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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: 7 September 2015

Xiaowei Shao, Mingxuan Song, Dexin Zhang and Ran Sun

The purpose of this paper is to present a method to conduct small satellite rendezvous mission by using the differential aerodynamic forces under J2 perturbation in low…

Abstract

Purpose

The purpose of this paper is to present a method to conduct small satellite rendezvous mission by using the differential aerodynamic forces under J2 perturbation in low earth orbit (LEO).

Design/methodology/approach

Each spacecraft is assumed to be equipped with two large flat plates, which can be controlled for generating differential accelerations in all three directions. Based on the kinetic theory, the aerodynamic lift and drag generated by a flat plate are calculated. To describe the relative dynamics under J2 perturbation, a modified model is derived from the high-fidelity linearized J2 equations proposed by Schweighart and Sedwick.

Findings

Simulation results demonstrate that the proposed method is valid and efficient to solve satellite rendezvous problem, and the modified model considering J2 effect shows better accuracy than the Horsley’s Clohessy–Wiltshire-based model.

Research limitations/implications

Because aerodynamic force will reduce drastically as orbital altitude rises, the rendezvous control strategy for small satellites presented in this paper should be limited to the scenarios when satellites are in LEO.

Practical implications

The rendezvous control method in this paper can be applied to solve satellite rendezvous maneuver problem for small satellites in LEO.

Originality/value

This paper proposes a modified differential aerodynamic control model by considering J2 perturbation, and simulation results show that it can achieve higher rendezvous control accuracy.

Details

Aircraft Engineering and Aerospace Technology: An International Journal, vol. 87 no. 5
Type: Research Article
ISSN: 0002-2667

Keywords

Article
Publication date: 29 June 2012

Jihe Wang, Xibin Cao and Jinxiu Zhang

The purpose of this paper is to propose a fuel‐optimal virtual centre selection method for formation flying maintenance in the J2 perturbed environment.

Abstract

Purpose

The purpose of this paper is to propose a fuel‐optimal virtual centre selection method for formation flying maintenance in the J2 perturbed environment.

Design/methodology/approach

Based on the relative orbital elements (ROE) theory, the J2 perturbed relative motions between different satellites in the formation are analyzed, and then the fuel‐optimal virtual centre selection issue for formation flying maintenance are parameterized in terms of ROE. In order to determine the optimal virtual centre, two theories are proposed in terms of ROE.

Findings

Numerical simulations demonstrate that the fuel‐optimal virtual centre selection method is valid, and the control of the ROE of each satellite with respect to a virtual optimal centre of the formation is more efficient regarding the fuel consumption than the control of all satellites with respect to a satellite belonging to the formation.

Research limitations/implications

The fuel‐optimal virtual centre selection method is valid for formation flying mission whose member satellite in circular or near circular orbit.

Practical implications

The fuel‐optimal virtual centre selection approach can be used to solve formation flying maintenance problem which involves multiple satellites in the formation.

Originality/value

The paper proposes a fuel‐optimal virtual centre selection method in terms of ROE, and shows that keeping the formation with respect the optimal virtual centre is more fuel efficient.

Details

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

Keywords

Article
Publication date: 3 January 2017

Xiaowei Shao, Mingxuan Song, Jihe Wang, Dexin Zhang and Junli Chen

The purpose of this paper is to present a method to achieve small satellite formation keeping operations by using the differential lift and drag to control the drift…

Abstract

Purpose

The purpose of this paper is to present a method to achieve small satellite formation keeping operations by using the differential lift and drag to control the drift caused by J2 perturbation in circular or near-circular low earth orbits (LEOs).

Design/methodology/approach

Each spacecraft is equipped with five large flat plates, which can be controlled to generate differential accelerations. The aerodynamic lift and drag acting on a flat plate is calculated by the kinetic theory. To maintain the formation within tracking error bounds in the presence of J2 perturbation, a nonlinear Lyapunov-based feedback control law is designed.

Findings

Simulation results demonstrate that the proposed method is efficient for the satellite formation keeping and better accuracy advantage in comparison with classical approaches via the fixed maximum differential aerodynamic acceleration.

Research limitations/implications

Because the aerodynamic force will reduce drastically as the orbital altitude increases, the formation keeping control strategy for small satellites presented in this paper should be limited to the scenarios when satellites are in LEO.

Practical implications

The formation keeping control method in this paper can be applied to solve satellite formation keeping problem for small satellites in LEO.

Originality/value

This paper proposes a Lyapunov control strategy for satellite formation keeping considering both lift and drag forces, and simulation results show better performance with high accuracy under J2 perturbation.

Details

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

Keywords

Article
Publication date: 1 February 1986

Thomas J.R. Hughes and Farzin Shakib

A simple modification of J2‐flow theory is made which enables it to approximately represent the reduced stiffness and increased plastic flow of corner‐theory response to…

Abstract

A simple modification of J2‐flow theory is made which enables it to approximately represent the reduced stiffness and increased plastic flow of corner‐theory response to non‐proportional loading. The key idea involves making the plastic modulus a function of the loading direction. A concise radial‐return type numerical algorithm is presented for the constitutive integration.

