IEEE/CAA Journal of Automatica Sinica

Abstract:
The economic dispatch problem (EDP) of microgrids operating in both grid-connected and isolated modes within an energy internet framework is addressed in this paper. The multi-agent leader-following consensus algorithm is employed to address the EDP of microgrids in grid-connected mode, while the push-pull algorithm with a fixed step size is introduced for the isolated mode. The proposed algorithm of isolated mode is proven to converge to the optimum when the interaction digraph of microgrids is strongly connected. A unified algorithmic framework is proposed to handle the two modes of operation of microgrids simultaneously, enabling our algorithm to achieve optimal power allocation and maintain the balance between power supply and demand in any mode and any mode switching. Due to the push-pull structure of the algorithm and the use of fixed step size, the proposed algorithm can better handle the case of unbalanced graphs, and the convergence speed is improved. It is documented that when the transmission topology is strongly connected and there is bi-directional communication between the energy router and its neighbors, the proposed algorithm in composite mode achieves economic dispatch even with arbitrary mode switching. Finally, we demonstrate the effectiveness and superiority of our algorithm through numerical simulations.

Adaptive Control of a Flexible Manipulator With Unknown Hysteresis and Intermittent Actuator Faults

Shouyan Chen, Weitian He, Zhijia Zhao, Yun Feng, Zhijie Liu, Keum-Shik Hong

, Available online

[Abstract](13) [FullText HTML] (0) [PDF 3912KB](5)

Abstract:
In this study, we consider a single-link flexible manipulator in the presence of an unknown Bouc-Wen type of hysteresis and intermittent actuator faults. First, an inverse hysteresis dynamics model is introduced, and then the control input is divided into an expected input and an error compensator. Second, a novel adaptive neural network-based control scheme is proposed to cancel the unknown input hysteresis. Subsequently, by modifying the adaptive laws and local control laws, a fault-tolerant control strategy is applied to address uncertain intermittent actuator faults in a flexible manipulator system. Through the direct Lyapunov theory, the proposed scheme allows the state errors to asymptotically converge to a specified interval. Finally, the effectiveness of the proposed scheme is verified through numerical simulations and experiments.

Distributed Observer for Full-Measured Nonlinear Systems Based on Knowledge of FMCF

Haotian Xu, Shuai Liu, Yueyang Li, Ke Li

, Available online , doi: 10.1109/JAS.2024.124467

[Abstract](45) [FullText HTML] (0) [PDF 2819KB](23)

Abstract:
Driven by practical applications, the achievement of distributed observers for nonlinear systems has emerged as a crucial advancement in recent years. However, existing theoretical advancements face certain limitations: They either fail to address more complex nonlinear phenomena, rely on hard-to-verify assumptions, or encounter difficulties in solving system parameters. Consequently, this paper aims to address these challenges by investigating distributed observers for nonlinear systems through the full-measured canonical form (FMCF), which is inspired by full-measured system (FMS) theory. To begin with, this study addresses the fact that the FMCF can only be obtained through the observable canonical form (OCF) in existing FMS theories. The paper demonstrates that a class of nonlinear systems can directly obtain FMCF through state space equations, independent of OCF. Also, a general method for solving FMCF in such systems is provided. Furthermore, based on the FMCF, A distributed observer is developed for nonlinear systems under two scenarios: Lipschitz conditions and open-loop bounded conditions. The paper establishes their asymptotic omniscience and demonstrates that the designed distributed observer in this study has fewer design parameters and is more convenient to construct than existing approaches. Finally, the effectiveness of the proposed methods is validated through simulation results on Van der Pol oscillators and microgrid systems.

Stability and Stabilization of Sampled-Data Based LFC for Power Systems: A Data-Driven Method

Yu-Long Fan, Chuan-Ke Zhang, Yong He

, Available online

[Abstract](12) [FullText HTML] (0) [PDF 494KB](4)

Abstract:

Multi-Phase Degradation Modeling Based on Uncertain Random Process for Remaining Useful Life Prediction Under Triple Uncertainties

Xuerui Cao, Kaixiang Peng, Ruihua Jiao

, Available online

[Abstract](6) [FullText HTML] (0) [PDF 3338KB](2)

Abstract:
Due to abrupt changes in the intrinsic degradation mechanism or shock from external environmental pressure, degradations of some equipment are characterized by multi-phase and jumps. Meanwhile, equipment is subject to inherent fluctuations, limited data and imperfect measurements resulting in aleatory, epistemic and measurement uncertainties of the degradation process. This paper proposes a degradation model and remaining useful life (RUL) prediction method under triple uncertainties for a category of complex equipment with multi-phase degradation and jumps. First, a multi-phase degradation model with random jumps and measurement errors is constructed based on uncertain random processes. Afterward, the analytic expression of RUL prediction considering the heterogeneity is derived by modeling the uncertainty of degradation states at change points under the concept of first hitting time. A stochastic uncertain approach is utilized for the proposed multi-phase degradation model to identify model parameters based on historical data. Furthermore, the implied degradation features are adaptively updated in online stage using similarity-based weighted stochastic uncertain maximum likelihood estimation and Kalman filtering. Finally, the effectiveness of the method is verified by simulation example and practical case.

Hazard-Aware Weighted Advantage Combination for UAV Target Tracking and Obstacle Avoidance

Lele Xu, Jian Liu, Xiaoguang Chang, Xuping Liu, Changyin Sun

, Available online , doi: 10.1109/JAS.2024.124920

[Abstract](20) [FullText HTML] (0) [PDF 4178KB](3)

Abstract:
In recent years, the rapid evolution of unmanned aerial vehicles (UAVs) has brought about transformative changes across various industries. However, addressing fundamental challenges in UAV technology, particularly target tracking and obstacle avoidance, remains crucial for wildlife protection, military industry security, etc. Many existing methods based on reinforcement learning to solve UAV multi-tasks need to be redesigned and retrained, and cannot be quickly and effectively extended to other scenarios. To this end, we propose a novel solution based on a hazard-aware weighted advantage combination for UAV target tracking and obstacle avoidance. First, we independently trained the UAV target tracking and obstacle avoidance using the Dueling Double Deep Q-Network reinforcement learning algorithm. Subsequently, in a multitasking scenario, we introduce the two pre-trained networks. Meanwhile, we design a weight determined by the present risk level encountered by the UAV. This weight is utilized to perform a weighted summation of the advantage values from both networks, eliminating the need for retraining to obtain the final action. We validate our approach through extensive simulation experiments in the robotics simulator known as CoppeliaSim. The results demonstrate that our method outperforms current state-of-the-art techniques, achieving superior performance in both tracking accuracy and avoidance of collisions.

