Industry 4.0 glossary.

Industry 4.0

Fourth industrial revolution · FR: industrie 4.0

Industry 4.0 is the name for connecting machines, systems and people in manufacturing so that production data flows between them and decisions are taken on it. The term came from a German government programme and is now used broadly for digitised manufacturing.

It names a direction rather than a product, so it is defined in practice by what a plant actually connects: machines to an MES, the MES to the ERP, maintenance to production. Most of the value comes from the unglamorous part, reliable data from every machine, before anything that needs a new acronym.

Smart factory

Connected factory · FR: usine connectée

A smart factory is a plant where equipment and systems share data continuously, so the state of production is known as it happens and can be acted on without waiting for a report.

The word suggests autonomy, but in most plants it means something more modest and more useful: every machine’s state is recorded automatically, every stop has a reason, and the people who can act see it in time to do so. A factory gets smarter one line at a time, not in one project.

Cyber-physical system

CPS · FR: système cyber-physique

A cyber-physical system is equipment in which physical processes and software are tightly linked: sensors measure, software decides and actuators act, in a loop. A machine with its controller and its network connection is one.

Most industrial equipment has been cyber-physical since programmable controllers appeared. What Industry 4.0 adds is the link outward, from the machine’s own loop to the systems above it, which is also what makes network security part of maintaining the equipment.

Digital twin

FR: jumeau numérique

A digital twin is a software model of a physical asset, line or process, kept in step with the real one by data from it, and used to monitor, simulate or optimise it. The model can range from a 3D simulation to a set of live values and rules.

The term covers very different things, so the useful question is what the model is used for and how current it is. A simulation used once to design a line and a live model fed from the controllers are both called twins; only the second needs a reliable data connection to every machine it represents.

Digital thread

FR: fil numérique

The digital thread is the connected record of a product across its life: design, planning, production, quality, delivery and service, linked so that any point can be traced to the others.

On the factory floor its part is the execution record: which order, which machine, which materials and which checks. It breaks wherever data is re-keyed between systems, so in practice it is built by removing manual hand-offs one at a time.

IT/OT convergence

Information technology and operational technology

IT/OT convergence is the joining of information technology, the business systems and networks, with operational technology, the controllers and systems that run physical equipment. It is what lets plant-floor data reach business systems directly.

The two sides have different priorities: IT patches and updates, OT keeps a running line running and changes nothing that works. Projects succeed when the boundary is designed rather than dissolved, with defined points where data crosses and clear ownership on each side.

Vertical integration

FR: intégration verticale

Vertical integration connects the levels of a plant’s systems, from sensors and controllers up through supervision and the MES to the ERP, so that information passes between them without being re-entered.

ISA-95 describes the levels and what each exchanges. The two hardest seams are usually machine to MES, because of the variety of controllers, and MES to ERP, because the two hold the same order at different grains.

Horizontal integration

FR: intégration horizontale

Horizontal integration connects systems at the same level across a value chain: production steps with each other, one plant with another, a plant with its suppliers and customers.

Inside a plant it means one line’s output becoming the next one’s input in the record, not just on the floor. Across companies it usually means agreed formats for orders, shipments and quality data, which is more a matter of contracts than of technology.

ERP

Enterprise Resource Planning · FR: PGI

Enterprise Resource Planning software runs the business side of a company: orders, purchasing, inventory, planning, costing and accounting, in one system of record.

It plans what to make and settles what was made, at the grain of the order or the shift. It is not built to record what each machine did minute by minute, which is why plants that need that detail add an MES beneath it. The MES vs ERP comparison sets out the boundary.

Real-time production monitoring

FR: suivi de production en temps réel

Real-time production monitoring shows the state and output of equipment as production runs, from data read automatically, rather than in a report after the shift.

Its value depends on who sees it and what they can do: a figure on a screen in the office changes nothing on the line by itself. It is most useful when it reaches the people who can act within the shift, with the reason for each stop recorded while it is still fresh.

Paperless shop floor

FR: atelier sans papier

A paperless shop floor replaces paper instructions, checklists, forms and logs on the production floor with electronic ones, completed at terminals and stored with the production record.

The gain is less the paper than the delay and the transcription: a check recorded on paper reaches a system hours later, if at all. The risk is a form that is slower to fill in than the paper it replaced, so the screens have to be designed around the task rather than around the database.

Lean manufacturing

Lean · FR: lean manufacturing

Lean manufacturing is a way of running production that focuses on delivering what the customer values with the least waste of time, material and effort. It grew out of the Toyota Production System.

It names seven classic wastes: overproduction, waiting, transport, over-processing, inventory, motion and defects. Its tools, from takt time to SMED, predate digital systems, and a data system supports lean when it makes waste visible faster, not when it becomes another process to feed.

Kaizen

Continuous improvement · FR: amélioration continue

Kaizen is the practice of continuous, incremental improvement, carried out by the people who do the work. The word is Japanese for change for the better.

It runs either as an everyday habit or as a focused event on one problem over a few days. Either way it needs a baseline: improvement that cannot be measured against what was there before is hard to keep, and the team that made it rarely gets the credit.

PDCA

Plan, do, check, act · FR: roue de Deming

PDCA is a four-step improvement cycle: plan a change, do it on a small scale, check the result against what was expected, and act by adopting, adjusting or abandoning it. It is associated with W. Edwards Deming.

The step most often skipped is check, because it needs data from before and after the change, collected the same way. Without it the cycle becomes plan and do, repeated, and the plant cannot tell which of its changes worked.

Gemba

FR: gemba, terrain

Gemba is the place where the work is done, on a plant the production floor. A gemba walk is a manager going there to observe the work directly rather than through reports.

Its point is that reports summarise and the floor does not: the cause of a stop is often visible on the line and absent from the data. Data and the walk support each other, the data showing where to look and the walk showing what the data missed.