Redundancy and Diversity in Wireless Networks to Support Mobile Industrial Applications in Industry 4.0

Abstract

Factories are evolving into fully digitalized and networked structures for more adaptive and agile production ecosystems in the context of the Industry 4.0. Wireless communications will be a technical pillar of this evolution as it improves the reconfigurability of factories and the integration of mobile robots and objects. The integration of industrial wireless networks into the Industry 4.0 requires solutions capable to support highly reliable and deterministic low latency communications. This is particularly challenging for mobile industrial applications with constantly changing link quality conditions. This study experimentally evaluates for the first time the capacity of diversity and redundancy to improve the reliability and latency of wireless networks for mobile industrial applications. To this aim, a prototype is built in a collaborative robotics experimental facility. The prototype wirelessly connects a dual-arm robot and a mobile robot that collects and supplies components to the dual-arm robot. The prototype implements redundancy and diversity (using multipath TCP) for the wireless connections between both robots. The conducted trials show that both techniques improve the reliability of mobile industrial wireless communications even under the presence of interference. However, redundancy achieves lower latency levels and represents then the most attractive solution to support mobile industrial applications.

Analysis of NOMA-Based Retransmission Schemes for Factory Automation Applications

“…Specifically, the tests evaluated the use of two, three and four transmitters and they showed a non-linear behavior of the reliability increase while increasing the number of transmitters. Recently, in [18], the performance of spatial diversity with multiple redundant transmitters for mobile industrial communications is experimentally evaluated in a testbed with mobile robots. Authors implemented diversity using the Multipath TCP (MPTCP) protocol, which allows establishing different TCP connections between a transmitter and a receiver using multiple disjoint paths.…”

Reformist Framework for Improving Human Security for Mobile Robots in Industry 4.0

“…Our job is to provide an intelligence service to the Mobile Robot to establish the connection between the machines. Figure 1 represents Current Application Industry 4.0 [3]. In this regard, we offer a direction-finding design based on integrated control, which monitors robotic navigation and establishes the connection between the machines [4].…”

A Hybrid Reliable Routing Algorithm Based on LQI and PRR in Industrial Wireless Networks

“…In order to ensure that the information is not affected by background interference, path loss, multipath fading, and node failure in the transmission process, a variety of reliability enhancement techniques are proposed when discussing the challenges of wireless network security and reliability [3]. Redundancy is a way to improve reliability [4], which can be implemented on different layers and appear in the form of redundant packet content and error correction code (physical layer), repeated transmission (MAC layer), installing relay, or concurrent transmission with multiple paths. Hong et al proposed an object-oriented routing algorithm to realize multipath diversity for a time-invariant network environment [5].…”

“…Hong et al proposed an object-oriented routing algorithm to realize multipath diversity for a time-invariant network environment [5]. Although the above method [2][3][4][5] can improve the transmission reliability of IWNs, the cost is to consume more energy. The signal of the wireless communication node is sent out from the transmitting end, and it has experienced large-scale fading and small-scale fading [6].…”