Beyond Performance of Learning Control Subject to Uncertainties and Noise: A Frequency-Domain Approach Applied to Wafer Stages

Fazhi Song, Ning Cui, Shuaiqi Chen, Kai Zhang, Yang Liu, Xinkai Chen, Jiubin Tan

, Available online , doi: 10.1109/JAS.2024.124968

[Abstract](12) [FullText HTML] (0) [PDF 3520KB](5)

Abstract:
The increasingly stringent performance requirement in integrated circuit manufacturing, characterized by smaller feature sizes and higher productivity, necessitates the wafer stage executing a extreme motion with the accuracy in terms of nanometers. This demanding requirement witnesses a widespread application of iterative learning control (ILC), given the repetitive nature of wafer scanning. ILC enables substantial performance improvement by using past measurement data in combination with the system model knowledge. However, challenges arise in cases where the data is contaminated by the stochastic noise, or when the system model exhibits significant uncertainties, constraining the achievable performance. In response to this issue, an extended state observer (ESO) based adaptive ILC approach is proposed in the frequency domain. Despite being model-based, it utilizes only a rough system model and then compensates for the resulting model uncertainties using an ESO, thereby achieving high robustness against uncertainties with minimal modeling effort. Additionally, an adaptive learning law is developed to mitigate the limited performance in the presence of stochastic noise, yielding high convergence accuracy yet without compromising convergence speed. Simulation and experimental comparisons with existing model-based and data-driven inversion-based ILC validate the effectiveness as well as the superiority of the proposed method.

Joint Probabilistic Scheduling and Resource Allocation for Wireless Networked Control Systems

Meng Zheng, Lei Zhang, Wei Liang

, Available online

[Abstract](19) [FullText HTML] (0) [PDF 746KB](4)

Abstract:

Interpretable Data-Driven Learning With Fast Ultrasonic Detection for Battery Health Estimation

Kailong Liu, Yuhang Liu, Qiao Peng, Naxin Cui, Chenghui Zhang

, Available online

[Abstract](10) [FullText HTML] (0) [PDF 2420KB](4)

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Data-Driven Fault-Tolerant Bipartite Consensus Tracking for Multi-Agent Systems With a Non-Autonomous Leader

Yan Zhou, Guanghui Wen, Jialing Zhou, Tao Yang

, Available online

[Abstract](7) [FullText HTML] (0) [PDF 756KB](2)

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The H_∞ Robust Stability and Performance Conditions for Uncertain Robot Manipulators

Geun Il Song, Hae Yeon Park, Jung Hoon Kim

, Available online

[Abstract](6) [FullText HTML] (0) [PDF 957KB](3)

Abstract:

Detection of Perfect Stealthy Attacks on Cyber-Physical Systems Subject to Measurement Quantizations: A Watermark-Based Strategy

Yu-Ang Wang, Zidong Wang, Lei Zou, Bo Shen, Hongli Dong

, Available online

[Abstract](9) [FullText HTML] (0) [PDF 2010KB](4)

Abstract:
In this paper, the attack detection problem is investigated for a class of closed-loop systems subjected to unknown-but-bounded noises in the presence of stealthy attacks. The measurement outputs from the sensors are quantized before transmission. A specific type of perfect stealthy attack, which meets certain rather stringent conditions, is taken into account. Such attacks could be injected by adversaries into both the sensor-to-estimator and controller-to-actuator channels, with the aim of disrupting the normal data flow. For the purpose of defending against these perfect stealthy attacks, a novel scheme based on watermarks is developed. This scheme includes the injection of watermarks (applied to data prior to quantization) and the recovery of data (implemented before the data reaches the estimator). The watermark-based scheme is designed to be both time-varying and hidden from adversaries through incorporating a time-varying and bounded watermark signal. Subsequently, a watermark-based attack detection strategy is proposed which thoroughly considers the characteristics of perfect stealthy attacks, thereby ensuring that an alarm is activated upon the occurrence of such attacks. An example is provided to demonstrate the efficacy of the proposed mechanism for detecting attacks.

Safe Q-Learning for Data-Driven Nonlinear Optimal Control With Asymmetric State Constraints

Mingming Zhao, Ding Wang, Shijie Song, Junfei Qiao

, Available online , doi: 10.1109/JAS.2024.124509

[Abstract](86) [FullText HTML] (0) [PDF 2993KB](38)

Abstract:
This article develops a novel data-driven safe Q-learning method to design the safe optimal controller which can guarantee constrained states of nonlinear systems always stay in the safe region while providing an optimal performance. First, we design an augmented utility function consisting of an adjustable positive definite control obstacle function and a quadratic form of the next state to ensure the safety and optimality. Second, by exploiting a pre-designed admissible policy for initialization, an off-policy stabilizing value iteration Q-learning (SVIQL) algorithm is presented to seek the safe optimal policy by using offline data within the safe region rather than the mathematical model. Third, the monotonicity, safety, and optimality of the SVIQL algorithm are theoretically proven. To obtain the initial admissible policy for SVIQL, an offline VIQL algorithm with zero initialization is constructed and a new admissibility criterion is established for immature iterative policies. Moreover, the critic and action networks with precise approximation ability are established to promote the operation of VIQL and SVIQL algorithms. Finally, three simulation experiments are conducted to demonstrate the virtue and superiority of the developed safe Q-learning method.

Dissecting and Mitigating Semantic Discrepancy in Stable Diffusion for Image-to-Image Translation

Yifan Yuan, Guanqun Yang, James Z. Wang, Hui Zhang, Hongming Shan, Feiyue Wang, Junping Zhang

, Available online , doi: 10.1109/JAS.2024.124800

[Abstract](16) [FullText HTML] (0) [PDF 96202KB](3)

Abstract:
Finding suitable initial noise that retains the original image’s information is crucial for image-to-image (I2I) translation using text-to-image (T2I) diffusion models. A common approach is to add random noise directly to the original image, as in SDEdit. However, we have observed that this can result in “semantic discrepancy” issues, wherein T2I diffusion models misinterpret the semantic relationships and generate content not present in the original image. We identify that the noise introduced by SDEdit disrupts the semantic integrity of the image, leading to unintended associations between unrelated regions after U-Net upsampling. Building on the widely-used latent diffusion model, Stable Diffusion, we propose a training-free, plug-and-play method to alleviate semantic discrepancy and enhance the fidelity of the translated image. By leveraging the deterministic nature of Denoising Diffusion Implicit Models (DDIMs) inversion, we correct the erroneous features and correlations from the original generative process with accurate ones from DDIM inversion. This approach alleviates semantic discrepancy and surpasses recent DDIM-inversion-based methods such as PnP with fewer priors, achieving a speedup of 11.2 times in experiments conducted on COCO, ImageNet, and ImageNet-R datasets across multiple I2I translation tasks. The codes are available at https://github.com/Sherlockyyf/Semantic_Discrepancy.

