Control of interconnected systems with sensor delay based on decentralized adaptive neural dynamic surface method

Abstract

In this article, an adaptive neural network is proposed for the tracking control problem of unknown nonlinear interconnected systems with inaccessible states and sensor delays based on dynamic surface strategy. The system has unknown nonlinearities and immeasurable states. Thus, a neural network state observer based on delayed outputs of subsystems is applied. The main difficulty in obtaining local observers’ gains is that undelayed outputs are not available. As a result, by utilizing proper Lyapunov–Krasovskii functionals in dynamic surface design procedures, the gains of local observers are given in terms of linear matrix inequalities. Then, appropriate changes in coordinates are defined using delayed outputs, observed states, and filtered virtual controls for the purpose of designing dynamic surface controllers. Subsequently, proper Lyapunov–Krasovskii functionals are introduced to deal with sensor delays and obtain control laws and stability criteria. Furthermore, the proposed decentralized control scheme can suitably conquer the decentralized tracking problem of unknown large-scale systems with sensor delays and guarantee that all the signals in the closed-loop interconnected systems be uniformly ultimately bounded. Finally, to show the effectiveness and efficiency of the proposed approach, the theoretic achievements are employed to design a controller for a double-inverted pendulum system and a cascade chemical reactor system.

Composite adaptive control based on historical data for electro-hydraulic system driven by dual servo motor-pump with unknown disturbance

“…In the proposed method, the exciting vector is integrated by a time interval expressed as equation ( 14), and it can be noticed that the historical data and instantaneous data are exploited to update the parameter estimateû. For the hydraulic system driven by the control law as in equation ( 4) with adaptive law given by equation (12), if there exists T e , t d and g, and the interval excitation condition is satisfied, the closed-loop hydraulic system could achieve the exponential stability in the sense of the convergent tracking error e i and estimation errorũ i , and the proof is provided in the stability analysis section.…”

“…The artificial intelligence methods were also used to solve the control problem of the uncertain and nonlinear systems. 11,12 Besides, the disturbance including friction and unmeasurable load force of EHS have an impact on precision motion control of the system, and some research has taken those factors into account when designing the controller. Yao et al 13 employed the LuGre model-based friction expression to compensate, and estimated the unmeasurable state variables by a dual state observer.…”

“…The artificial intelligence methods were also used to solve the control problem of the uncertain and nonlinear systems. 11,12…”

Fixed-time leader-following synchronization in delayed network via non-chattering nonlinear control

“…The delayed network is a class of infinite dimensional systems and has more complicated dynamics from the point of view of synchronization control. There are many literatures to study the synchronization in different kinds of time delay, such as the delay in the state, the input and output (Baigzadehnoe et al, 2018, 2021; Dastres et al, 2020; Li and Cao, 2015; Rahmani et al, 2020; Xu et al, 2019). However, there are still relatively few in the fixed-time synchronization (FTS).…”

Design of State Feedback LQR Based Dual Mode Fractional-Order PID Controller using Inertia Weighted PSO Algorithm: For Control of an Underactuated System

“…The robust stabilization of the IP system is proposed in [2], in which an amplified LQR is used to solve the parametric uncertainties and unmodeled dynamics. An adaptive NN is used for control of the IP system [3], in which Lyapunov functionals have been introduced to obtain stability conditions. In [4], the fuzzy logic controller is proposed for a two-wheeled IP.…”