Details

Engineering Computations, vol. 3 no. 2
Type: Research Article
ISSN: 0264-4401

Article
Publication date: 11 September 2009

Jianlong Yuan, Zhenhua Gao and Xiang‐Ming Wang

The purpose of this paper is to evaluate the effect of different amounts of sodium hydroxide (NaOH) introduced during the resin synthesis on the properties of…

Abstract

Purpose

The purpose of this paper is to evaluate the effect of different amounts of sodium hydroxide (NaOH) introduced during the resin synthesis on the properties of bark‐phenol‐formaldehyde (BPF) adhesives aims at achieving a balance between storage life and other properties of BPF adhesives.

Design/methodology/approach

Based on the best synthetic technologies for the production of BPF adhesives obtained in a previous study, a new synthetic technology is developed for the production of BPF adhesives that involve a three‐step addition of NaOH using different amounts of NaOH in the third charge. Gel permeation chromatography is used to evaluate properties of the phenol‐formaldehyde (PF) and BPF adhesives.

Findings

The amount of NaOH in the third charge has an important influence on many BPF adhesive properties. The paper determines that the synthetic technology involving three‐step NaOH additions with only water introduced in the third charge of NaOH produces a BPF adhesive with the longest storage life and best bonding strength.

Research limitations/implications

BPF adhesives are very complex systems with many unknown variables.

Practical implications

The improved storage life of the BPF adhesive prepared with the new synthetic technology is comparable to that of a commercial PF adhesive, which indicates that this new technology shows greater potential for commercial applications.

Originality/value

A new synthetic technology is developed to produce a BPF adhesive that is more comparable to commercial PF adhesives than other BPF adhesives in terms of storage life and other resin properties.

Details

Pigment & Resin Technology, vol. 38 no. 5
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 1 August 1998

Xiaohua Bao, Ning‐Cheng Lee, Rajkumar B. Raj, K.P. Rangan and Anu Maria

The rheology of solder paste significantly affects the qualities of stencil printing, tack and slump performance. This paper describes a series of tests performed on…

Abstract

The rheology of solder paste significantly affects the qualities of stencil printing, tack and slump performance. This paper describes a series of tests performed on solder paste to investigate and determine the rheological properties of a group of solder pastes and fluxes, and the correlation of those properties with paste performance prior to reflow. Data indicate that: the incidence of print defects are proportional to the material’s compliant qualities (J1 and J2) and are inversely proportional to the elastic properties (G¢/G¢¢ and recovery) and meta‐rigidity (yield stress); slump resistance is proportional to elastic properties (recovery), solid characteristics (stress [G¢ = G¢¢]), and rigidity (|G*|); and that high elastic properties (recovery), low compliance (J1 and J2), and low solid characteristics (stress [G¢ = G¢¢]) are required in order to achieve high tack value. Good correlation between fluxes and solder pastes were observed for yield stress and recovery only, suggesting that those two properties are primarily dictated by fluxes.

Details

Soldering & Surface Mount Technology, vol. 10 no. 2
Type: Research Article
ISSN: 0954-0911

Keywords

Article
Publication date: 1 November 1949

T. Tonkin

Type: Composite construction, strut braced, high wing mono‐plane.

Abstract

Type: Composite construction, strut braced, high wing mono‐plane.

Details

Aircraft Engineering and Aerospace Technology, vol. 21 no. 11
Type: Research Article
ISSN: 0002-2667

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…

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: 12 October 2012

Guoqiang Zeng, Min Hu and Junling Song

The purpose of this paper is to evaluate the safety of formation flying satellites, and propose a method for practical collision monitoring and collision avoidance manoeuvre.

Abstract

Purpose

The purpose of this paper is to evaluate the safety of formation flying satellites, and propose a method for practical collision monitoring and collision avoidance manoeuvre.

Design/methodology/approach

A general formation description method based on relative orbital elements is proposed, and a collision probability calculation model is established. The formula for the minimum relative distance in the crosstrack plane is derived, and the influence of J2 perturbation on formation safety is analyzed. Subsequently, the optimal collision avoidance manoeuvre problem is solved using the framework of linear programming algorithms.

Findings

The relative orbital elements are illustrative of formation description and are easy to use for perturbation analysis. The relative initial phase angle between the in‐plane and cross‐track plane motions has considerable effect on the formation safety. Simulations confirm the flexibility and effectiveness of the linear programming‐based collision avoidance manoeuvre method.

Practical implications

The proposed collision probability method can be applied in collision monitoring for the proximity operations of spacecraft. The presented minimum distance calculation formula in the cross‐track plane can be used in safe configuration design. Additionally, the linear programming method is suitable for formation control, in which the initial and terminal states are provided.

Originality/value

The relative orbital elements are used to calculate collision probability and analyze formation safety. The linear programming algorithms are extended for collision avoidance, an approach that is simple, effective, and more suitable for on‐board implementation.

1 – 10 of 480