Local Search-Based Anytime Algorithms for Continuous Distributed Constraint Optimization Problems

Xin Liao, Khoi Hoang, Xin Luo

, Available online

[Abstract](9) [FullText HTML] (0) [PDF 653KB](2)

Abstract:

An Improved Repetitive-Control System Using a Complex-Coefficient Filter

Qicheng Mei, Jinhua She, Fei Long, Yanjun Shen

, Available online , doi: 10.1109/JAS.2024.124554

[Abstract](48) [FullText HTML] (0) [PDF 862KB](19)

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Event-Triggered Robust Parallel Optimal Consensus Control for Multiagent Systems

Qinglai Wei, Shanshan Jiao, Qi Dong, Fei-Yue Wang

, Available online

[Abstract](10) [FullText HTML] (0) [PDF 1989KB](3)

Abstract:
This paper highlights the utilization of parallel control and adaptive dynamic programming (ADP) for event-triggered robust parallel optimal consensus control (ETRPOC) of uncertain nonlinear continuous-time multiagent systems (MASs). First, the parallel control system, which consists of a virtual control variable and a specific auxiliary variable obtained from the coupled Hamiltonian, allows general systems to be transformed into affine systems. Of interest is the fact that the parallel control technique’s introduction provides an unprecedented perspective on eliminating the negative effects of disturbance. Then, an event-triggered mechanism is adopted to save communication resources while ensuring the system’s stability. The coupled Hamilton-Jacobi (HJ) equation’s solution is approximated using a critic neural network (NN), whose weights are updated in response to events. Furthermore, theoretical analysis reveals that the weight estimation error is uniformly ultimately bounded (UUB). Finally, numerical simulations demonstrate the effectiveness of the developed ETRPOC method.

Deep Synchronization Control for Grid-Forming Converters: A Reinforcement Learning Approach

Zhuorui Wu, Meng Zhang, Bo Fan, Yang Shi, Xiaohong Guan

, Available online

[Abstract](9) [FullText HTML] (0) [PDF 479KB](3)

Abstract:

Physical Layer Security Scheme With AoI-Awareness for Industrial IoT Based on Covert Communications

Yaping Li, Zhi-Xin Liu, Jia-Wei Su, Ya-Zhou Yuan

, Available online

[Abstract](6) [FullText HTML] (0) [PDF 452KB](2)

Abstract:

Self-Triggered Impulsive Control for Nonlinear Stochastic Systems

Tao Zhan, Yi Ji, Yabin Gao, Hongyi Li, Yuanqing Xia

, Available online

[Abstract](8) [FullText HTML] (0) [PDF 396KB](4)

Abstract:

Output Consensus of Heterogeneous Linear MASs via Adaptive Event-Triggered Feedback Combination Control

Shuo Yuan, Chengpu Yu, Jian Sun

, Available online

[Abstract](7) [FullText HTML] (0) [PDF 592KB](3)

Abstract:

From Singleton to Collaboration: Robust 3D Cooperative Positioning for Intelligent Connected Vehicles Based on Hybrid Range-Azimuth-Elevation Under Zero-Trust Driving Environments

Zhenyuan Zhang, Heng Qin, Darong Huang, Xin Fang, Mu Zhou, Shenghui Guo, Bo Mi

, Available online

[Abstract](18) [FullText HTML] (0) [PDF 8821KB](4)

Abstract:
Reliable and accurate cooperative positioning is vital to intelligent connected vehicles (ICVs), in which vehicle-vehicle relative measurements are integrated to provide stable location-aware services. However, in zero-trust autonomous driving environments, the possibility of measurement failures and malicious communication attacks tends to reduce positioning performance. With this in mind, this paper presents an ultra-wide bandwidth (UWB) based cooperative positioning system with the specific objective of ICV localization in zero-trust driving environments. Firstly, to overcome measurement degradation under non-line-of-sight (NLOS) propagation conditions, this study proposes a decentralized 3D cooperative positioning method based on a distributed Kalman filter (DKF) by integrating relative range-azimuth-elevation measurements, unlike the state-of-the-art methods that rely on only one single relative range information to update motion states. More specifically, in contrast to pioneering studies that mainly focus on the positioning problem arising from only one single type of communication attack (either false data injection (FDI) or denial of service (DoS)), we consider a more challenging case of secure cooperative state estimation under mixed FDI and DoS attacks. To this end, a singular-value decomposition (SVD)-assisted decoupled DKF algorithm is proposed in this work, in which a novel update-triggered inter-vehicular communication mechanism is introduced to ensure robust positioning performance against communication attacks while maintaining low transmission load between individuals. To verify the effectiveness in practical 3D NLOS scenarios, we design an intelligent connected multi-robot platform based on a robot operating system (ROS) and UWB technology. Consequently, extensive experimental results demonstrate its superiority and feasibility by achieving a high positioning accuracy of 0.68 m under adverse attacks, especially in the case of hybrid FDI and DoS attacks. In addition, several critical discussions, including the impact of attack parameters, resilience assessment, and a comparison with event-triggered methods, are provided in this work. Moreover, a demo video has been uploaded in the supplementary materials for a detailed presentation.

From Static and Dynamic Perspectives: A Survey on Historical Data Benchmarks of Control Performance Monitoring

Pengyu Song, Jie Wang, Chunhui Zhao, Biao Huang

, Available online , doi: 10.1109/JAS.2024.124902

[Abstract](14) [FullText HTML] (0) [PDF 2382KB](5)

Abstract:
In recent decades, control performance monitoring (CPM) has experienced remarkable progress in research and industrial applications. While CPM research has been investigated using various benchmarks, the historical data benchmark (HIS) has garnered the most attention due to its practicality and effectiveness. However, existing CPM reviews usually focus on the theoretical benchmark, and there is a lack of an in-depth review that thoroughly explores HIS-based methods. In this article, a comprehensive overview of HIS-based CPM is provided. First, we provide a novel static-dynamic perspective on data-level manifestations of control performance underlying typical controller capacities including regulation and servo: static and dynamic properties. The static property portrays time-independent variability in system output, and the dynamic property describes temporal behavior driven by closed-loop feedback. Accordingly, existing HIS-based CPM approaches and their intrinsic motivations are classified and analyzed from these two perspectives. Specifically, two mainstream solutions for CPM methods are summarized, including static analysis and dynamic analysis, which match data-driven techniques with actual controlling behavior. Furthermore, this paper also points out various opportunities and challenges faced in CPM for modern industry and provides promising directions in the context of artificial intelligence for inspiring future research.

