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Article
Publication date: 19 March 2021

Chengxi Zhang, Jin Wu, Yulong Huang, Yu Jiang, Ming-zhe Dai and Mingjiang Wang

Recent spacecraft attitude control systems tend to use wireless communication for cost-saving and distributed mission purposes while encountering limited communication…

Abstract

Purpose

Recent spacecraft attitude control systems tend to use wireless communication for cost-saving and distributed mission purposes while encountering limited communication resources and data exposure issues. This paper aims to study the attitude control problem with low communication frequency under the sampled-data.

Design/methodology/approach

The authors propose constructive control system structures based on quantization and event-triggered methods for intra-spacecraft and multi-spacecraft systems, and they also provide potential solutions to shield the control system's data security. The proposed control architectures can effectively save communication resources for both intra-spacecraft and multi-spacecraft systems.

Findings

The proposed control architectures no longer require sensors with trigger-ing mechanism and can achieve distributed control schemes. This paper also provides proposals of employing the public key encryption to secure the data in control-loop, which is transmitted by the event-triggered control mechanism.

Practical implications

Spacecraft attempts to use wireless communication, yet the attitude control system does not follow up promptly to accommodate these variations. Compared with existing approaches, the proposed control structures can save communication resources of control-loop in multi-sections effectively, and systematically, by rationally configuring the location of quantization and event-triggered mechanisms.

Originality/value

This paper presents several new control schemes and a necessary condition for the employment of encryption algorithms for control systems based on event-based communication.

Details

Aircraft Engineering and Aerospace Technology, vol. 93 no. 2
Type: Research Article
ISSN: 1748-8842

Keywords

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Article
Publication date: 8 April 2021

Chengxi Zhang, Jin Wu, Ran Sun, Mingjiang Wang and Dechao Ran

The purpose of this paper is to study the general actuator modeling in spacecraft attitude control systems.

Abstract

Purpose

The purpose of this paper is to study the general actuator modeling in spacecraft attitude control systems.

Design/methodology/approach

The proposed module in this paper provides various non-ideal factors such as the second-order dynamic time response, time-delay, bias torques, dead-zones and saturation. The actuator module can make the simulation as close to the practical situation as possible.

Findings

This paper presents a practical integrated module for the simulation of attitude control algorithms. Based on theoretical modeling, we give simulation modules and numerical examples. The proposed model can be directly used in spacecraft control simulation. Instead of considering only a few of them, it makes the simulation more convincing. Though it may not be perfect, it is better than totally ignoring the actuator dynamics.

Originality/value

The authors provide an integrated actuator model for spacecraft attitude control simulation, considering as many nonlinear factors as possible once time.

Details

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

Keywords

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Article
Publication date: 3 February 2020

Changhua Liu, Jide Qian, Zuocai Wang and Jin Wu

For fixed-wing micro air vehicles, the attitude determination is usually produced by the horizon/Global Navigation Satellite System (GNSS) in which the GNSS provides yaw…

Abstract

Purpose

For fixed-wing micro air vehicles, the attitude determination is usually produced by the horizon/Global Navigation Satellite System (GNSS) in which the GNSS provides yaw estimates, while roll and pitch are computed using horizon sensors. However, the attitude determination has been independently obtained from the two sensors, which will result in insufficient usage of data. Also, when implementing attitude determination algorithms on embedded platforms, the computational resources are highly restricted. This paper aims to propose a computationally efficient linear Kalman filter to solve the problem.

Design/methodology/approach

The observation model is in the form of a least-square optimization composed by GNSS and horizontal measurements. Analytical quaternion solution along with its covariance is derived to significantly speed up on-chip computation.

Findings

The reconstructed attitude from Horizon/GNSS is integrated with quaternion kinematic equation from gyroscopic data that builds up a fast linear Kalman filter. The proposed filter does not involve coupling effects presented in existing works and will be more robust encountering bad GNSS measurements.

Originality/value

Electronic systems are designed on a real-world fixed-wing plane. Experiments are conducted on this platform that show comparisons on the accuracy and computation execution time of the proposed method and existing representatives. The results indicate that the proposed algorithm is accurate and much faster computation speed in studied scenarios.

Details

Sensor Review, vol. 40 no. 2
Type: Research Article
ISSN: 0260-2288

Keywords

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Article
Publication date: 7 October 2021

Chengxi Zhang, Peng Dong, Henry Leung, Jin Wu and Kai Shen

This paper aims to investigate the attitude regulation for spacecraft in the presence of time-varying inertia uncertainty and exogenous disturbances.

Abstract

Purpose

This paper aims to investigate the attitude regulation for spacecraft in the presence of time-varying inertia uncertainty and exogenous disturbances.

