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This paper considers the leader-following consensus (consensus tracking) problem of multi-agent systems (MAS) with event-triggered communication. A novel hybrid eventtriggering mechanism is proposed to reduce the burden of network transmission, and it is ensured that Zeno behavior does not occur. Besides, it is required that the control protocol is only updated at agent’s own triggering instant. Compared with the existing works, the main contribution is that the minimum inter-event time (MIET) can be pre-specified, which is important for physical implementation, and the control update frequency is also reduced. An example is given to verify the correctness of the proposed hybrid event-triggered control strategy.

Microbial fuel cells are one of the most important elements in the renewable energy supply chain. To increase the efficiency and performance of the fuel cell, designing a suitable control method is essential to achieve reliable performance and output stability. By considering the parametric uncertainties on the microbial fuel cell model as well as nonlinear terms, this paper presents a novel finite time adaptive sliding mode control method that achieves optimal performance of fuel cell in a finite time and also ensures the stability of the closed loop system. Sliding mode method without linearization or elimination of nonlinear terms has been used as a robust method to overcome uncertainty effects and guarantees proper operation of the fuel cell in the presence of the effects. The finite time convergence of the states is also assured by using of the proposed method. Furthermore, it uses an adaptive method to determine the sliding mode control coefficients which eliminates the necessity to know the upper bound of uncertainty. Finally, the simulation results show the efficiency and stability of the proposed method in different operating conditions.

In this paper, a novel active control approach is designed for surge instability in the compressor system using the finite-time fuzzy sliding mode scheme. The primary novelty of this study lies in the development of a finite-time fuzzy sliding mode control for the surge instability in a compressor system in the presence of disturbance and uncertainty in the characteristic curve of the compressor and also throttle valve. To ensure the stability of the closed-loop system in Lyapunov's concept, a finite time active control method is proposed based on fuzzy estimation method and robust adaptive and sliding mode methods. Achieving finite time stability and rapid elimination of deep surge instability occurs through a fast sliding mode design, while fuzzy and adaptive techniques are used to estimate uncertainty and nonlinear terms, as well as to obtain optimal estimation weights. The simulation results in MATLAB environment and comparison show that the suggested method provides better quality control in terms of surge suppression, robustness, and overcoming uncertainty and disturbance effects.

The power generation subsystem represents one of the principal components of a space system and is usually assembled from solar arrays and PPT topology. This paper aims to design and implement an algorithm to continuously extract the maximum power from the solar cells and deliver it to the consumer with minimum loss. In this regard, a brief introduction to the various parts of the power generation subsystem is provided and through accurate modeling of the solar cell and exploring the contributing factors to its power generation (including temperature, radiation, and space radiation), the algorithm is proposed based on the impedance matching concept. Simulation studies using MATLAB software have estimated an approximate 0.25065W per square centimeter power extraction and delivery to the customer. Our results suggest that the proposed approach can reduce steady-state losses while ensuring accuracy.

This paper investigates the event-triggered consensus problem of multi-agent systems with uncertainties and input saturation. First, a fully distributed robust consensus low-gain feedback control strategy is proposed, in which some global information, such as the communication graph and the scale of network, is not needed. Then, by defining an internal dynamic variable to memory the past state, an adaptive dynamic event-triggering mechanism is proposed, which contributes to reducing the usage of communication resources and also does not rely on any global information. Furthermore, Lyapunov-based consensus analysis results are presented, and it is also formally shown that Zeno behavior can be excluded with the proposed consensus protocols. Finally, a numerical example is provided to illustrate the effectiveness of the proposed results.

In this paper, a novel control approach is designed for surge instability in the compressor system using the finite-time adaptive sliding mode scheme. The primary novelty of this study lies in the development of a finite-time adaptive control for the surge instability avoidance in a compressor system in the presence of disturbance and uncertainty in the characteristic curve of the compressor and also throttle valve. The Lyapunov method is utilized to verify the finite-time stability of the closed-loop system. The performance of the presented method is compared against other methods in the literature through simulations in Matlab. The results suggest that our designed controller outperforms the existing ones in terms of surge avoidance and robustness against uncertainties and disturbances.

Model-based control strategies for microbial fuel cell are able to create a balance between fuel supply, mass, charge and electric charge, performance efficiency. This paper designs a new adaptive sliding mode control scheme of single chamber single population microbial fuel cell. The adaptive method estimates parametric uncertainty and nonlinear terms while the sliding mode method achieves microbial fuel cell performance targets. The significant advantage of the suggested scheme is its capability to provide robustness against parametric uncertainties and handle systems nonlinearity. The Lyapunov technique has been used to demonstrate robust stability in the face of nonlinearity and uncertainty. Numerical simulations confirms that the proposed control method is able to meet the desired specification in the presence of varieties of parametric uncertainty.

