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1 – 3 of 3Chengxi 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 resources…
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
Keywords
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
Keywords
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