This paper investigates the recoil control of the deepwater drilling riser system with nonlinear tension force and energy-bounded friction force under the circumstances of limited network resources and unreliable communication. Different from the existing linearization modeling method, a triangle-based polytope modeling method is applied to the nonlinear riser system. Based on the polytope model, to improve resource utilization and accommodate random data loss and communication delay, an asynchronous gain-scheduled control strategy under a hybrid event-triggered scheme is proposed. An asynchronous linear parameter-varying system that blends input delay and impulsive update equation is presented to model the nonlinear networked recoil control system, where the asynchronous deviation bounds of scheduling parameters are calculated. Resorting to the Lyapunov–Krasovskii functional method, some solvable conditions of disturbance attenuation analysis and recoil control design are derived such that the resulting networked system is exponentially mean-square stable with prescribed H ∞ performance. The obtained numerical results verified that the proposed nonlinear networked control method can achieve a better recoil response of the riser system with less transmission data compared with the linear control method.

This article presents an asynchronous distributed interval filtering method for discrete-time positive Markov jump linear systems (MJLSs) with bounded disturbance under the denial-of-service attack. By designing an asynchronous switching-distributed mechanism that depends on a randomly occurred attack, the proposed positive filter can monitor the real-time range of estimated states against the attack. The filtering error systems are modeled as a class of MJLSs with two attack-dependent Markov chains. Some analysis and design results are derived such that the error systems are positive and stochastically internally stable with satisfied$l_{1}$-gain performance. The remote power monitoring in telecommunication systems is used for numerical verification.

This paper focuses on the network-based modeling and proportional-integral (PI) control for a continuous-time direct-drive-wheel system in a wireless network environment. The developed system can simplify configuration, reduce bus cables, and realize vehicle height adjustment. A novel network-based model is first established by constructing a PI control system and taking network-induced delays and stochastic packet dropouts into account. By using two different artificial delays to characterize the update of proportional and integral control signals, the network-based PI control system is modeled as a stochastic impulsive system with two input delays and reset equations at updating instants. Then, through involving the reset states and the relationship among two delayed states and the current state in the discontinuous Lyapunov-Krasovskii functional and actively introducing the upper bounds of nonzero network-induced delays, some exponential mean-square stability and H∞performance conditions with less conservatism are derived in terms of tractable linear matrix inequalities. An algorithm is presented to determine the minimum H∞performance and the corresponding PI control parameters by combining a particle swarm optimization technique with the performance condition. These results can be extended to a network-based PI control of general continuous-time linear systems. A ZigBee-based network simulation platform is finally built and some simulation results are provided to validate the proposed methods.

This paper investigates network-based output tracking control for a T-S fuzzy system that can not be stabilized by a nondelayed fuzzy static output feedback controller, but can be stabilized by a delayed fuzzy static output feedback controller. By intentionally introducing a communication network that produces proper network-induced delays in the feedback control loop, a stable and satisfactory tracking control can be ensured for the T-S fuzzy system. Due to the presence of network-induced delays, the fuzzy system and the fuzzy tracking controller operate in an asynchronous way. Taking the asynchronous operation and network-induced delays into consideration, the network-based tracking control system is modeled as an asynchronous T-S fuzzy system with an interval time-varying delay. A new delay-dependent criterion for L2 -gain tracking performance is derived by using the deviation bounds of asynchronous normalized membership functions and a complete Lyapunov-Krasovskii functional. Applying a particle swarm optimization technique with the feasibility of the derived criterion, a novel design algorithm is presented to determine the minimum L2 -gain tracking performance and control gains simultaneously. The effectiveness of the proposed method is illustrated by performing network-based output tracking control of a Duffing-Van der Pol's oscillator.

An image-based strategy visual servo control via Hamiltonian approach for a binocular camera-in-hand robotic system is considered. A new Hamiltonian realization is designed for the visual servo control systems which consider the dynamics of the robotic systems. The designed system can be modeled as a port-controlled Hamiltonian (PCH) system. We give the stability analysis about the PCH system. Simulation experiments illustrate the theory and show the effectiveness of the proposed designs.