SILIC: Intelligent On/Off Control for Networked Solar Insecticidal Lamps

Heyang Yao, Lei Shu, Yuli Yang, Miguel Martínez-García, Wei Lin

, Available online

[Abstract](11) [FullText HTML] (0) [PDF 1935KB](2)

Abstract:
The solar insecticidal lamp (SIL) is an innovative green control device. Nevertheless, a major challenge is often encountered when carrying out insecticidal work is low energy utilization efficiency. The substantial energy consumption required to turn on the SIL, coupled with the extension of insecticidal working time during the low pest activity periods, can result in low energy efficiency. Especially when the energy storage level is below 50%, the inefficient use of energy significantly reduces the effectiveness of pest control. Consequently, an ineffective on/off scheme for these lamps may lead to suboptimal energy utilization. In this paper, we present the solar insecticidal lamp Intelligent energy management scheme (SIL-IEMS) to address the challenge of inefficient energy utilization in the solar insecticidal lamp internet of things (SIL-IoT). SIL-IEMS primarily utilizes genetic algorithm (GA) and greedy algorithms to optimize insecticidal working time by considering constraints such as residual energy and the number of trap pests. Comparing SIL-IEMS to the traditional remote switching method (TRSM) and the solar insecticidal lamp genetic algorithm (SILGA), our simulation results showcase its superior energy efficiency and pest control effectiveness. Particularly noteworthy is the SILIEMS’s 17.6% increase in insecticidal efficiency compared to TRSM and 6% improvement over SILGA when the SIL begins with a remaining energy level of 15%.

Robust Offline Actor-Critic With On-policy Regularized Policy Evaluation

Shuo Cao, Xuesong Wang, Yuhu Cheng

, Available online

[Abstract](34) [FullText HTML] (0) [PDF 2837KB](12)

Abstract:
To alleviate the extrapolation error and instability inherent in Q-function directly learned by off-policy Q-learning (QL-style) on static datasets, this article utilizes the on-policy state-action-reward-state-action (SARSA-style) to develop an offline reinforcement learning (RL) method termed robust offline Actor-Critic with on-policy regularized policy evaluation (OPRAC). With the help of SARSA-style bootstrap actions, a conservative on-policy Q-function and a penalty term for matching the on-policy and off-policy actions are jointly constructed to regularize the optimal Q-function of off-policy QL-style. This naturally equips the off-policy QL-style policy evaluation with the intrinsic pessimistic conservatism of on-policy SARSA-style, thus facilitating the acquisition of stable estimated Q-function. Even with limited data sampling errors, the convergence of Q-function learned by OPRAC and the controllability of bias upper bound between the learned Q-function and its true Q-value can be theoretically guaranteed. In addition, the sub-optimality of learned optimal policy merely stems from sampling errors. Experiments on the well-known D4RL Gym-MuJoCo benchmark demonstrate that OPRAC can rapidly learn robust and effective task-solving policies owing to the stable estimate of Q-value, outperforming state-of-the-art offline RLs by at least 15%.

Feature-Driven Variational Mesh Denoising

Jianbin Yang, Cong Wang, Hui Hou, Mingyuan Wang, Xuelong Li

, Available online , doi: 10.1109/JAS.2024.124923

[Abstract](11) [FullText HTML] (0) [PDF 1811KB](2)

Abstract:
This work elaborates an innovative mesh denoising approach that combines feature recovery and denoising in an alternating manner. It proposes a feature-driven variational model and introduces an iterative scheme that alternates between feature recovery and the denoising process. The main idea is to estimate feature candidates, filter noisy face normals in the smooth (non-feature) domain, and utilize erosion and dilation operators on the feature candidates. By imposing connectivity constraints on normal vectors with large amplitude variations, the proposed scheme effectively removes noise and progressively recovers both sharp and small-scale features during the iterative process. To validate its effectiveness, this work conducts extensive numerical experiments on both simulated and real-scanned data. The results demonstrate significant improvements in noise reduction and feature preservation compared to existing methods.

On Resilience Against Cyber-Physical Uncertainties in Distributed Nash Equilibrium Seeking Strategies for Heterogeneous Games

Maojiao Ye

, Available online

[Abstract](19) [FullText HTML] (0) [PDF 2754KB](6)

Abstract:
This paper designs distributed Nash equilibrium seeking strategies for heterogeneous dynamic cyber-physical systems. In particular, we are concerned with parametric uncertainties in the control channel of the players. Moreover, the weights on communication links can be compromised by time-varying uncertainties, which can result from possibly malicious attacks, faults and disturbances. To deal with the unavailability of measurement of optimization errors, an output observer is constructed, based on which adaptive laws are designed to compensate for physical uncertainties. With adaptive laws, a new distributed Nash equilibrium seeking strategy is designed by further integrating consensus protocols and gradient search algorithms. Moreover, to further accommodate compromised communication weights resulting from cyber-uncertainties, the coupling strengths of the consensus module are designed to be adaptive. As a byproduct, the coupling strengths are independent of any global information. With theoretical investigations, it is proven that the proposed strategies are resilient to these uncertainties and players’ actions are convergent to the Nash equilibrium. Simulation examples are given to numerically validate the effectiveness of the proposed strategies.

Compensation for Heterogeneous Unknowns and Performance-Prescribed Consensus

Linzhen Yu, Yungang Liu

, Available online

[Abstract](17) [FullText HTML] (0) [PDF 1930KB](7)

Abstract:
In this paper, the MASs typically with heterogeneous unknown nonlinearities and nonidentical unknown control coefficients are studied. Although the model information of MASs is coarse, the leader-following consensus is still pursued, with a prescribed performance and zero consensus errors. Leveraging a powerful funnel control strategy, a fully distributed and completely relative-state-dependent protocol is designed. Distinctively, the time-varying function characterizing the performance boundary is introduced, not only to construct the funnel gains but also as an indispensable part of the protocol, enhancing the control ability and enabling the consensus errors to converge to zero (rather than a residual set). Remark that when control directions are unknown, coexisting with inherent system nonlinearities, it is essential to incorporate an additional compensation mechanism while imposing a hierarchical structure of communication topology for the control design and analysis. Simulation examples are given to illustrate the effectiveness of the theoretical results.

High-Order Control Barrier Function-Based Safety Control of Constrained Robotic Systems: An Augmented Dynamics Approach

Haijing Wang, Jinzhu Peng, Fangfang Zhang, Yaonan Wang

, Available online , doi: 10.1109/JAS.2024.124524

[Abstract](108) [FullText HTML] (0) [PDF 13298KB](43)

Abstract:
Although constraint satisfaction approaches have achieved fruitful results, system states may lose their smoothness and there may be undesired chattering of control inputs due to switching characteristics. Furthermore, it remains a challenge when there are additional constraints on control torques of robotic systems. In this article, we propose a novel high-order control barrier function (HoCBF)-based safety control method for robotic systems subject to input-output constraints, which can maintain the desired smoothness of system states and reduce undesired chattering vibration in the control torque. In our design, augmented dynamics are introduced into the HoCBF by constructing its output as the control input of the robotic system, so that the constraint satisfaction is facilitated by HoCBFs and the smoothness of system states is maintained by the augmented dynamics. This proposed scheme leads to the quadratic program (QP), which is more user-friendly in implementation since the constraint satisfaction control design is implemented as an add-on to an existing tracking control law. The proposed closed-loop control system not only achieves the requirements of real-time capability, stability, safety and compliance, but also reduces undesired chattering of control inputs. Finally, the effectiveness of the proposed control scheme is verified by simulations and experiments on robotic manipulators.

