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Article
Publication date: 15 May 2009

Wu Xiande, Li Hui and Sun Zhaowei

The micro‐satellite clusters have been discussed for several years, however, there is not a common framework about its software, and various researches distributed at…

Abstract

Purpose

The micro‐satellite clusters have been discussed for several years, however, there is not a common framework about its software, and various researches distributed at different domains. In order to conduct the future work well, the purpose of this paper is to systematically describe micro‐satellite clusters' characteristics, clusters software model, and present a distributed testbed to shorten test process, and minimize the development cost.

Design/methodology/approach

The cluster characteristics and model is summarized through analyzing the past satellite cluster programs. Then the ground test system is designed to shorten micro‐satellite's development period, improve its reliability.

Findings

The clusters' characteristics are discussed, such as coverage, scalability, fault tolerance, low cost, etc. The clusters' data flow and on‐board software architecture are presented according to properties of clusters. Finally, the distributed testbed that focuses on future on‐board software and hardware technologies that aim to rapid design, build, integration, test, deployment, and operation of the future micro‐satellite is designed.

Originality/value

The presentation of software architecture of cluster member can improve the micro‐satellite's development, and the distributed testbed can improve the ground test efficiency, especially, when the micro‐satellite quantity is big.

Details

Aircraft Engineering and Aerospace Technology, vol. 81 no. 3
Type: Research Article
ISSN: 0002-2667

Keywords

Article
Publication date: 5 July 2011

Takaya Inamori, Nobutada Sako and Shinichi Nakasuka

This paper aims to present an attitude determination and control system for a nano‐astrometry satellite which requires precise angular rate control. Focus of the research…

Abstract

Purpose

This paper aims to present an attitude determination and control system for a nano‐astrometry satellite which requires precise angular rate control. Focus of the research is methods to achieve the requirement.

Design/methodology/approach

In order to obtain astrometry data, the satellite attitude should be controlled to an accuracy of 0.05°. Furthermore, attitude spin rate must be controlled to an accuracy of 4×10−7 rad/s during observation. In this paper the following unique ideas to achieve these requirements are introduced: magnetic disturbance compensation and rate estimation using star blurred images.

Findings

This paper presents the feasibility of a high accurate attitude control system in nano‐ and micro‐satellite missions.

Practical implications

This paper presents a possibility of the application of nano‐satellites to remote‐sensing and astronomy mission, which requires accurate attitude control.

Originality/value

Originalities of the paper are the methods to achieve the high accurate attitude control: magnetic disturbance compensation and angular rate estimation using star images.

Details

Aircraft Engineering and Aerospace Technology, vol. 83 no. 4
Type: Research Article
ISSN: 0002-2667

Keywords

Article
Publication date: 16 March 2012

Jianmin Su and Yunfeng Dong

Fractionated satellite clusters need coming together and avoiding crashing with limited random initial relative motion conditions. It is not necessary to keep the…

Abstract

Purpose

Fractionated satellite clusters need coming together and avoiding crashing with limited random initial relative motion conditions. It is not necessary to keep the invariable configuration. The purpose of this paper is to put forward a control law which simulates organism swarm motion.

Design/methodology/approach

The motion of satellites follows three rules: coming together, velocity homology and avoiding crash. According to the rules, three control forces should be applied to satellite individuals. The final control force is the sum of three control forces. Electromagnetic dipole strengths calculation is formulated as nonlinear optimization problem. Considering control strengths have to be got in real time, iterative steps of optimization algorithm are fixed.

Findings

A control law which simulates organism swarm motion is put forward. The simulation shows the organism swarm motion simulation control law can keep fractionated satellite cluster coming together and avoiding crash. When iterative steps of optimization algorithm is fixed, the error of solve nonlinear equations is acceptable.

Originality/value

The control law is robust and easy to realize. When electromagnetic satellite cluster need not keep fixed configuration, it is a choice of control law of relative motion.

Details

Aircraft Engineering and Aerospace Technology, vol. 84 no. 2
Type: Research Article
ISSN: 0002-2667

Keywords

Article
Publication date: 23 January 2009

Zhai kun and Yang Di

The purpose of this paper is to provide a feasible method to solve the zenith pass problem that can occur when the inter‐satellite linkage antenna of the user satellite is…

Abstract

Purpose

The purpose of this paper is to provide a feasible method to solve the zenith pass problem that can occur when the inter‐satellite linkage antenna of the user satellite is tracing TDRS. The antenna uses the elevation‐over‐azimuth architecture.

Design/methodology/approach

The movement laws of the inter‐satellite linkage can be obtained based on the orbit predictions of the user satellite and TDRS. According to the movement laws, the zenith pass moments and blindness zones are found. The trajectory preprocessor is provided to design a command trajectory for driving the axis of the tilting mechanism.