This paper investigates the network-based H∞control for a class of dual-rate sampled-data systems. The system states are assumed to be sampled by two different sampling periods, and the sampled states are transmitted to a controller/actuator through a communication network. Taking network-induced delays, packet dropouts and dual-rate behaviors into consideration, a state observer is introduced to produce the estimates of the system states by using available sampled states, and a state feedback controller based on the observer estimates is constructed to stabilize the systems. The network-based dual-rate sampled-data system is modeled as a system with two interval time-varying delays. Some delay-dependent criteria for the H∞performance and the existence of the observer-based controller are derived by using a Lyapunov-Krasovskii functional method. A numerical example is provided to demonstrate the effectiveness of the proposed method.

This paper considers H∞tracking control for a class of network-based T-S fuzzy systems with available asynchronous constraints on membership functions. Using a fuzzy controller associated with available sampled-data of both premise variables and feedback states, the network-based control system is equivalent to an asynchronous T-S fuzzy system with an interval time-varying sawtooth delay. Notice that the routine relaxation methods in traditional T-S fuzzy systems can not be used for stability analysis and controller design of the asynchronous fuzzy system since common product terms of membership functions can not be grouped. Instead, a new relaxation method is proposed by using asynchronous constraints on fuzzy membership functions to introduce some free weighting matrices. By using the proposed relaxation method and a new discontinuous Lyapunov-Krasovskii functional, some criteria on H∞tracking performance analysis and controller design are derived. Compared with the existing results, the derived criteria are of less conservatism and allow the existence of a network-based fuzzy controller with different gains, which can ensure a better H∞tracking performance. The effectiveness of the proposed method is illustrated by an example.

This paper is concerned with network-based static output feedback tracking control for a class of nonlinear systems that can not be stabilized by a static output feedback controller without a time-delay, but can be stabilized by a delayed static output feedback controller. For such systems, network-induced delay is intentionally introduced in the feedback loop to produce a stable and satisfactory tracking control. The nonlinear network-based control system is represented by an asynchronous T-S fuzzy system with an interval time-varying sawtooth delay due to sample-and-hold behaviors and network-induced delays. A new discontinuous complete Lyapunov-Krasovskii functional, which makes use of the lower bound of network-induced delays, the sawtooth delay and its upper bound, is constructed to derive a delay-dependent criterion on H∞tracking performance analysis. Since routine relaxation methods in traditional T-S fuzzy systems can not be employed to reduce the conservatism of the stability criterion, a new relaxation method is proposed by using asynchronous constraints on fuzzy membership functions to introduce some free-weighting matrices. Based on the feasibility of the derived criterion, a particle swarm optimization algorithm is presented to search the minimum H∞tracking performance and static output feedback gains. An illustrative example is provided to show the effectiveness of the proposed method.

This paper investigates network-based fuzzy static output feedback tracking control for Van der Pol's oscillators using positive effects of network-induced delays. Taking network-induced delays into account, the network-based nonlinear control system is modeled as an asynchronous T-S fuzzy system with an interval time-varying delay. A discontinuous complete Lyapunov-Krasovskii functional and a new relaxation method involving the asynchronous constraints on membership functions are proposed to derive some delay-dependent criteria on H∞tracking performance analysis and controller design of the asynchronous fuzzy system. The effectiveness of the proposed method is shown by a numerical example.

This paper investigates the fuzzy tracking control problem for a class of nonlinear networked control systems (NCSs) with a prescribed H(infinity) tracking performance. Such NCSs consist of a nonlinear controlled plant, a tracked plant, sensors, a controller, and an actuator. A Takagi-Sugeno fuzzy model is employed to represent the nonlinear controlled plant in the NCSs, and a tracked plant is described by a linear stable reference model. In transmission, both network-induced delay and packet losses are considered. By the parallel distributed compensation technique, a novel tracking model of the nonlinear NCSs is first established. Based on Lyapunov stability theory, a control design method that guarantees the prescribed H(infinity) tracking performance of the nonlinear NCSs is developed in terms of linear matrix inequalities. Finally, a numerical example is given to illustrate the effectiveness of our result.