Event-triggered neuroadaptive attitude control for spacecraft with fixed-time prescribed performance

2020 ◽  
Author(s):  
Qi Li ◽  
Xueping Wang ◽  
Qiuxiong Gou ◽  
Zhiqi Niu ◽  
Li Ding ◽  
...  
Keyword(s):  
Attitude Control ◽  
Fixed Time ◽  
Prescribed Performance ◽  
Event Triggered

Fault-tolerant attitude control for flexible spacecraft subject to input and state constraint

2020 ◽  
Vol 42 (14) ◽  
pp. 2660-2674
Author(s):  
Mehdi Golestani ◽  
Seyed Majid Esmaeilzadeh ◽  
Bing Xiao
Keyword(s):  
Attitude Control ◽  
Actuator Saturation ◽  
Fault Tolerant ◽  
Sliding Mode ◽  
Fixed Time ◽  
State Constraint ◽  
Flexible Spacecraft ◽  
Convergence Time ◽  
Prescribed Performance ◽  
High Attitude

This paper considers the problem of fault-tolerant attitude control for a flexible spacecraft subject to input and state constraint. Particularly, a new sliding mode-based attitude control with fixed-time convergent for the flexible spacecraft is developed in which the convergence rate of the system state is improved both far from and at close range of the origin. In contrast to the existing complicated prescribed performance controls (PPC), the proposed PPC possesses a much simpler structure due to the use of a novel constraint concept without employing error transformation. It also introduces a modified prescribed performance function (MPPF) to explicitly determine the settling time. It is rigorously proved that the attitude variable is kept within the predefined constraint boundaries even when the actuator saturation is taken into account. Moreover, the proposed controller is inherently continuous and the chattering is effectively reduced. An adaptive mechanism is developed in which no prior knowledge of the lumped uncertainties is required. Finally, numerical simulations are presented to demonstrate that the proposed controller is able to successfully accomplish attitude control with high attitude pointing accuracy and stability. More specifically, it provides faster convergence (improvement percentage of convergence time (IP_CT) is about 18%) and more accurate control (improvement percentages of MRPs (IP_MRPs) and angular velocity (IP_AV) are about 60% and 80%, respectively) under healthy actuators. Values of IP_CT, IP_CT, and IP_AV are 50%, 99.9% and 99.9% under faulty actuators, respectively.

Event-triggered integral sliding mode fixed time control for trajectory tracking of autonomous underwater vehicle

2021 ◽  
pp. 014233122199438
Author(s):  
Bo Su ◽  
Hongbin Wang ◽  
Ning Li
Keyword(s):  
Trajectory Tracking ◽  
Control Strategy ◽  
Autonomous Underwater Vehicle ◽  
Sliding Mode ◽  
Fixed Time ◽  
Underwater Vehicle ◽  
Reference Trajectory ◽  
Integral Sliding Mode ◽  
Time Control ◽  
Event Triggered

In this paper, an event-triggered integral sliding mode fixed-time control method for trajectory tracking problem of autonomous underwater vehicle (AUV) with disturbance is investigated. Initially, the global fixed time stability is ensured with conventional periodic sampling method for reference trajectory tracking. By introducing fixed time integral sliding mode manifold, fixed time control strategy is expressed for the AUV, which can effectively eliminate the singularity. Correspondingly, in order to reduce the damage caused by chattering phenomenon, an adaptive fixed-time method is proposed based on the designed continuous integral terminal sliding mode (ITSM) to ensure that the trajectory tracking for AUV is achieved in fixed-time with external disturbance. In order to reduce resource consumption in the process of transmission network, the event-triggered sliding mode control strategy is designed which condition is triggered by an event. Also, Zeno behavior is avoided by proof of theoretical. It is shown that the upper bounds of settling time are only dependent on the parameters of controller. Theoretical analysis and simulation experiment results show that the presented methods can realize the control object.

Sign in / Sign up

Export Citation Format

Share Document