This paper studies the event-triggered consensus problem of multi-agent system with general linear dynamics. A novel dynamic event-triggered strategy is proposed, and it is formally shown that the proposed dynamic event-triggered strategy can achieve larger triggering intervals than the existing ones. Then, a state observer and a disturbance observer based on the local state information are developed. By using the observers' states at event time instants, a distributed control protocol is proposed to reject the disturbances. Based on the proposed dynamic event-triggered strategy and control protocol, Lyapunov-based analysis is provided to show that the consensus can be achieved. In addition, by adding an exponential term into the triggering condition, Zeno behavior can be ensured to be excluded. Finally, the effectiveness of the proposed methods is illustrated by a numerical example.

Fu, X.; Xu, X., and Wang, K., 2020. Design of an intelligent marine ship lighting power detection system based on Internet of things. In: Yang, D.F. and Wang, H. (eds.), Recent Advances in Marine Geology and Environmental Oceanography. Journal of Coastal Research, Special Issue No. 108, pp. 144–150. Coconut Creek (Florida), ISSN 0749-0208.The marine ship lighting system is a significant unit of navigation to improve the safety of the crew. The traditional oceangoing voyage lighting power system has low efficiency, delays in troubleshooting times, and high energy consumption in the detection of fault points. Based on the Internet of Things (IoT) and automation, the authors proposed an intelligent lighting power detection method to ensure the safe, efficient, and stable operation of the oceangoing voyage. Specifically, in the distinct lighting and dynamic circuit multifault environment of the oceangoing voyage, the illumination detection time limit of a traditional lighting power system and the proposed intelligent lighting system were compared; the current and voltage values of the intelligent lighting system were measured and analyzed. This method proved to be effective in detecting a variety of faults of an oceangoing voyage lighting system and has fast and stable performance as well as high accuracy. Therefore, the proposed method can effectively avoid unexpected accidents caused by power lighting failures and improve the green energy-saving performance of oceangoing voyage lighting systems.

This paper investigates the distributed event-triggered consensus control problem for multi-agent uncertain systems with input saturation. Frist, a fully distributed low gain feedback control strategy is proposed for each agent. It is shown that under this control strategy, we do not rely on any global information of the network graph and network’s scale. The proposed control law is then extended with a dynamic event-triggered mechanism, which removes the requirement for continuous communications. Under the event-triggered control law, we proved that each agent strictly excludes Zeno behavior. Finally, a numerical example is given to illustrate the effectiveness of the proposed control strategy.

An approach to the design of filling system of beverage machine based on AT89C51 microcontroller is explicitly elaborated in this paper. The filling system of beverage machine uses the way of quota of the liquid weight to actualize the liquid filling, and the design includes two parts, one is hardware circuit and the other is programs. This system performs stable. In addition, the cost of design and manufacture is lower, so it is easy to make promote and popularize widely.

The indoor temperature and humidity detection system based on STC15F2K60S2 is designed in this paper. The temperature and humidity sensor DHT22 to monitor the indoor temperature and humidity are used, and the temperature and humidity data to the user’s handheld device are wirelessly transmitted, when the temperature reaches or exceeds the user set the temperature alarm value, and the system sound and light alarm, to remind the user.

The steer-by-wire system, with which the conventional mechanical linkage between the steering wheel and the front wheel is removed, is suited to active steering control, to improve vehicle stability, dynamics and maneuverability, as well as to autonomous steering control to assist the driver. Conventional controller for steer-by-wire system is designed with general feedback control method. However, driver can not exactly feel reaction torque generated from tire. This paper adopts the method of integral partition PID Control. Computer models were developed under the environment of MATLAB/SIMULNK and the Integral Partition PID Control scheme of steer-by-wire control was presented too. Return-to-center of steering wheel and steering of the front wheel were simulated and analyzed. The simulation results illustrate that steer-by-wire controller with Integral Partition PID Control is better in dynamic characteristics than the conventional PID controller in the return-to-center of steering wheel and stabilization time.

The PID control of RBF-NN is taken for the nonlinear system. Due to the low quality of clustering in the clustering algorithm of the traditional RBF-NN, the rate of convergence is directly influenced by the initial value. In this paper, the quality of the clustering has been raised and the initial value has been optimized through the improvements of the clustering algorithm by taking the K-means-algorithm and the Ant Colony Optimization (ACO). The simulation results show that the rate of convergence is precise and fast after the clustering algorithm is improved and the PID control is better than the one without taking the new method.