K-Corruption Intermittent Attacks for Violating the Codiagnosability

Ruotian Liu, Yihui Hu, Agostino Marcello Mangini, Maria Pia Fanti

, Available online , doi: 10.1109/JAS.2024.124680

[Abstract](23) [FullText HTML] (0) [PDF 2023KB](4)

Abstract:
In this work, we address the codiagnosability analysis problem of a networked discrete event system under malicious attacks. The considered system is modeled by a labeled Petri net and is monitored by a series of sites, in which each site possesses its own set of sensors, without requiring communication among sites or to any coordinators. A net is said to be codiagnosable with respect to a fault if at least one site could deduce the occurrence of this fault within finite steps. In this context, we focus on a type of malicious attack that is called stealthy intermittent replacement attack. The stealthiness demands that the corrupted observations should be consistent with the system’s normal behavior, while the intermittent replacement setting entails that the replaced transition labels must be recovered within a bounded of consecutive corrupted observations (called as K-corruption intermittent attack). Particularly, there exists a coordination between attackers that are separately effected on different sites, which holds the same corrupted observation for each common transition under attacks. From an attacker viewpoint, this work aims to design K-corruption intermittent attacks for violating the codiagnosability of systems. For this purpose, we propose an attack automaton to analyze K-corruption intermittent attack for each site, and build a new structure called complete attack graph that is used to analyze all the potential attacked paths. Finally, an algorithm is inferred to obtain the K-corruption intermittent attacks, and examples are given to show the proposed attack strategy.

Controllability of Multi-Relational Networks With Heterogeneous Dynamical Nodes

Lifu Wang, Zhaofei Li, Lianqian Cao, Ge Guo, Zhi Kong

, Available online

[Abstract](24) [FullText HTML] (0) [PDF 1139KB](8)

Abstract:
This paper studies the controllability of networked systems, in which the nodes are heterogeneous high-dimensional dynamical systems, and the links between nodes are multi-relational. Our aim is to find controllability criteria for heterogeneous networks with multi-relational links beyond those only applicable to networks with single-relational links. It is found a network with multi-relational links can be controllable even if each single-relational network topology is uncontrollable, and vice versa. Some sufficient and necessary conditions are derived for the controllability of multi-relational networks with heterogeneous dynamical nodes. For two typical multi-relational networks with star-chain topology and star-circle topology, some easily verified conditions are presented. For illustration and verification, several examples are presented. These findings provide practical insights for the analysis and control of multi-relational complex systems.

GPIO-Based Continuous Sliding Mode Control for Networked Control Systems Under Communication Delays With Experiments on Servo Motors

Kamal Rsetam, Zhenwei Cao, Zhihong Man, Xian-Ming Zhang

, Available online , doi: 10.1109/JAS.2024.124812

[Abstract](58) [FullText HTML] (0) [PDF 6049KB](22)

Abstract:
To handle input and output time delays that commonly exist in many networked control systems (NCSs), a new robust continuous sliding mode control (CSMC) scheme is proposed for the output tracking in uncertain single input-single-output (SISO) networked control systems. This scheme consists of three consecutive steps. First, although the network-induced delay in those systems can be effectively handled by using Pade approximation (PA), the unmatched disturbance cames out as another difficulty in the control design. Second, to actively estimate this unmatched disturbance, a generalized proportional integral observer (GPIO) technique is utilized based on only one measured state. Third, by constructing a new sliding manifold with the aid of the estimated unmatched disturbance and states, a GPIO-based CSMC is synthesized, which is employed to cope with not only matched and unmatched disturbances, but also network-induced delays. The stability of the entire closed-loop system under the proposed GPIO-based CSMC is detailedly analyzed. The promising tracking efficiency and feasibility of the proposed control methodology are verified through simulations and experiments on Quanser’s servo module for motion control under various test conditions.

Robust Pose Graph Optimization Against Outliers Using Consistency Credibility Factor

Jie Cai, Guoliang Wei, Wangyan Li, Yaolei Wang

, Available online , doi: 10.1109/JAS.2023.123897

[Abstract](16) [FullText HTML] (0) [PDF 513KB](2)

Abstract:

Cas-FNE: Cascaded Face Normal Estimation

Meng Wang, Jiawan Zhang, Jiayi Ma, Xiaojie Guo

, Available online

[Abstract](13) [FullText HTML] (0) [PDF 41212KB](3)

Abstract:
Capturing high-fidelity normals from single face images plays a core role in numerous computer vision and graphics applications. Though significant progress has been made in recent years, how to effectively and efficiently explore normal priors remains challenging. Most existing approaches depend on the development of intricate network architectures and complex calculations for in-the-wild face images. To overcome the above issue, we propose a simple yet effective cascaded neural network, called Cas-FNE, which progressively boosts the quality of predicted normals with marginal model parameters and computational cost. Meanwhile, it can mitigate the imbalance issue between training data and real-world face images due to the progressive refinement mechanism, and thus boost the generalization ability of the model. Specifically, in the training phase, our model relies solely on a small amount of labeled data. The earlier prediction serves as guidance for following refinement. In addition, our shared-parameter cascaded block employs a recurrent mechanism, allowing it to be applied multiple times for optimization without increasing network parameters. Quantitative and qualitative evaluations on benchmark datasets are conducted to show that our Cas-FNE can faithfully maintain facial details and reveal its superiority over state-of-the-art methods. The code is available at https://github.com/AutoHDR/CasFNE.git.

Distributed Fixed-Time Optimal Energy Management for Microgrids Based on a Dynamic Event-Triggered Mechanism

Feisheng Yang, Jiaming Liu, Xiaohong Guan

, Available online

[Abstract](20) [FullText HTML] (0) [PDF 1932KB](7)

Abstract:
The article investigates the optimal energy management (OEM) problem for microgrids. To figure out the OEM problem in fixed time and alleviate communication load with limited resources, this article devises a novel fixed-time stability lemma and a dynamic event-triggered (ET) fixed-time distributed OEM approach. Using Lyapunov stability theory, the distributed approach has been proven to converge in fixed time and the upper bound on convergence time can be derived without dependence on the initial states. The dynamic ET method is raised to dynamically adjust the triggering threshold and reduce communication redundancy. In addition, Zeno behavior is avoided. Simulations are given to show the effectiveness and advantage of the designed distributed OEM method.

