective in identifying efficient topologies, with the majority of the topologies selected falling below 5 percent error rate in terms of energy.

Originality/value

The originality of this research lies in the fact that the proposed method is completely visualised – all the necessary information to organise formations is visualised in the envelopes. Still, the proposed method was proved to be effective in selecting efficient topologies.

Details

International Journal of Intelligent Unmanned Systems, vol. 1 no. 2
Type: Research Article
ISSN: 2049-6427

Keywords

Article
Publication date: 2 October 2017

Zhaohui Dang, Li Fan, Zhaokui Wang and Yulin Zhang

The purpose of this paper is to present the obtained analytic solutions of maximal and minimal inter-satellite distances for flying-around satellite formation.

Abstract

Purpose

The purpose of this paper is to present the obtained analytic solutions of maximal and minimal inter-satellite distances for flying-around satellite formation.

Design/methodology/approach

The relative motion equation is used to express the inter-satellite distance as the function of the orbital elements of two participating satellites for the flying-around satellite formation. Then by taking the derivative of the distance function with respect to the true anomaly, some possible extreme value points are obtained. According to the detailed analysis, the maximal and minimal distance solutions are found. By a reverse process, the expected initial differential orbital elements that generate the required extreme inter-satellite distances are also obtained.

Findings

The maximal and minimal distances of the flying-around formation can be analytically written as the functions of three initial orbital elements differences, i.e. the differential orbital inclination, the differential eccentricity and the differential right ascension. For the given maximal and minimal distances, there are lots of solutions of the initial differential orbital elements, which can produce the expected relative motions.

Research limitations/implications

The solutions of the maximal and minimal inter-satellite distances are only accurate for the circular or near circular reference orbit. For the elliptic reference orbit, there is a need to develop new methods to find the analytic solutions.

Practical implications

The results here can be applied to design the factual flying-around formation with dimension requirements in mission analysis stage.

Originality/value

By using the solutions presented in this paper, the engineers can design the expected flying-around formation with required maximal and minimal inter-satellite distances in a very easy way.

Details

Aircraft Engineering and Aerospace Technology, vol. 89 no. 6
Type: Research Article
ISSN: 1748-8842

Keywords

Article
Publication date: 3 January 2017

Xiaowei Shao, Jihe Wang, Dexin Zhang and Junli Chen

The purpose of this paper is to propose a modified fuel-balanced formation keeping strategy based on actively rotating satellites in the formation in the J2 perturbed environment.

Abstract

Purpose

The purpose of this paper is to propose a modified fuel-balanced formation keeping strategy based on actively rotating satellites in the formation in the J2 perturbed environment.

Design/methodology/approach

Based on the relative orbital elements theory, the J2 perturbed relative motions between different satellites in the formation are analyzed, and then, the method to estimate fuel required to keep the in-plane and out-of-plane relative motions is presented, based on which a modified fuel-balanced formation keeping strategy is derived by considering both in-plane and out-of-plane J2 perturbations.

Findings

Numerical simulations demonstrate that the modified fuel-balanced formation keeping strategy is valid, and the modified fuel-balanced formation keeping strategy requires less total fuel consumption than original Vadali and Alfriend’s method.

Research limitations/implications

The modified fuel-balanced formation keeping strategy is valid for formation flying mission whose member satellite is in circular or near-circular orbit.

Practical implications

The modified fuel-balanced formation keeping strategy can be used to solve formation flying keeping problem, which involves multiple satellites in the formation.

Originality/value

The modified fuel-balanced formation keeping strategy is proposed by considering both in-plane and out-of-plane J2 perturbations, which further reduce the fuel consumption than the original Vadali and Alfriend’s method.

Details

Aircraft Engineering and Aerospace Technology, vol. 89 no. 1
Type: Research Article
ISSN: 1748-8842

Keywords

Article
Publication date: 2 May 2017

Wenjing Zhu, Dexin Zhang, Jihe Wang and Xiaowei Shao

The purpose of this paper is to present a novel high-precision relative navigation method for tight formation-keeping based on thrust on-line identification.

Abstract

Purpose

The purpose of this paper is to present a novel high-precision relative navigation method for tight formation-keeping based on thrust on-line identification.

Design/methodology/approach

Considering that thrust acceleration cannot be measured directly, an on-line identification method of thrust acceleration is explored via the estimated acceleration of major space perturbation and the inter-satellite relative states obtained from space-borne acceleration sensors; then, an effective identification model is designed to reconstruct thrust acceleration. Based on the identified thrust acceleration, relative orbit dynamics for tight formation-keeping is established. Further, using global positioning system (GPS) measurement information, a modified extended Kalman filter (EKF) is suggested to obtain the inter-satellite relative position and relative velocity.

Findings

Compared with the normal EKF and the adaptive robust EKF, the proposed modified EKF has better estimation accuracy in radial and along-track directions because of accurate compensation of thrust acceleration. Meanwhile, high-precision relative navigation results depend on high-precision acceleration sensors. Finally, simulation studies on a chief-deputy formation flying control system are performed to verify the effectiveness and superiority of the proposed relative navigation algorithm.

