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This paper aims to analyze the key factors influencing the synchronization performance of distributed motion control system and to improve the synchronization performance for peripherals control of this system.

This paper deals with the software synchronization problems of distributed motion control system based on real-time Ethernet. First, combined with communication and control tasks, the key factors affecting synchronization performance of system are analyzed. Then, aiming at key factors and considering the synchronization of system bus, protocol conversion and task scheduling, a software synchronization method based on CANopen protocol and real-time Ethernet is proposed. Finally, the feasibility of this method is verified by establishing distributed motion control system and testing the synchronization performance of terminal control signals of slaves.

Based on this method, the results show that the synchronization accuracy for peripherals control of all slaves could be about 100 ns.

This research provides high-precision synchronization method, which could lay a foundation for the application of distributed motion control system in the field of assembly automation, such as multi-axis assembly robots control.

In distributed motion control system, many factors affect the synchronization performance. At present, there is no synchronization method that could comprehensively consider these factors. This paper not only analyzes the key factors influencing the synchronization performance of system but also proposes a synchronization method. Therefore, the method proposed in this paper has certain theoretical value and engineering significance.

As the strategy of 5G new infrastructure is deployed and advanced, 5G-R becomes the primary technical system for future mobile communication of China’s railway. V2V communication is also an important application scenario of 5G communication systems on high-speed railways, so time synchronization between vehicles is critical for train control systems to be real-time and safe. How to improve the time synchronization performance in V2V communication is crucial to ensure the operational safety and efficiency of high-speed railways.

This paper proposed a time synchronization method based on model predictive control (MPC) for V2V communication. Firstly, a synchronous clock for V2V communication was modeled based on the fifth generation mobile communication-railway (5G-R) system. Secondly, an observation equation was introduced according to the phase and frequency offsets between synchronous clocks of two adjacent vehicles to construct an MPC-based space model of clock states of the adjacent vehicles. Finally, the optimal clock offset was solved through multistep prediction, rolling optimization and other control methods, and time synchronization in different V2V communication scenarios based on the 5G-R system was realized through negative feedback correction.

The results of simulation tests conducted with and without a repeater, respectively, show that the proposed method can realize time synchronization of V2V communication in both scenarios. Compared with other methods, the proposed method has faster convergence speed and higher synchronization precision regardless of whether there is a repeater or not.

This paper proposed an MPC-based time synchronization method for V2V communication under 5G-R. Through the construction of MPC controllers for clocks of adjacent vehicles, time synchronization was realized for V2V communication under 5G-R by using control means such as multistep prediction, rolling optimization, and feedback correction. In view of the problems of low synchronization precision and slow convergence speed caused by packet loss with existing synchronization methods, the observer equation was introduced to estimate the clock state of the adjacent vehicles in case of packet loss, which reduces the impact of clock error caused by packet loss in the synchronization process and improves the synchronization precision of V2V communication. The research results provide some theoretical references for V2V synchronous wireless communication under 5G-R technology.

The aim of this paper is to provide an update on the status of current fieldbuses and high‐speed Ethernet technologies for industrial automation.

The paper provides information on the various fieldbus technologies for industrial automation connectivity and examines high‐speed deterministic Ethernets for automated manufacturing and assembly plant.

The paper finds that the standards issue has still not been fully resolved, that Ethernets reduce manufacturing costs compared with conventional fieldbuses, that most effort has gone into making Ethernets work deterministically, rather than concentrating on IT and enterprise resource planning (ERP) integration, and that the internet will increasingly feed real‐time data to ERP levels.

The paper provides information on recent developments in Ethernet technologies.

The aim of this study was to develop a new generation of automatic systems based on cutting-edge design and practical welding physics to minimize downtime caused by defects and machine faults on the barges. Automatic welding has been used frequently on offshore pipeline projects.