A Game-Theoretic Approach to Solving the Roman Domination Problem

Xiuyang Chen, Changbing Tang, Zhao Zhang, Guanrong Chen

, Available online , doi: 10.1109/JAS.2023.123840

[Abstract](28) [FullText HTML] (0) [PDF 2230KB](7)

Abstract:
The Roman domination problem is an important combinatorial optimization problem that is derived from an old story of defending the Roman Empire and now regains new significance in cyber space security, considering backups in the face of a dynamic network security requirement. In this paper, firstly, we propose a Roman domination game (RDG) and prove that every Nash equilibrium (NE) of the game corresponds to a strong minimal Roman dominating function (S-RDF), as well as a Pareto-optimal solution. Secondly, we show that RDG is an exact potential game, which guarantees the existence of an NE. Thirdly, we design a game-based synchronous algorithm (GSA), which can be implemented distributively and converge to an NE in $ O(n)$ rounds, where n is the number of vertices. In GSA, all players make decisions depending on local information. Furthermore, we enhance GSA to be enhanced GSA (EGSA), which converges to a better NE in $ O(n^2)$ rounds. Finally, we present numerical simulations to demonstrate that EGSA can obtain a better approximate solution in promising computation time compared with state-of-the-art algorithms.

Optimal Production Capacity Matching for Blockchain-Enabled Manufacturing Collaboration With the Iterative Double Auction Method

Ying Chen, Feilong Lin, Zhongyu Chen, Changbing Tang, Cailian Chen

, Available online , doi: 10.1109/JAS.2024.124626

[Abstract](10) [FullText HTML] (0) [PDF 1850KB](3)

Abstract:
The increased demand for personalized customization calls for new production modes to enhance collaborations among a wide range of manufacturing practitioners who unnecessarily trust each other. In this article, a blockchain-enabled manufacturing collaboration framework is proposed, with a focus on the production capacity matching problem for blockchain-based peer-to-peer (P2P) collaboration. First, a digital model of production capacity description is built for trustworthy and transparent sharing over the blockchain. Second, an optimization problem is formulated for P2P production capacity matching with objectives to maximize both social welfare and individual benefits of all participants. Third, a feasible solution based on an iterative double auction mechanism is designed to determine the optimal price and quantity for production capacity matching with a lack of personal information. It facilitates automation of the matching process while protecting users’ privacy via blockchain-based smart contracts. Finally, simulation results from the Hyperledger Fabric-based prototype show that the proposed approach increases social welfare by 1.4% compared to the Bayesian game-based approach, makes all participants profitable, and achieves 90% fairness of enterprises.

Disturbance Rejection for Systems With Uncertainties Based on Fixed-Time Equivalent-Input-Disturbance Approach

Qun Lu, Xiang Wu, Jinhua She, Fanghong Guo, Li Yu

, Available online , doi: 10.1109/JAS.2024.124650

[Abstract](177) [FullText HTML] (0) [PDF 2577KB](52)

Abstract:
This paper presents a fixed-time equivalent-input-disturbance (EID) approach to deal with the problem of robust output-feedback control for perturbed uncertain systems. This method uses the basic structure of the conventional EID approach and treats uncertainties and disturbances as a lumped disturbance on the control-input channel. A fixed-time state observer enables state estimation, which resolves the causality issue in an EID-based control system, is finished in a fixed time. An implicit Lyapunov function, the homogeneity with dilation, the input-to-state stability, and the small-gain theorem are used to analyze the convergence and robustness of the EID-based system with measurement noise. Numerical and experimental results are presented to demonstrate the effectiveness and superiority of the proposed method.

Strong Current-State Opacity Verification of Discrete-Event Systems Modeled With Time Labeled Petri Nets

Tao Qin, Li Yin, Gaiyun Liu, Naiqi Wu, Zhiwu Li

, Available online , doi: 10.1109/JAS.2024.124560

[Abstract](32) [FullText HTML] (0) [PDF 1575KB](11)

Abstract:
This paper addresses the verification of strong current-state opacity with respect to real-time observations generated from a discrete-event system that is modeled with time labeled Petri nets. The standard current-state opacity cannot completely characterize higher-level security. To ensure the higher-level security requirements of a time-dependent system, we propose a strong version of opacity known as strong current-state opacity. For any path (state-event sequence with time information) π derived from a real-time observation that ends at a secret state, the strong current-state opacity of the real-time observation signifies that there is a non-secret path with the same real-time observation as π. We propose general and non-secret state class graphs, which characterize the general and non-secret states of time-dependent systems, respectively. To capture the observable behavior of non-secret states, a non-secret observer is proposed. Finally, we develop a structure called a real-time concurrent verifier to verify the strong current-state opacity of time labeled Petri nets. This approach is efficient since the real-time concurrent verifier can be constructed by solving a certain number of linear programming problems.

Chattering-Free Fault-Tolerant Cluster Control and Fault Direction Identification for HIL UAV Swarm With Pre-Specified Performance

Pei-Ming Liu, Xiang-Gui Guo, Jian-Liang Wang, Daniel Coutinho, Lihua Xie

, Available online , doi: 10.1109/JAS.2024.124827

[Abstract](87) [FullText HTML] (0) [PDF 2944KB](21)

Abstract:
In this paper, the problem of pre-specified performance fault-tolerant cluster consensus control and fault direction identification is solved for the human-in-the-loop (HIL) swarm unmanned aerial vehicles (UAVs) in the presence of possible nonidentical and unknown direction faults (NUDFs) in the yaw channel. The control strategy begins with the design of a pre-specified performance event-triggered observer for each individual UAV. These observers estimate the outputs of the human controlled UAVs, and simultaneously achieve the distributed design of actual control signals as well as cluster consensus of the observer output. It is worth mentioning that these observers require neither the high-order derivatives of the human controlled UAVs’ output nor a priori knowledge of the initial conditions. The fault-tolerant controller realizes the pre-specified performance output regulation through error transformation and the Nussbaum function. It should be pointed out that there are no chattering caused by the jump of the Nussbaum function when a reverse fault occurs. In addition, to provide a basis for further solving the problem of physical malfunctions, a fault direction identification algorithm is proposed to accurately identify whether a reverse fault has occurred. Simulation results verify the effectiveness of the proposed control and fault direction identification strategies when the reverse faults occur.

Unifying Fixed Time and Prescribed Time Control for Strict-Feedback Nonlinear Systems

Xiang Chen, Yujuan Wang, Yongduan Song

, Available online , doi: 10.1109/JAS.2024.124401

[Abstract](27) [FullText HTML] (0) [PDF 1308KB](12)

Abstract:
This paper investigates the prescribed-time tracking control problem for a class of multi-input multi-output (MIMO) nonlinear strict-feedback systems subject to non-vanishing uncertainties. The inherent unmatched and non-vanishing uncertainties make the prescribed-time control problem become much more nontrivial. The solution to address the challenges mentioned above involves incorporating a prescribed-time filter, as opposed to a finite-time filter, and formulating a prescribed-time Lyapunov stability lemma (Lemma 5). The prescribed-time Lyapunov stability lemma is based on time axis shifting time-varying yet bounded gain, which establishes a novel link between the fixed-time and prescribed-time control method. This allows the restriction condition that the time-varying gain function must satisfy as imposed in most exist prescribed-time control works to be removed. Under the proposed control method, the desire trajectory is ensured to closely track the output of the system in prescribed time. The effectiveness of the theoretical results are verified through numerical simulation.