Findings

In the worst situation, the blindness zone can appear once every half day. Three special orbit altitude values are obtained. When the user satellite picks one of them as its orbit altitude, the blindness zone may be avoided forever. The zenith pass tracing strategies based on the mechanical tilting method have been designed.

Research limitations/implications

This method obtains the stable tracking during the zenith pass course by changing the hardware structure of the antenna. It is too expensive and can influence the pointing precision of the antenna.

Practical implications

The research can help the engineers analyze and solve the zenith pass problem of the antenna.

Originality/value

This paper studies the zenith pass problem that can occur when the inter‐satellite linkage antenna of the user satellite is tracing TDRS and provides a solving method.

Details

Aircraft Engineering and Aerospace Technology, vol. 81 no. 2
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: 19 April 2022

Jie Zhang, Weihua Xie, Yakun Wang, Jiang Zhou and Jiacong Yin

This paper aims to fast predict vibration responses of specific locations in the satellite subject to acoustic environment. It proposes a set of vibro-acoustic simulation…

Abstract

Purpose

This paper aims to fast predict vibration responses of specific locations in the satellite subject to acoustic environment. It proposes a set of vibro-acoustic simulation methods of satellite components to represent their conditions in the whole satellite during the ground tests or launching. This study aims to use vibro-acoustic models of satellite components to replace that of hard modeling and time-consuming whole satellite when only local responses are concerned.

Design/methodology/approach

This paper adopted experimental and numerical studies, with the latter based on the finite element (FE), statistical energy analysis (SEA) and FE-SEA hybrid theories. The vibro-acoustic model of the whole satellite was built and verified by experimental data. Based on the whole satellite model and experimental results, the fast vibro-acoustic simulation methods of all kinds of typical satellite components were discussed.

Findings

This paper shows that the models about satellite components not only show high consistency but also reduce 61.6% to 99.8% times compared with the whole satellite model. The recommended fast simulation methods for all kinds of typical satellite components were given in comprehensive consideration of the model accuracy, time required and response accessibility.

Originality/value

This paper fulfils an identified need to perform fast vibro-acoustic prediction of the local positions in satellites.

Details

Aircraft Engineering and Aerospace Technology, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1748-8842

Keywords

Article
Publication date: 11 August 2021

Wienand Kölle, Matthias Buchholz and Oliver Musshoff

Satellite-based weather index insurance has recently been considered in order to reduce the high basis risk of station-based weather index insurance. However, the use of…

Abstract

Purpose

Satellite-based weather index insurance has recently been considered in order to reduce the high basis risk of station-based weather index insurance. However, the use of satellite data with a relatively low spatial resolution has not yet made it possible to determine the satellite indices free of disturbing landscape elements such as mountains, forests and lakes.

Design/methodology/approach

In this context, the Normalized Difference Vegetation Index (NDVI) was used based on both Moderate Resolution Imaging Spectroradiometer (MODIS) (250 × 250 m) and high-resolution Landsat 5/8 (30 × 30 m) images to investigate the effect of a higher spatial resolution of satellite-based weather index contracts for hedging winter wheat yields. For three farms in north-east Germany, insurance contracts both at field and farm level were designed.

Findings

The results indicate that with an increasing spatial resolution of satellite data, the basis risk of satellite-based weather index insurance contracts can be reduced. However, the results also show that the design of NDVI-based insurance contracts at farm level also reduces the basis risk compared to field level. The study shows that higher-resolution satellite data are advantageous, whereas satellite indices at field level do not reduce the basis risk.

Originality/value

To the best of the author’s knowledge, the effect of increasing spatial resolution of satellite images for satellite-based weather index insurance is investigated for the first time at the field level compared to the farm level.

Details

Agricultural Finance Review, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0002-1466

Keywords

Article
Publication date: 16 July 2021

Junfu Chen, Xiaodong Zhao and Dechang Pi

The purpose of this paper is to ensure the stable operation of satellites in orbit and to assist ground personnel in continuously monitoring the satellite telemetry data…

Abstract

Purpose

The purpose of this paper is to ensure the stable operation of satellites in orbit and to assist ground personnel in continuously monitoring the satellite telemetry data and finding anomalies in advance, which can improve the reliability of satellite operation and prevent catastrophic losses.

Design/methodology/approach

This paper proposes a deep auto-encoder (DAE) satellite anomaly advance warning framework for satellite telemetry data. Firstly, this study performs grey correlation analysis, extracts important feature attributes to construct feature vectors and builds the variational auto-encoder with bidirectional long short-term memory generative adversarial network discriminator (VAE/BLGAN). Then, the Mahalanobis distance is used to measure the reconstruction score of input and output. According to the periodic characteristic of satellite operation, a dynamic threshold method based on periodic time window is proposed. Satellite health monitoring and advance warning are achieved using reconstruction scores and dynamic thresholds.

