Communications needs in manufacturing plants

Planning for communications needs in industrial environments starts with the network’s first layer.

A composite cable comprises optical fibers for data and copper wires to deliver remote power. In an industrial environmental, composite cable can be used in a network of millimeter-wave 5G radios supporting a coverage zone.
A composite cable comprises optical fibers for data and copper wires to deliver remote power. In an industrial environmental, composite cable can be used in a network of millimeter-wave 5G radios supporting a coverage zone.
Corning

By Art King,

Manufacturing plants and operations are each unique in their own way. In this article, we will discuss many of the communications opportunities that can equip new and existing buildings with more agile, resilient, and intelligent digital infrastructure. Manufacturing system architects are leveraging wired, wireless, and optical transport supporting robots, machine vision, production line machines, product transport, sensor arrays, programmable logic controllers (PLCs), and distributed Internet of Things (with future artificial intelligence management overlays) to increase process intelligence, agility, safety, and reduce defects and operational expenses.

Communications technology is the underlying foundation for manufacturing and producing goods of all types. The availability of many communications mediums and a vast array of sensors and controls that fit a wide variety of applications enables architects to think about effectively monitoring and managing more of the environment than ever before. In addition, most of the production subsystems feature application programming interfaces (APIs) and software that enable them to be integrated into an end-to-end framework.

Planning for communications needs starts with the first layer of the foundation—the wired and wireless data. Options and usage scenarios include the following.

Wired infrastructure

LAN—The Ethernet LAN is a well-known workhorse technology in service since the 1990s. The most common implementations feature a 1-Gbit/sec data rate over Category 5e or Category 6 twisted-pair cable plant.

Usage example: Industrial control computers for production equipment will have an Ethernet port that is connected to the plant network via an Ethernet switch supporting the local wiring zone.

Coaxial cables—In original machine-vision applications, older analog cameras networked to frame grabbers using 75-ohm coaxial cable. CoaXPress, a newer standard for digital machine vision that can leverage coaxial cable plant, has been developed to deliver up to 12.5 Gbits/sec.

Usage example: Machine vision on high-speed inspection lines.

Fiber-optic cabling—Fiber-optic cabling is used to achieve Ethernet LAN data rates of 10, 40, and 100 Gbits/sec. Future manufacturing systems will achieve these data rates on their own or, in a shared application, a single 5G radio may aggregate many traffic flows to these data rates. Fiber-optic cable offers an additional benefit in manufacturing in that it is immune to electromagnetic interference (EMI). EMI is essentially electrical “noise” transmitted by copper wires that overwhelms the legitimate communications signals on the wires. In manufacturing, heavy equipment may generate continuous EMI from spinning motors or large transient electrical spikes from stepping motors or welders.

Usage example: Millimeter-wave 5G radio supporting a coverage zone (cell) inside a plant. Nearby machines have a 5G interface and are attached to the 5G cell. The fiber-optic cabling used in this application is a “composite cable” that consists of optical fibers to carry data flows and copper wires to deliver remote power to the mmWave 5G radio. Additionally, a harsh manufacturing environment might require the cable to be protected from mechanical exposure or damage from chemicals or heat. In those situations, armored composite cable could be used instead of building out conduits.

Usage example: Production machine with a 10-Gbit/sec interface. Because the machine already has its own onboard power, the fiber-optic cabling does not require additional copper wires. Again, armored fiber-optic cabling could be used instead of building out conduits.

Wireless infrastructure

WiFi—Emerging in the mid-2000s, this is the workhorse of enterprise wireless with the contemporary platform architecture of “thin access points” (AP) paired with a controller(s). The latest generation is 802.11ax and the industry is in a transition from earlier versions. The status of WiFi in manufacturing is mature in that systems that were suited to migrate to use WiFi as a data transport are already using it. Where tightly controlled and predictable bidirectional communications are required or where distance is an issue, most system architects prefer Ethernet cable to WiFi. The transport to connect the WiFi AP to the network is usually a type of Power over Ethernet (PoE) over a Category 5e or Category 6 cable.

Usage example: Remote access to computer numerical control (CNC) machines like a lathe or horizontal mill (that is close enough to an AP) where remote access is used to upload programs and monitor the health of the system.

LTE—With the launch of Citizens Broadband Radio Service (CBRS) on September 18, 2019, LTE became an accessible technology for organizations that do not own wireless spectrum (i.e. not a mobile operator). In the CBRS spectrum band, the wireless infrastructure that is installed in a site requests spectrum for its radios from a cloud service called a spectrum access service (SAS). This is a breakthrough as it allows any company that requires the controlled and predictable access characteristics of LTE to deploy it to support the manufacturing process. LTE is desirable because it provides fair and predictable access to all attached devices, quality service controls to enable priority access for critical traffic, and a signal reach far beyond that of WiFi. The transport to connect an LTE radio to the network is usually a type of PoE over a Category 5e or Category 6 cable.

Usage example: Outdoor access to a solar-powered pressure sensor attached to petrochemical feeder line within a refinery—the sensor has priority access as a rise in pressure must trigger a set of time-sensitive actions across the refinery. The pressure sensor is needed for a refinery process efficiency improvement, but the cost of the conduit and power to the installation location drives up the costs in the business case. Adding CBRS as a shared medium to blanket the geographic area of the refinery in signal enables private LTE attached sensors, infrared cameras, mobile devices with control apps onboard, and other innovations to be deployed cost-effectively.

5G—The next generation of infrastructure for mobile operators around the globe, 5G has many additional technology features that will be attractive to the manufacturing community, including the following.

  • Wideband channels in higher frequency ranges that enable attached devices to run 20x faster than LTE.
  • Ultra-reliable low-latency computing (URLLC) enabled by edge computing in the network along with prioritization network controls. The goal is that for time-sensitive functions that require fast responses, pieces of applications are moved to the edge computing platform, so they can respond on behalf of the cloud service. This URLLC function eliminates the round-trip delay from edge of network to cloud service that is beyond the time boundary allowed to the 5G attached device.
  • Network slicing is a method to allocate the network by chopping it into slices with four main controlling factors (core network to use, priority level, bandwidth required, maximum round-trip time).
  • Beam-forming antenna technology that, for every transmission to a mobile device, knows the location of the device and points the energy at that location while transmitting.
  • The transport to connect a 5G radio to the network will be composite fiber-optic.

Usage examples: As more production systems have machine vision and large KPI/metrics flows that feed a controlling AI engine, some activities will run on high-performance slices with wideband channels to continuously manage and adapt the production line. And, where 5G is supporting employee-attached mobile devices, the slice profile will be no more than today’s LTE.

The present and future communication needs in manufacturing are bigger and faster—like everything else around us. When LTE and 5G are involved, these platforms will require a companion logical implementation design developed and implemented with the customer. The key question is: Do engineers do this design work, or will this all be software-driven by a “wizard” front end?

Art King is director of enterprise services and technologies, wireless, for Corning Optical Communications.        

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