Redundancy and Diversity in Wireless Networks to Support Mobile Industrial Applications in Industry 4.0
M. C. Lucas-Estań, B. Coll-Perales J. Gozalvez
IEEE Transactions on Industrial Informatics  (January 2021)
 ISSN:1551-3203  DOI:10.1109/TII.2020.2979759  - vol. 17, no. 1, pp. 311-320


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 article 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.