Social implications

This paper provides a reference in solving the problem of high-precision relative navigation in tight formation-keeping application.

Originality/value

This paper proposes a novel on-line identification method for thrust acceleration and shows that thrust identification-based modified EKF is more efficient in relative navigation for tight formation-keeping.

Details

Aircraft Engineering and Aerospace Technology, vol. 89 no. 3
Type: Research Article
ISSN: 1748-8842

Keywords

Article
Publication date: 2 October 2018

Jihe Wang, Dexin Zhang, GuoZhong Chen and Xiaowei Shao

The purpose of this paper is to propose a new fuel-balanced formation keeping reference trajectories planning method based on selecting the virtual reference center(VRC) in a…

Abstract

Purpose

The purpose of this paper is to propose a new fuel-balanced formation keeping reference trajectories planning method based on selecting the virtual reference center(VRC) in a fuel-balanced sense in terms of relative eccentricity and inclination vectors (E/I vectors).

Design/methodology/approach

By using the geometrical intuitive relative E/I vectors theory, the fuel-balanced VRC selection problem is reformulated as the geometrical problem to find the optimal point to equalize the distances between the VRC and the points determined by the relative E/I vectors of satellites in relative E/I vectors plane, which is solved by nonlinear programming method.

Findings

Numerical simulations demonstrate that the new proposed fuel-balanced formation keeping strategy is valid, and the new method achieves better fuel-balanced performance than the traditional method, which keeps formation with respect to geometrical formation center.

Research limitations/implications

The new fuel-balanced formation keeping reference trajectories planning method is valid for formation flying mission whose member satellite is in circular or near circular orbit in J2 perturbed orbit environment.

Practical implications

The new fuel-balanced formation keeping reference trajectories planning method can be used to solve formation flying keeping problem, which involves multiple satellites in the formation.

Originality/value

The fuel-balanced reference trajectories planning problem is reformulated as a geometrical problem, which can provide insightful way to understand the dynamic nature of the fuel-balanced reference trajectories planning issue.

Details

Aircraft Engineering and Aerospace Technology, vol. 90 no. 6
Type: Research Article
ISSN: 1748-8842

Keywords

Article
Publication date: 6 June 2008

Christie Alisa Maddock and Massimiliano Vasile

The purpose of this paper is to present a methodology and experimental results on using global optimization algorithms to determine the optimal orbit, based on the mission…

Abstract

Purpose

The purpose of this paper is to present a methodology and experimental results on using global optimization algorithms to determine the optimal orbit, based on the mission requirements, for a set of spacecraft flying in formation with an asteroid.

Design/methodology/approach

A behavioral‐based hybrid global optimization approach is used to first characterize the solution space and find families of orbits that are a fixed distance away from the asteroid. The same optimization approach is then used to find the set of Pareto optimal solutions that minimize both the distance from the asteroid and the variation of the Sun‐spacecraft‐asteroid angle. Two sample missions to asteroids, representing constrained single and multi‐objective problems, were selected to test the applicability of using an in‐house hybrid stochastic‐deterministic global optimization algorithm (Evolutionary Programming and Interval Computation (EPIC)) to find optimal orbits for a spacecraft flying in formation with an orbit. The Near Earth Asteroid 99942 Apophis (2004 MN4) is used as the case study due to a fly‐by of Earth in 2029 leading to two potential impacts in 2036 or 2037. Two black‐box optimization problems that model the orbital dynamics of the spacecraft were developed.

Findings

It was found for the two missions under test, that the optimized orbits fall into various distinct families, which can be used to design multi‐spacecraft missions with similar orbital characteristics.

Research limitations/implications

The global optimization software, EPIC, was very effective at finding sets of orbits which met the required mission objectives and constraints for a formation of spacecraft in proximity of an asteroid. The hybridization of the stochastic search with the deterministic domain decomposition can greatly improve the intrinsic stochastic nature of the multi‐agent search process without the excessive computational cost of a full grid search. The stability of the discovered families of formation orbit is subject to the gravity perturbation of the asteroid and to the solar pressure. Their control, therefore, requires further investigation.

Originality/value

This paper contributes to both the field of space mission design for close‐proximity orbits and to the field of global optimization. In particular, suggests a common formulation for single and multi‐objective problems and a robust and effective hybrid search method based on behaviorism. This approach provides an effective way to identify families of optimal formation orbits.

Details

International Journal of Intelligent Computing and Cybernetics, vol. 1 no. 2
Type: Research Article
ISSN: 1756-378X

Keywords

Article
Publication date: 1 August 2001

Colin R. McInnes

A range of space systems engineering technologies are currently under development at the University of Glasgow. Much of this work centres on advanced propulsion (solar sailing and…

Abstract

A range of space systems engineering technologies are currently under development at the University of Glasgow. Much of this work centres on advanced propulsion (solar sailing and tethers) which is complemented by studies on space robotics and spacecraft autonomy. This paper summarises these activities to provide a brief overview of current research interests. Although some work represents fundamental research in space systems engineering, much is mission‐oriented and focused on future exploitation.

