ZigBee Network for AGV Communication in Industrial Environments

The knowledge of error nature in wireless channels is an essential constituent of efficient communication protocol design. To this end, this paper is the first comprehensive bit- and symbol-level analysis of IEEE 802.15.4 transmission errors in industrial environments. The intention with this paper is to extract the error properties relevant for future improvements of wireless communication reliability and coexistence of radio systems in these harsh conditions. An extensive set of bit-error traces was collected in a variety of scenarios and industrial environments, showing that error behavior is highly dependent on the cause of packet corruption. It is shown that errors inflicted by multipath fading and attenuation exhibit different properties than those imposed by IEEE 802.11 interference. The statistical behavior of these two patterns is concurrently investigated in terms of differences in bit-error distribution, error burst length, channel memory length, and the scale of packet corruption. With these conclusions at hand, abiding to the computational constraints of embedded sensors and the statistical properties of bit-errors, a Reed-Solomon $(15,k)$ block code is chosen to investigate the implications of bit-error nature on practical aspects of channel coding and interleaving. This paper is concluded by a number of findings of high practical relevance, concerning the optimal type, depth, and meaningfulness of interleaving.

Wireless communications in industrial environments are seriously affected by reliability and performance issues, due to the multipath nature of obstacles within such environments. In order to utilize wireless systems for M2M applications in industrial environments, it is necessary to investigate and model their channel characteristics for optimal design and reliability assessment. However, the wireless channel characterization in such environments has not been sufficiently addressed in the literature within the scope of our knowledge. In this paper, to shed light on the channel modeling for plant applications, we measure and analyze the indoor channel characteristics in a typical thermal power plant. Our results indicate that the channel characterization of the plant environment is specific when compared with the general environments such as home and office. The findings in this paper provide a useful guidance to the design of wireless system for the realization of reliable control systems in power plants.

SUMMARYWireless communications in industrial environments are seriously affected by reliability and performance issues, due to the multipath nature of obstacles within such environments. In order to utilize wireless systems for machine‐to‐machine applications in industrial environments, it is necessary to investigate and model their channel characteristics for optimal design and reliability assessment. However, the wireless channel characterization in such environments has not been sufficiently addressed in the literature within the scope of our knowledge. In this paper, to shed light on the channel modeling for plant applications, we measure and analyze the indoor channel characteristics in a typical thermal power plant. Our results indicate that the channel characterization of the plant environment is specific when compared with the general environments such as houses and offices. The findings in this paper provide a useful guidance to the design of wireless system for the realization of reliable control systems in power plants.

Trealize the Industry 4.0 vision and enable mobile connectivity and flexible deployment in harsh industrial environments, wireless communication is essential. But before wireless communications technology can be widely deployed for critical control applications, first it must be assessed, and that requires a comprehensive characterization of the wireless channel. This can be done by analyzing large amounts of wireless data collected from different industrial environments. In this article, we discuss the possibilities offered by a recently published industrial wireless data set. This data set is more exhaustive than measurements previously reported. We show two cases of how those data have been applied to improve latency performance and to investigate the feasibility of physical-layer security techniques for wireless communication in industrial environments.

In the Factory of the Future, wireless communication will play an important role. DECT, the European standard for digital cordless telecommunication is considered to be the prime means for realizing a wireless infrastructure for data communication in industrial environments. In this paper, the authors consider the following situation: when different owners of mobile communication equipment will be forced to communicate with each other on the factory floor, the task of interweaving their communication streams becomes difficult. In terms of telecommunications, the problem must be solved. Alas, DECT's support for roaming is only on a local basis, meaning a single domain or island. The authors propose the OSI X.500 Directory Service as a standard solution for DECT's mobility management. Its suitability for mobile management application needs not be verified, as this was already done by Hoff (1997). Instead, the prototype of an interworking unit is verified by use of simulations. Without roaming, the integration of DECT into the Factory of the Future will be limited to local Private Branch Exchange (PABX) functionality.

An on-chip 4to20mA reconfigurable current loop transmitter with four input channels for remote smart sensor applications is presented. The designed system includes: a like-HART protocol based on frequency-shift keying modulator (FSK) and demodulator to an efficient communication in industrial environment, a power management sub-system, a standard 4to20mA output and an embedded NVM memory (256 bytes) for calibration and identification purposes. The integrated circuit was fabricated in standard 0.6um CMOS technology occupying an área of 11.1mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> .

This work explores the secure data transmission approach to control a robotic arm using Li-Fi technology. Although Li-Fi offers built-in security by keeping the light within the walls of the environment, where it is used, leaks through windows are a concern. The proposed system addresses this concern by using a multi-mode approach with three options: without encryption, Rivest Cipher 4 (RC4) encryption, and Advanced Rivest Cipher 4 (ARC4) encryption. Users can choose the appropriate mode based on data sensitivity and processing constraints. The system transmits the movement commands to the robotic arm via a controller and transmitter. In used encryption modes, the received data is decrypted before instructing the robotic arm to perform the designated action. This secure Li-Fi system offers a promising solution for reliable and secure communication in industrial environments, addressing the limitations of traditional RF communication and improving data security.