An automated welding robot system for sub-sea pipeline installation was constructed. The system utilized the double-car double-torch welding, which is light-weight and compact, suited for offshore applications. Several state-of-the-art technologies were integrated into the control system design, including a heterogeneous network based on EtherCAT technology, network communications based on CANopen, motor synchronization, all-position welding, etc. In addition, the utilization of the CAN bus reduced the number of cable lines and increased the extensibility of the proposed welding robot system. An internal clamp with copper shoes assured a nice root weld and narrow bevel design and the welding efficiency was improved accordingly.

The trial was carried out to verify the rationality and effectiveness of the proposed automated system. The deposition rate of the backing welding could reach 17.78 kg/h; the average time for each welding was 340 s. This system was unique in that it features a dual-torch welding head that allowed for the deposition of one run with twice as much material as a single torch head. The experiment showed that the double-vehicle double-torch mode can greatly improve the welding efficiency of pipeline installation during the welding process.

The automated welding robot system will be applied to offshore pipeline projects.

This robot is the first submarine pipeline installation welding robot to use a heterogeneous network based on EtherCAT technology. Various aspects of the submarine pipeline installation welding robot’s design and performance were discussed, including mechanical body design, control system design and welding process specification.

Many synchronization approaches are based on low-level time capturing, causing a tight integration with the Media Access Control (MAC) layer. Alternatively, this study aims to present a hybrid approach combining both receiver–receiver and sender–receiver schemes to reduce the variation of two-way message exchange durations, in heavy-load networks. To achieve network-wide synchronization, a variant of Prim’s algorithm (Cormen et al., 2009) is used to build a spanning tree, guaranteeing the minimum number of ancestors and limited error propagation. The simulation results show that the proposed approach is very competitive with a set of the most-cited synchronization protocols. In addition, a new synchronization simulator SynSim was developed using C++ language

To achieve network-wide synchronization, a variant of Prim's algorithm (Cormen et al., 2009) is used to build a spanning tree, guaranteeing the minimum number of ancestors and limited error propagation.

Simulation results show that the proposed approach is very competitive with a set of the most-cited synchronization protocols. In addition, a new synchronization simulator SynSim was developed using in C++ language.

It can be concluded from the experiments that MDSP is suitable for WSNs especially if MAC layer timestamping is not possible. So, the mean delays synchronization protocol (MSDP) is suitable to achieve time synchronization in single-hop and multi-hop networks without the MAC layer timestamping in large wireless sensor network (WSN) deployments.

A future enhancement of MDSP could be switching between the traditional timestamping and the new proposed timestamping based on a given threshold, which is the number of nodes in the neighborhood and the load of the network. It will be also interesting to test it in a prototype. The proposed solution can be used in practice to implement the Time-division multiple access (TDMA) protocol in a WSN. In addition, the proposed simulator can be used in a computer network synchronization protocols course.

To the best of authors’ knowledge, this study’s contribution is original. In addition, the authors implemented a new synchronization simulator

With the development of integrated circuit and communication technology, digital secure communication has become a research hotspot. This paper aims to design a five-dimensional fractional-order chaotic secure communication circuit with sliding mode synchronous based on microcontroller (MCU).

First, a five-dimensional fractional-order chaotic system for encryption is constructed. The approximate numerical solution of fractional-order chaotic system is calculated by Adomian decomposition method, and the phase diagram is obtained. Then, combined with the complexity and 0–1 test algorithm, the parameters of fractional-order chaotic system for encryption are selected. In addition, a sliding mode controller based on the new reaching law is constructed, and its stability is proved. The chaotic system can be synchronized in a short time by using sliding mode control synchronization.

The electronic circuit is implemented to verify the feasibility and effectiveness of the designed scheme.

It is feasible to realize fractional-order chaotic secure communication using MCU, and further reducing the synchronization error is the focus of future work.

The purpose of this research is to compare an industrial ethernet based network (PROFINET Class 1) with a traditional fieldbus network (PROFIBUS).

Two sets of identical motors were used in the experimental set-up. The speed synchronisation of a lead and follower motors was compared using both PROFINET Class 1 and a PROFIBUS DP network. The level of synchronising achievable was used as a measure of performance for each network.

It was found that PROFIBUS DP produces a better performance for set point and load changes than PROFINET Class 1 network.