Design/methodology/approach

The high gain approaches are typically used in existing researches for theoretical advantages, bringing better performance but sensitive to parameter selection, making the controller conservative. A reset-control policy is presented to achieve the spacecraft attitude control with easy control parameter tuning.

Findings

The reset-control policy guarantees satisfying control performance despite using performance tuning function and saturation function besides reducing the conservativeness of the controller, thus reducing the effort in tuning control parameters.

Originality/value

Notably, the adaptive function owns a reset mechanism, which is reset to a preset condition when the controlled variable crosses zero. The mathematical analysis also shows the system trajectory can converge to a set centered at the origin.

Details

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

Keywords

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Article
Publication date: 26 July 2021

Jin Wu, Ming Liu, Chengxi Zhang, Yulong Huang and Zebo Zhou

Autonomous orbit determination using geomagnetic measurements is an important backup technique for safe spacecraft navigation with a mere magnetometer. The geomagnetic…

Abstract

Purpose

Autonomous orbit determination using geomagnetic measurements is an important backup technique for safe spacecraft navigation with a mere magnetometer. The geomagnetic model is used for the state estimation of orbit elements, but this model is highly nonlinear. Therefore, many efforts have been paid to developing nonlinear filters based on extended Kalman filter (EKF) and unscented Kalman filter (UKF). This paper aims to analyze whether to use UKF or EKF in solving the geomagnetic orbit determination problem and try to give a general conclusion.

Design/methodology/approach

This paper revisits the problem and from both the theoretical and engineering results, the authors show that the EKF and UKF show identical estimation performances in the presence of nonlinearity in the geomagnetic model.

Findings

While EKF consumes less computational time, the UKF is computationally inefficient but owns better accuracy for most nonlinear models. It is also noted that some other navigation techniques are also very similar with the geomagnetic orbit determination.

Practical implications

The intrinsic reason of such equivalence is because of the orthogonality of the spherical harmonics which has not been discovered in previous studies. Thus, the applicability of the presented findings are not limited only to the major problem in this paper but can be extended to all those schemes with spherical harmonic models.

Originality/value

The results of this paper provide a fact that there is no need to choose UKF as a preferred candidate in orbit determination. As UKF achieves almost the same accuracy as that of EKF, its loss in computational efficiency will be a significant obstacle in real-time implementation.

Details

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

Keywords

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Article
Publication date: 5 June 2020

Chengxi Zhang, Jin Wu, Ming-Zhe Dai, Bo Li and Mingjiang Wang

The purpose of this paper is to investigate the attitude cooperation control of multi-spacecraft with in-continuous communication.

Abstract

Purpose

The purpose of this paper is to investigate the attitude cooperation control of multi-spacecraft with in-continuous communication.

Design/methodology/approach

A decentralized state-irrelevant event-triggered control policy is proposed to reduce control updating frequency and further achieve in-continuous communication by introducing a self-triggered mechanism.

Findings

Each spacecraft transmits data independently, without the requirement for the whole system to communicate simultaneously. The local predictions and self-triggered mechanism avoid continuous monitoring of the triggering condition.

Research limitations/implications

This investigation is suitable for small Euler angle conditions.

Practical implications

The control policy based on event-triggered communication can provide potential solutions for saving communication resources.

Originality/value

This investigation uses event- and self-triggered policy to achieve in-communication for the multi-spacecraft system.

Details

Aircraft Engineering and Aerospace Technology, vol. 92 no. 7
Type: Research Article
ISSN: 1748-8842

Keywords

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Article
Publication date: 20 September 2021

Yu Lu, Pengpeng Ye, Ming-Zhe Dai, Jin Wu and Chengxi Zhang

This paper aims to address the spacecraft attitude regulation problem in the presence of extrinsic disturbances and actuator faults.

Abstract

Purpose

This paper aims to address the spacecraft attitude regulation problem in the presence of extrinsic disturbances and actuator faults.

Design/methodology/approach

Based on adaptive backstepping design technique, a new concise adaptive dual-mode control scheme is proposed, which can either use the fault information detected by fault diagnosis mechanisms or switch to the fault-unknown mode when the fault diagnosis information is non-existent for control signal generation. These two modes share an adaptive mechanism that reduces the complexity of the algorithm.

Findings

The new fault-tolerant attitude control algorithm can accommodate both modes with and without fault diagnosis mechanisms.

Originality/value

The proposed algorithm in this paper can be applied to both cases when the attitude control system is equipped with or without fault diagnosis capability. This also enhances the robustness of attitude control algorithm. This study performs numerical simulations and verifies that the algorithm could effectively adapt to both modes.