Reliable optical fiber link for communications in industrial environments

In the challenging environment and Cutting-edge technology in mining industry, reliable and effective communication is a high-stake issue, along with the objectives of safe and efficient underground mining operations. Automation through remote and automatic systems has delivered improvements in workplace health and safety for employees, operational management, energy and cost-effectiveness, and real-time response to events. In this context, Wireless Sensor Networks (WSNs) have been widely employed in underground monitoring and communication systems for the purpose of environmental monitoring, the positioning of workers and equipment, operational monitoring and communication system. Considering the capabilities of WSNs, a ZigBee network is adopted in this study.

The consolidation of 5G technologies makes the Industry 4.0 establishment more feasible than ever. Network Function Virtualization (NFV) and Edge Computing aim at managing the multi-vendor industrial and network infrastructure and guaranteeing the high-performance requirements of industrial processes. Furthermore, industrial production workflows require the collaboration between robots, actuators and sensors in the factory floor. In this direction, Network Slicing allows the deployment of complex end-to-end network services, enabling the collaboration of industrial applications of different vendors and ensuring low latency, safety and optimal resource management. Extending the standard ETSI NFV reference architecture, this article proposes a deployment and orchestration mechanism for enabling Cross-Slice Communication (CSC) in industrial environments. For evaluation purposes, a Warehouse Robotics use case, which requires the collaboration of mobile robotic agents in an automated storage and retrieval system, is used. The experimental results show the significant improvements in the expected mission completion delay and transmission time when using the propounded CSC approach compared to other inter-communication methods.

The objective of this work is to provide decision-making processes with an updated/real picture of the mobile resources in industrial environments through a constant feedback of information. The combination of identification technologies and wireless sensor networks (WSN) is proposed as a key development to guarantee an accurate and timely supply of online information regarding the localization and tracking of the mobile wireless devices. This approach uses a cooperative and distributed localization system, called ZigID, which is a WSN based on a Zigbee network with radio frequency identification (RFID) active tags as end nodes. The WSN can recover not only the ID information stored at the tags attached to mobile resources, but also any other useful data captured by specific sensors for acceleration, temperature, humidity and fuel status. This paper also shows the development of ZigID, including devices and information flows, as well as its implementation in ground handling operations at the Ciudad Real Central Airport, Spain.

Challenging environments comprise a range of scenarios, which share the fact that it is extremely difficult to establish a communication link using conventional technology due to many impairments typically associated with the propagation medium and increased signal scattering. Specifically, underwater and underground media are known to absorb electromagnetic radiation, which heavily affects the overall path loss. Industrial and disaster environments can be viewed as rich scattering environments with corresponding substantial multipath propagation leading to intersymbol interference and deterioration of signal quality. Although the challenges for the design of communication networks, and specifically the Internet of Things (IoT), in such environments are known, there is no common enabler or solution for all these applications. Reconfigurable intelligent surfaces (RISs) have been introduced to improve the signal propagation characteristics by focusing the signal power in the preferred direction, thus making the communication environment 'smart'. While the usual application of RIS is related to blockage avoidance, the very same technique can be used to reduce the effect of multipath and even partially compensate the signal absorption via passive beamforming. Due to the beneficial properties of RIS, its use in challenging environments can become the aforementioned enabler and a game changing technology. In this paper, we discuss potential use cases, deployment strategies and design aspects for RIS devices in underwater IoT, underground IoT as well as Industry 4.0 and emergency networks. Furthermore, we provide a potential hardware architecture and derive the expected signal quality. The numerical results reveal substantial performance gains of up to 20 dB per decade. In addition, novel research challenges to be addressed in this context are described.

A CASE TOOL FOR MODELING AND SIMULATING DISTRIBUTED CONTROL SYSTEMS BASED ON MMS

This paper describes a data acquisition system developed to solute the problem of different data acquisition modules communication in ubiquitous industrial environment. The system can allow faster reconfiguration of plant-floor networks as applications change. It can achieve higher throughput, lower average message delay and less average message dropping rate in wireless communication. The development of a data acquisition system for rotogravure printing press in ubiquitous industrial environment also is reported. It illustrates that the system can perform well in industrial application.

Recent years have witnessed rapid adoption of low-power Wireless Sensor-Actuator Networks (WSANs) in process industries. To meet the critical demand for reliable and real-time communication in harsh industrial environments, the industrial WSAN standards, such as WirelessHART, ISA100, WIA-FA, and 6TiSCH, make a set of specific design choices, such as employing the Time Slotted Channel Hopping (TSCH) technique. Such design choices distinguish industrial WSANs from traditional Wireless Sensor Networks (WSNs), which were designed for best-effort services. Recently, there has been increasing interest in developing new methods to enable autonomous transmission scheduling for industrial WSANs that run TSCH and the Routing Protocol for Low-Power and Lossy Networks (RPL). Our study shows that the current approaches fail to consider the traffic loads of different devices when assigning time slots and channels, which significantly compromises network performance when facing high data rates. In this paper, we introduce ATRIA, a novel Autonomous Traffic-Aware transmission scheduling method for industrial WSANs. The device that runs ATRIA can detect its traffic load based on its local routing information and then schedule its transmissions accordingly without the need to exchange information with neighboring devices. Experimental results show that ATRIA provides significantly higher end-to-end network reliability and lower end-to-end latency without introducing additional overhead compared with a state-of-the-art baseline.