Linear Programming-Based Consensus of Positive Continuous-Time Multi-Agent Systems

Junfeng Zhang, Fengyu Lin, Shihong Ding, Wei Xing

, Available online

[Abstract](15) [FullText HTML] (0) [PDF 468KB](1)

Abstract:

Level Curve Tracking via Robust RL-Guided Model Predictive Control

Zhuo Li, Yunlong Guo, Gang Wang, Wei Chen

, Available online

[Abstract](20) [FullText HTML] (0) [PDF 823KB](3)

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Consensus-Based Distributed Secondary Control of Microgrids: A Pre-assigned Time Sliding Mode Approach

Xiangyong Chen, Shunwei Hu, Xiangpeng Xie, Jianlong Qiu

, Available online

[Abstract](17) [FullText HTML] (0) [PDF 546KB](12)

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Human Observation-Inspired Universal Image Acquisition Paradigm Integrating Multi-Objective Motion Planning and Control for Robotics

Haotian Liu, Yuchuang Tong, Zhengtao Zhang

, Available online

[Abstract](17) [FullText HTML] (0) [PDF 24624KB](6)

Abstract:
Image acquisition stands as a prerequisite for scrutinizing surfaces inspection in industrial high-end manufacturing. Current imaging systems often exhibit inflexibility, being confined to specific objects and encountering difficulties with diverse industrial structures lacking standardized computer-aided design (CAD) models or in instances of deformation. Inspired by the multidimensional observation of humans, our study introduces a universal image acquisition paradigm tailored for robotics, seamlessly integrating multi-objective optimization trajectory planning and control scheme to harness measured point clouds for versatile, efficient, and highly accurate image acquisition across diverse structures and scenarios. Specifically, we introduce an energy-based adaptive trajectory optimization (EBATO) method that combines deformation and deviation with dual-threshold optimization and adaptive weight adjustment to improve the smoothness and accuracy of imaging trajectory and posture. Additionally, a multi-optimization control scheme based on a meta-heuristic beetle antennal olfactory recurrent neural network (BAORNN) is proposed to track the imaging trajectory while addressing posture, obstacle avoidance, and physical constraints in industrial scenarios. Simulations, real-world experiments, and comparisons demonstrate the effectiveness and practicality of the proposed paradigm.

Interference Suppression and Jitter Elimination Ability-Based Adaption Tracking Guidance for Robotic Fishes

Dongfang Li, Jie Huang, Rob Law, Xin Xu, Limin Zhu, Edmond Q. Wu

, Available online , doi: 10.1109/JAS.2024.124632

[Abstract](28) [FullText HTML] (0) [PDF 4070KB](7)

Abstract:
This work presents an adaptive tracking guidance method for robotic fishes. The scheme enables robots to suppress external interference and eliminate motion jitter. An adaptive integral surge line-of-sight guidance rule is designed to eliminate dynamics interference and sideslip issues. Limited-time yaw and surge speed observers are reported to fit disturbance variables in the model. The approximation values can compensate for the system’s control input and improve the robots’ tracking accuracy. Moreover, this work develops a terminal sliding mode controller and third-order differential processor to determine the rotational torque and reduce the robots’ run jitter. Then, Lyapunov’s theory proves the uniform ultimate boundedness of the proposed method. Simulation and physical experiments confirm that the technology improves the tracking error convergence speed and stability of robotic fishes.

High-Order Fully Actuated System Models for Strict-Feedback Systems With Increasing Dimensions

Xiang Xu, Guang-Ren Duan

, Available online , doi: 10.1109/JAS.2024.124599

[Abstract](31) [FullText HTML] (0) [PDF 878KB](13)

Abstract:
This paper mainly addresses control problems of strict-feedback systems (SFSs) with increasing dimensions. Compared with the commonly-considered SFSs where the subsystems have the same dimension, we aim to handle more complex cases, i.e., the subsystems in the considered SFSs are assumed to have increasing dimensions. By transforming the systems into high-order fully-actuated system (HOFAS) models, the stabilizing controllers can be directly given. Besides first-order SFSs, second-order and high-order SFSs are also considered.

Release Power of Mechanism and Data Fusion: A Hierarchical Strategy for Enhanced MIQ-Related Modeling and Fault Detection in BFIP

Siwei Lou, Chunjie Yang, Zhe Liu, Shaoqi Wang, Hanwen Zhang, Ping Wu

, Available online , doi: 10.1109/JAS.2024.124821

[Abstract](46) [FullText HTML] (0) [PDF 18758KB](17)

Abstract:
Data-driven techniques are reshaping blast furnace iron-making process (BFIP) modeling, but their “black-box” nature often obscures interpretability and accuracy. To overcome these limitations, our mechanism and data co-driven strategy (MDCDS) enhances model transparency and molten iron quality (MIQ) prediction. By zoning the furnace and applying mechanism-based features for material and thermal trends, coupled with a novel stationary broad feature learning system (StaBFLS), interference caused by nonstationary process characteristics are mitigated and the intrinsic information embedded in BFIP is mined. Subsequently, by integrating stationary feature representation with mechanism features, our temporal matching broad learning system (TMBLS) aligns process and quality variables using MIQ as the target. This integration allows us to establish process monitoring statistics using both mechanism and data-driven features, as well as detect modeling deviations. Validated against real-world BFIP data, our MDCDS model demonstrates consistent process alignment, robust feature extraction, and improved MIQ modeling—yielding better fault detection. Additionally, we offer detailed insights into the validation process, including parameter baselining and optimization. Details of the code are available online.¹

Federated Experiments: Generative Causal Inference Powered by LLM-based Agents Simulation and RAG-based Domain Docking

De-Yu Zhou, Xiao Xue, Qun Ma, Chao Guo, Li-Zhen Cui, Yong-Lin Tian, Jing Yang, Fei-Yue Wang

, Available online , doi: 10.1109/JAS.2024.124671

[Abstract](59) [FullText HTML] (0) [PDF 682KB](46)

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Distributed State and Fault Estimation for Cyber-Physical Systems Under DoS Attacks

Limei Liang, Rong Su, Haotian Xu

, Available online , doi: 10.1109/JAS.2024.124527

[Abstract](48) [FullText HTML] (0) [PDF 507KB](25)

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Multi-Interval-Aggregation Failure Point Approximation for Remaining Useful Life Prediction