Details

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

Keywords

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Article
Publication date: 17 August 2021

Chengxi Zhang, Hui-Jie Sun, Jin Wu, Zhongyang Fei, Yu Jiang and Guanhua Zhang

This paper aims to study the attitude control problem with mutating orbital rate and actuator fading.

Abstract

Purpose

This paper aims to study the attitude control problem with mutating orbital rate and actuator fading.

Design/methodology/approach

To avoid malicious physical attacks and hide itself, the spacecraft may irregularly switch its orbit altitude within a specific range, which will bring about variations in orbital rate, thereby causing mutations in the attitude dynamics model. The actuator faults will also cause changes in system dynamics. Both factors affect the control performance. First, this paper determines the potential switching orbits. Then under different conditions, design controllers that can accommodate actuator faults according to the statistical law of actuator fading.

Findings

This paper, to the best of the authors’ knowledge, for the first time, introduces the Markovian jump framework to model the possible unexpected mutating of orbital rate and actuator fading of spacecraft and then designs a novel control policy to solve the attitude control problem.

Practical implications

This paper also provides the algorithm design processes in detail. A comparative numerical simulation is given to verify the effectiveness of the proposed algorithm.

Originality/value

This is an early solution for spacecraft attitude control with dynamics model mutations.

Details

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

Keywords

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Article
Publication date: 5 May 2020

Jin Wu, Henry J. Liu, Michael C.P. Sing, Richard Humphrey and Jianfeng Zhao

This paper investigates the policy changes made towards infrastructure public–private partnerships (PPPs). The purpose of this study is to empirically identify the policy…

Abstract

Purpose

This paper investigates the policy changes made towards infrastructure public–private partnerships (PPPs). The purpose of this study is to empirically identify the policy risks associated with the development of PPPs and to assess their impacts on the projects.

Design/methodology/approach

A case study of the policy changes that have been implemented for PPPs in China over the past seven years has been undertaken and is presented in this study. The causal loop diagrams are applied to assess and illustrate the potential impacts of the risks as a result of such changes on PPPs.

Findings

A sequence of the policy risks, which relate to PPP risk allocation, contract management and implementation, payment and abatement mechanisms and financing, has been identified. It is also found that the identified risks will generate significant but negative impacts on PPPs, leading to an ineffective project delivery, low revenue, poor service quality and even contract breach.

Practical implications

This research provides the private-sector entities that will embark on PPPs with an insight into managing and controlling policy risks over the project's lifecycle.

Originality/value

PPPs have been critical for infrastructure development worldwide. Nevertheless, they have been a controversy, as many of them were subjected to poor outputs. Consequently, a variety of political mechanisms has been implemented to enhance the governance for PPPs. Policy can bring not only benefits but also risks and, however, policy risks of PPPs with a particular assessment for their potential impacts have received limited attention. Therefore, the study presented in this paper will contribute to the identification and assessment of policy risks within the context of PPPs.

Details

Engineering, Construction and Architectural Management, vol. 27 no. 9
Type: Research Article
ISSN: 0969-9988

Keywords

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Article
Publication date: 28 November 2018

Man Chen, Yong Zhong, Zhendong Li and Jin Wu

This paper aims to investigate a novel shape from focus (SFF) algorithm based on maximum correntropy Kalman filtering (SFF-MCKF) for solving the problem that traditional…

Abstract

Purpose

This paper aims to investigate a novel shape from focus (SFF) algorithm based on maximum correntropy Kalman filtering (SFF-MCKF) for solving the problem that traditional SFF methods are weak in de-noising and spatial continuity.

Design/methodology/approach

To be specific, it was first assumed that the predicted depth of next pixel is equal to the depth of the current pixel according to spatial continuity. Besides, the observing data are derived from the estimation of traditional SFF and the corresponding covariance of noise is adaptively calculated by the entropy along the optical axis. Finally, to enhance robustness, we systematically conduct MCKF iteratively in four transfer directions that are 0°, 90°, 45° and −45°, respectively.

Findings

The experimental results indicate that the robustness of SFF-MCKF facing noises as well as the spatial continuity is better than that of the existing representative ones.

Research limitations/implications

As the proposed method is aimed at precision objects, high demand is for experimental device. Unstable device unregister the source images, which is unfavorable for observing data.

Originality/value

SFF-MCKF can be applied to many precision object measurements without significant drifts, such as the surface reconstruction of metal objects and electronic components. Besides, the computation cost is low, and SFF-MCKF has a wide range of real-time industrial applications.

Details

Sensor Review, vol. 39 no. 3
Type: Research Article
ISSN: 0260-2288

Keywords

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