Details

Aircraft Engineering and Aerospace Technology, vol. 73 no. 4
Type: Research Article
ISSN: 0002-2667

Keywords

Article
Publication date: 11 October 2018

Yaolong Liu and Yaoming Zhou

The purpose of this paper is to study the potential advantages of aircraft formation flight (FF) and to exploit further benefits through exchanging the leading positions.

Abstract

Purpose

The purpose of this paper is to study the potential advantages of aircraft formation flight (FF) and to exploit further benefits through exchanging the leading positions.

Design/methodology/approach

The detailed and robust methodologies concerning FF mission analysis including the leading aircraft rotation strategies are developed in this paper to study the fuel burn benefit and the additional bonus of formation rotation.

Findings

Switch of FF leading positions can offset the undesired weight ratios between the leading and trailing aircraft within FF missions, which further alleviates the deviations from design flight conditions. The case studies on two long-range civil transport aircraft in FF show that the leading and trailing aircraft can achieve almost equal fuel benefit through rotations. As compared to FF without rotation, the fuel efficiency can be improved by more than 11 per cent.

Research limitations/implications

The work can bring benefit the research communities as a fundamental basis for operational studies of FF, such as FF airspace management in the future, which is significant for a future real-world implementation of FFs.

Practical implications

According to the authors’ study, equal or quasi-equal fuel savings can be achieved if the rotation is properly arranged. For the real-world FF application, fuel consumption (FC) or cost redistribution problem for leading and trailing aircraft belonging to two different operating airlines can therefore be resolved through the concept proposed by the paper.

Originality/value

The methods developed in the paper have the advantage to give more reliable estimations of the achievable fuel burn savings of FF. The concept proposed in the paper has significant meaning with respect to offset the undesired weight ratios between the leading and trailing aircraft within FF missions and redistributing FC or cost redistribution of different operating airlines.

Details

Aircraft Engineering and Aerospace Technology, vol. 90 no. 9
Type: Research Article
ISSN: 1748-8842

Keywords

Article
Publication date: 12 September 2008

Blanca C. Garcia

Inscribed in third generation KM schemes, this paper aims to collect the resulting experience of facilitating an international consultation process on knowledge‐city topics

1020

Abstract

Purpose

Inscribed in third generation KM schemes, this paper aims to collect the resulting experience of facilitating an international consultation process on knowledge‐city topics, called the Most Admired Knowledge City (MAKCi) Awards.

Design/methodology/approach

The paper draws together the experiences gained through facilitating an international consultation process.

Findings

The paper reports on observations of the MAKCi point of convergence within the knowledge‐based development (KBD) community. It recounts the experience of a group of KBD experts who have undertaken a learning journey into knowledge‐generative collaborative research. Linked to a globally based community of practice, the MAKCi exercise clearly fosters a research and learning space through a network of practice (NoP) within the greater global KBD community that is worth exploring from multiple standpoints.

Originality/value

The paper discovers how knowledge‐intensive research work could depend on community links and networks to gain the necessary perspectives and paths to learn and make sense of the changing world. The MAKCi exercise appears a challenging case of networked knowledge‐sharing experience through a connected expertise that brings a group of individuals together to create integrated knowledge, regardless of geographical or time constraints. The second part of the paper concentrates on bringing further understanding as to how learning and knowledge creation is possible through networks, by conveying higher levels of knowledge co‐creation at a global scale, so relevant in knowledge‐based development contexts. The paper advances some applications on how emerging models of knowledge‐intensive networks such as NoPs foster tacit knowledge conversion into explicit scholarly knowledge.

Details

Journal of Knowledge Management, vol. 12 no. 5
Type: Research Article
ISSN: 1367-3270

Keywords

Article
Publication date: 29 June 2012

Wei Zhang, Zhongmin Deng and Jingsheng Li

The purpose of this paper is to propose strategies for satellite cluster non‐coplanar orbit transfer to reduce fuel cost of formation maintenance and orbit maneuver.

Abstract

Purpose

The purpose of this paper is to propose strategies for satellite cluster non‐coplanar orbit transfer to reduce fuel cost of formation maintenance and orbit maneuver.

Design/methodology/approach

This research tries to use geometric method model to describe the relative motion of satellites in the cluster non‐coplanar orbit transfer, and genetic algorithm (GA) to optimize the proposed maneuver strategies.

Findings

Compared with the C‐W equations, the geometric method model is found to be more precise. Three strategies are proposed and optimized to maintain the relative orbit and a strategy of indefinite phase and non‐synchronous costs least fuel.

Practical implications

Geometric method model can be used to describe the relative motion of satellite cluster, especially on elliptical orbits considering the effects of perturbation, with a simple form and good accuracy. Fuel cost minimization is one of the most important issues in formation flight mission.

Originality/value

This paper provides dynamics analysis about formation non‐coplanar orbit transfer, which is involved in minor researches.

Details

Aircraft Engineering and Aerospace Technology, vol. 84 no. 4
Type: Research Article
ISSN: 0002-2667

Keywords

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