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In this paper, we propose a fault detection, fault isolation, and control reconfiguration (FDIR) for multiple automated guided vehicles (AGVs) to accomplish object transportation under actuator failures. Firstly, the observers are designed for the AGVs to detect any occurring faults in actuators. Secondly, banks of observers are employed to isolate the broken actuators. Finally, according to the isolation results, the controllers are reconfigured to accommodate the faults. The stability of the proposed methods is verified using the Lyapunov technique. It is worth noting that the proposed FDIR method considers the uncertainties in system dynamics, enhancing its practicality and convenience for implementation. The effectiveness of the proposed algorithm is demonstrated via both numerical and experimental examples involving multiple omnidirectional AGVs experiencing actuator faults. [ABSTRACT FROM AUTHOR]

Cooperative robotics has gained considerable traction in the industrial sector with the expeditious use of multi-agent systems. Containment control is an emergent topic in cooperative multi-agent systems, with applications in areas such as warehouse robotics, inventory management, and transportation. Containment control is an amalgamation of formation and consensus control, which predominantly uses groups of multiple agents assigned as leaders and followers. This survey paper provides a comprehensive overview of key topics in containment control of multi-agent systems ranging from containment concepts to controllers. The paper discusses the role of communication and network topologies, the importance of accurate sensor measurements and agent dynamics, and various controller design and stability analysis techniques. The paper concludes by highlighting the promising research directions and challenges in the field along with real-world applications. Overall, this survey paper provides a valuable resource for researchers, practitioners, and students interested in the development of advanced multi-agent systems with containment control. [ABSTRACT FROM AUTHOR]

This paper focuses the design of resilient control for networked control systems with an adaptive event-triggered mechanism in the presence of denial-of-service attacks, actuator saturation and actuator faults. The model for denial-of-service attacks (DoS-As) in networked control systems, which mainly destroy the control channel and occur aperiodically with an unknown attack strategy, is constructed. An adaptive event-triggered mechanism (AETM) is introduced to reduce unimportant communication transmissions in a network provided adaptive varying threshold while maintaining satisfactory system performance. By using the Lyapunov function approach, linear matrix inequality (LMI)-based sufficient conditions are obtained to ensure the exponential stability and satisfying the prescribed performance index of the closed-loop systems under DoS-As. Moreover, the feasibility of the jointly developed schemes for the control gain and event-triggered parameters is calculated using the presented LMIs. The potentiality of the proposed scheme is validated using a numerical example. [ABSTRACT FROM AUTHOR]

It is well understood that motor dysfunctions in patients can be restored through a certain amount of repetitive training. Robots and virtual reality offer an excellent solution to incentivize and optimize training intensity while also reducing the workload for therapists. In this paper, leveraging virtual reality technologies and haptic robots, we have developed a cost-effective robot-assisted training system and three training exercises for hand rehabilitation. The Unity game engine was utilized to create training scenarios where hand avatars interact with virtual objects. Off-the-shelf haptic robots were employed to manipulate the hand avatars, enabling completion of training tasks with a realistic tactile experience. Haptic feedback is rendered using impedance control laws. Additionally, to address the needs of both patients and therapists we propose to employ robot-assisted force and feedback force. These mechanisms are designed to provide assistance to patients during tasks if needs and to transmit the patient's force feedback to the therapist, facilitating comprehensive interaction and communication between the two parties. Several experiments were conducted involving six healthy subjects, who used electrode stimulation to simulate impaired limbs, to demonstrate the effectiveness of the proposed training frameworks. [ABSTRACT FROM AUTHOR]

This work studies the event-based fault-tolerant control issue of networked control systems with actuator saturation, resilient event-triggering, randomly occurring nonlinearities, and denial-of-service jamming attacks (DoS-JAs). Initially, we aim to design a resilient event-triggered (ET) communication scheme under the attacks, proposed by the known period of the jamming signal. The period values occur in uniform lower bounds for the jammer's sleeping time. Next, a closed-loop networked control system is constructed as a switched-control strategy subject to state-delay, in addition to actuator saturation, actuator faults, DoS jamming attack, parameter uncertainty and resilient ET control schemes. Based on the Lyapunov stability theory, piecewise property and Wirtinger-based integral inequality, a set of sufficient conditions are obtained to ensure that the resulting closed-loop switched system is exponentially stable against DoS jamming attacks and satisfies mixed H ∞ and passivity performance index. Furthermore, the efficacy of the proposed method is demonstrated through simulated examples based on the two practical applications of satellite control systems and aircraft flight control systems. [ABSTRACT FROM AUTHOR]

This paper investigates the problem of networked control system for nonlinear robotic manipulators under time delays and packet loss by using passivity technique. With the utilisation of wave variables and a passive remote controller, the networked robotic system is demonstrated to be stable with guaranteed position regulation. For the input/output signals of robotic systems, a discretisation block is exploited to convert continuous-time signals to discrete-time signals, and vice versa. Subsequently, we propose a packet management, called wave-variable modulation, to cope with the proposed networked robotic system under time delays and packet losses. Numerical examples and experimental results are presented to demonstrate the performance of the proposed wave-variable-based networked robotic systems. [ABSTRACT FROM PUBLISHER]