Linchuan Fan, Xiaolong Chen, Shuo Li, Yi Chai

, Available online , doi: 10.1109/JAS.2024.124593

[Abstract](75) [FullText HTML] (0) [PDF 825KB](26)

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Data-Driven Iterative Learning Consensus Tracking Based on Robust Neural Models for Unknown Heterogeneous Nonlinear Multiagent Systems With Input Constraints

Chong Zhang, Yunfeng Hu, TingTing Wang, Xun Gong, Hong Chen

, Available online

[Abstract](44) [FullText HTML] (0) [PDF 409KB](16)

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Optimal Secure Control of Networked Control Systems Under False Data Injection Attacks: A Multi-Stage Attack-Defense Game Approach

Dajun Du, Yi Zhang, Baoyue Xu, Minrui Fei

, Available online , doi: 10.1109/JAS.2023.124005

[Abstract](55) [FullText HTML] (0) [PDF 878KB](20)

Abstract:

Distributed Optimal Formation Control of Unmanned Aerial Vehicles: Theory and Experiments

Gang Wang, Zhenhong Wei, Peng Li

, Available online , doi: 10.1109/JAS.2024.124518

[Abstract](91) [FullText HTML] (0) [PDF 4081KB](36)

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Accumulative-Error-Based Event-Triggered Control for Discrete-Time Linear Systems: A Discrete-Time Looped Functional Method

Xian-Ming Zhang, Qing-Long Han, Xiaohua Ge, Bao-Lin Zhang

, Available online , doi: 10.1109/JAS.2024.124476

[Abstract](180) [FullText HTML] (0) [PDF 1585KB](14)

Abstract:
This paper is concerned with event-triggered control of discrete-time systems with or without input saturation. First, an accumulative-error-based event-triggered scheme is devised for control updates. When the accumulated error between the current state and the latest control update exceeds a certain threshold, an event is triggered. Such a scheme can ensure the event-generator works at a relatively low rate rather than falls into hibernation especially after the system steps into its steady state. Second, the looped functional method for continuous-time systems is extended to discrete-time systems. By introducing an innovative looped functional that links the event-triggered scheme, some sufficient conditions for the co-design of control gain and event-triggered parameters are obtained in terms of linear matrix inequalities with a couple of tuning parameters. Then, the proposed method is applied to discrete-time systems with input saturation. As a result, both suitable control gains and event-triggered parameters are also co-designed to ensure the system trajectories converge to the region of attraction. Finally, an unstable reactor system and an inverted pendulum system are given to show the effectiveness of the proposed method.

Non-Singular Practical Fixed-time Prescribed Performance Adaptive Fuzzy Consensus Control for Multi-Agent Systems Based on an Observer

Chi Ma, Dianbiao Dong

, Available online , doi: 10.1109/JAS.2024.124428

[Abstract](81) [FullText HTML] (0) [PDF 2534KB](37)

Abstract:
In this paper, the problem of non-singular fixed-time control with prescribed performance is studied for multi-agent systems characterized by uncertain states, nonlinearities, and non-strict feedback. To mitigate the nonlinearity, a fuzzy logic algorithm is applied to approximate the intrinsic dynamics of the system. Furthermore, a fuzzy logic system state observer based on leader state information is designed to address the partial unobservability of followers. Subsequently, the power integral method is incorporated into the backstepping approach to avoid singularities in the fixed-time controller. A command filter method is introduced into the standard backstepping approach to reduce the computational complexity of controller design. Then, a non-singular fixed-time adaptive control strategy with prescribed performance is proposed by constraining the tracking error within a prescribed range. Rigorous theoretical analysis ensures the convergence of consensus error in the multi-agent system to the prescribed performance region within a fixed time. Finally, the practicality of the algorithm is validated through numerical simulations.

Distributed Finite-Time Formation Control of Multiple Mobile Robot Systems Without Global Information

Xunhong Sun, Haibo Du, Weile Chen, Wenwu Zhu

, Available online , doi: 10.1109/JAS.2023.123981

[Abstract](84) [FullText HTML] (0) [PDF 564KB](38)

Abstract:

Semi-Decentralized Convex Optimization on

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Weijian Li, Peng Yi

, Available online , doi: 10.1109/JAS.2024.124356

[Abstract](48) [FullText HTML] (0) [PDF 377KB](11)

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New Controllability Criteria for Linear Switched and Impulsive Systems

Jiayuan Yan, Bin Hu, Zhi-Hong Guan, Yandong Hou, Lei Shi

, Available online , doi: 10.1109/JAS.2024.124272

[Abstract](34) [FullText HTML] (0) [PDF 356KB](9)

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Set-Valued State Estimation of Nonlinear Discrete-Time Systems and Its Application to Attack Detection

Hao Liu, Qing-Long Han, Yuzhe Li

, Available online

[Abstract](84) [FullText HTML] (0) [PDF 1560KB](23)

Abstract:
This paper investigates set-valued state estimation of nonlinear systems with unknown-but-bounded (UBB) noises based on constrained polynomial zonotopes which is utilized to characterize non-convex sets. First, properties of constrained polynomial zonotopes are provided and the order reduction method is given to reduce the computational complexity. Then, the corresponding improved prediction-update algorithm is proposed so that it can be adapted to non-convex sets. Based on generalized intersection, the utilization of set-based estimation for attack detection is analyzed. Finally, an example is given to show the efficiency of our results.

A Novel Vibration-Based Self-Adapting Method to Acquire Real-Time Following Distance for Virtually Coupled Trains

Qinglai Zhang, Jianmin Gao, Qing Wu, Qinglie He, Libin Tie, Wanming Zhai, Shengyang Zhu

, Available online , doi: 10.1109/JAS.2024.124326

[Abstract](66) [FullText HTML] (0) [PDF 3816KB](10)

Abstract:
Virtual coupling (VC) is an emerging technology for addressing the shortage of rail transportation capacity. As a crucial enabling technology, the VC-specific acquisition of train information, especially train following distance (TFD), is underdeveloped. In this paper, a novel method is proposed to acquire real-time TFD by analyzing the vibration response of the front and following trains, during which only onboard accelerometers and speedometers are required. In contrast to the traditional arts of train positioning, this method targets a relative position between two adjacent trains in VC operation, rather than the global positions of the trains. For this purpose, an adaptive system containing three strategies is designed to cope with possible adverse factors in train operation. A vehicle dynamics simulation of a heavy-haul railway is implemented for the evaluation of feasibility and performance. Furthermore, a validation is conducted using a set of data measured from in-service Chinese high-speed trains. The results indicate the method achieves satisfactory estimation accuracy using both simulated and actual data. It has favorable adaptability to various uncertainties possibly encountered in train operation. Additionally, the method is preliminarily proven to adapt to different locomotive types and even different rail transportation modes. In general, such a method with good performance, low-cost, and easy implementation is promising to apply.