PROFINET Class 2 and higher could not be used in the experiment due to availability of equipment and funding.

This research provides a comparative study of two very popular industrial networks. The results can be used as reference by industry for selection of industrial networks.

The paper provides a manufacturer independent practical comparison of two industrial networks. The application area of speed synchronisation is demanding, and should inform the user on the performance and limitation of industrial networks.

This paper aims to study that for multi-agent systems, how to find proper control protocols to ensure synchronization when the input set of each agent is not the whole real axis but a discrete set, and how the coarseness of imprecise input sets affect the synchronization control of the multi-agent systems.

The paper uses a relative state feedback method and non-linear mapping functions to design a proper control protocol which matches the coarseness of the input set and ensures synchronization. For theoretical analysis, the paper uses an error analysis method and mathematic induction to prove the effectiveness of the designed control protocol. The paper also uses a numerical example to show the correctness of the theoretical results.

The paper provides a method for protocol design when the input set of each agent is imprecise. The paper establishes a bi-direction relationship which suffices for synchronization between the coarseness of the input set and the synchronization precision, and finds that this relationship describes how the coarseness of the input set affects the synchronization control of the multi-agent system.

This paper only studies the case with logarithmically distributed and uniformly distributed discrete input sets. The authors are encouraged to study the synchronization control of multi-agent systems under input sets with more general distributions.

The paper includes implications for coordination control of multi-agent networks when the actuator of each agent is with a limited capacity, which leads to the case of discrete input sets with limit precision.

This paper fulfils an identified need to study how the coarseness of the input set of each agent affects the synchronization control of the whole multi-agent system.

The purpose of this paper, is to solve the problem of finite-time fault-tolerant attitude synchronization and tracking control of multiple rigid bodies in presence of model uncertainty, external disturbances, actuator faults and saturation. It is assumed that the rigid bodies in the formation may encounter loss of effectiveness and/or bias actuator faults.

For the purpose, adaptive terminal sliding mode control and neural network structure are used, and a new sliding surface is proposed to guarantee known finite-time convergence not only at the reaching phase but also on the sliding surface. The sliding surface is then modified using a proposed auxiliary system to maintain stability under actuator saturation.

Assuming that the communication topology between the rigid bodies is governed by an undirected connected graph and the upper bounds on the actuators’ faults, estimation error of model uncertainty and external disturbance are unknown, not only the attitudes of the rigid bodies in the formation are synchronized but also they track the time-varying attitude of a virtual leader. Using Lyapunov stability approach, finite-time stability of the proposed control algorithms demonstrated on the sliding phase as well as the reaching phase. The effectiveness of the proposed algorithm is also validated by simulation.

The proposed controller has the advantage that the need for any fault detection and diagnosis mechanism and the upper bounds information on estimation error and external disturbance is eliminated.

This paper uses a cognitive analytics management approach to analyze, understand and solve the problems facing the implementation of information systems and help management do the needed changes to enhance such a critical process; the emergency management system in the health industry is analyzed as a case study.

Cognitive analytics management (CAM) framework (Osman and Anouz, 2014) is used. Cognitive process: The right questions are asked to understand the behavior of every process and the flow of its corresponding data; critical data variables were identified, guidelines for identifying data sources were set. Analytics process: Techniques of data analytics were applied to the selected data sets, problems were identified in user–system interaction and in the system design. The analysis process helped the management in the management process to make right decisions for the right change.

Using the CAM framework, the analysis to the Lebanese Red Cross case study identified system user-behavior problems and also system design problems. It identified cases where distributed subsystems are vulnerable to time keeping errors and helped the management make knowledgeable decisions to overcome major obstacles by implementing several changes related to hardware design, software implementation, human resource training, operational and human-technology changes. CAM is a novel and feasible software engineering approach for handling system failures.

The paper uses CAM framework as an approach to overcome system failures and help management do the needed changes to enhance such a critical process. This work contributes to the software engineering literature by introducing CAM as a new agile methodology to be used when dealing with system failures. Furthermore, this study is an action research that validated the CAM theoretical framework in a health emergency context in Lebanon.