Findings

Experiment results indicate DAE methods can probe that satellite telemetry data appear abnormal, trigger a warning before the anomaly occurring and thus allow enough time for troubleshooting. This paper further verifies that the proposed VAE/BLGAN model has stronger data learning ability than other two auto-encoder models and is sensitive to satellite monitoring data.

Originality/value

This paper provides a DAE framework to apply in the field of satellite health monitoring and anomaly advance warning. To the best of the authors’ knowledge, this is the first paper to combine DAE methods with satellite anomaly detection, which can promote the application of artificial intelligence in spacecraft health monitoring.

Details

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

Keywords

Article
Publication date: 14 June 2021

Ruirui Shao, Zhigeng Fang, Liangyan Tao, Su Gao and Weiqing You

During the service period of communication satellite systems, their performance is often degraded due to the depletion mechanism. In this paper, the grey system theory is…

Abstract

Purpose

During the service period of communication satellite systems, their performance is often degraded due to the depletion mechanism. In this paper, the grey system theory is applied to the multi-state system effectiveness evaluation and the grey Lz-transformation ADC (availability, dependability and capability) effectiveness evaluation model is constructed to address the characteristics of the communication satellite system such as different constituent subsystems, numerous states and the inaccuracy and insufficiency of data.

Design/methodology/approach

The model is based on the ADC effectiveness evaluation method, combined with the Lz transformation and uses the definite weighted function of the three-parameter interval grey number as a bridge to incorporate the possibility of system performance being greater than the task demand into the effectiveness solution algorithm. At the same time, using MATLAB (Matrix laboratory) to solve each state probability, the same performance level in the Lz transform is combined. Then, the system effectiveness is obtained by Python.

Findings

The results show that the G-Lz-ADC model constructed in this paper can accurately evaluate the effectiveness of static/dynamic systems and certain/uncertain system and also has better applicability in evaluating the effectiveness of the multi-state complex system.

Practical implications

The G-Lz-ADC effectiveness evaluation model constructed in this paper can effectively reduce the complexity of traditional effectiveness evaluation models by combining the same performance levels in the Lz-transform and solving the effectiveness of the system with the help of computer programming, providing a new method for the effectiveness evaluation of the complex MSS. At the same time, the weaknesses of the system can be identified, providing a theoretical basis for improving the system’s effectiveness.

Originality/value

The possibility solution method based on the definite weighted function comparing the two three-parameter interval grey numbers is constructed, which compensates for the traditional calculation of the probability based on numerical values and subjective preferences of decision-makers. Meanwhile, the effectiveness evaluation model integrates the basic theories of three-parameter interval grey number and its definite weighted function, Grey−Markov, grey universal generating function (GUGF), grey multi-state system (GMSS), etc., which is an innovative method to solve the effectiveness of a multi-state instantaneous communication satellite system.

Details

Grey Systems: Theory and Application, vol. 12 no. 2
Type: Research Article
ISSN: 2043-9377

Keywords

Article
Publication date: 15 June 2021

Mohd Badrul Salleh, Nurulasikin Mohd Suhadis and Renuganth Varatharajoo

This paper aims to investigate the attitude control pointing improvement for a small satellite with control moment gyroscopes (CMGs) using the active force control (AFC) method.

Abstract

Purpose

This paper aims to investigate the attitude control pointing improvement for a small satellite with control moment gyroscopes (CMGs) using the active force control (AFC) method.

Design/methodology/approach

The AFC method is developed with its governing equations and integrated into the conventional proportional-derivative (PD) controller of a closed-loop satellite attitude control system. Two numerical simulations of an identical attitude control mission namely the PD controller and the PD+AFC controller were carried out using the MATLAB®-SimulinkTM software and their attitude control performances were demonstrated accordingly.

Findings

Having the PD+AFC controller, the attitude maneuver can be completed within the desired slew rate, which is about 2.14 degree/s and the attitude pointing accuracies for the roll, pitch and yaw angles have improved significantly by more than 85% in comparison with the PD controller alone. Moreover, the implementation of the AFC into the conventional PD controller does not cause significant difference on the physical structure of the four single gimbal CMGs (4-SGCMGs).

Practical implications

To achieve a precise attitude pointing mission, the AFC method can be applied directly to the existing conventional PD attitude control system of a CMG-based satellite. In this case, the AFC is indeed the backbone for the satellite attitude performance improvement.

Originality/value

The present study demonstrates that the attitude pointing of a small satellite with CMGs is improved through the implementation of the AFC scheme into the PD controller.

Details

Aircraft Engineering and Aerospace Technology, vol. 93 no. 7
Type: Research Article
ISSN: 1748-8842

Keywords

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