Taiichi Ohno and Lean Principles in Production

When Taiichi Ohno began developing what would become the Toyota Production System (TPS), Japan faced limited resources, low production volumes and constantly changing customer demand. Competing with the mass-production model adopted by American manufacturers was simply unrealistic.

Instead, Ohno developed a different approach: rather than maximizing production, manufacturers should maximize value while eliminating everything that failed to contribute to it.

His philosophy was built on direct observation.

One of his best-known teaching methods was the Ohno Circle. He would draw a chalk circle on the factory floor and ask managers to stand inside it for hours, simply observing the production line. Before proposing solutions, they first needed to understand how people, machines and processes actually interacted.

The lesson remains remarkably relevant today.

Whether developing an industrial HMI or optimizing an assembly process, meaningful improvements begin with understanding reality rather than making assumptions.

For Ohno, efficiency was never about working faster.

It was about removing everything that prevented value from reaching the customer.

He identified seven categories of waste, known collectively as muda:

• Overproduction
• Waiting
• Transportation
• Overprocessing
• Excess inventory
• Unnecessary motion
• Defects requiring rework

The Toyota Production System is built on two complementary principles.

Just-in-Time means producing only what is needed, when it is needed and in the quantity required. By aligning production with actual customer demand, manufacturers reduce unnecessary inventory, improve responsiveness and use resources more efficiently.

Jidoka, often translated as automation with a human touch, ensures that quality is built into the production process itself. Instead of allowing defects to move downstream, abnormalities are detected early so corrective action can be taken immediately.

Together, these two principles transformed manufacturing from a system focused on output into one focused on delivering value.

Industrial Human Machine Interfaces are rarely mass-produced consumer products.

Every project may combine different display technologies, projected capacitive or resistive touch systems, optical bonding, embedded electronics, ruggedized enclosures and application-specific software. This variety creates complexity throughout the manufacturing process.

Lean principles help manufacturers manage that complexity without sacrificing flexibility.

In practice, this means:

• Standardized workflows for display integration and optical bonding.
• Repeatable calibration of touch technologies.
• Functional testing throughout production rather than only at the end.
• Complete traceability across the manufacturing process.
• Visual management that allows abnormalities to be identified immediately.
• Production layouts that reduce unnecessary movement of materials and components.

The objective is not simply to manufacture faster.

It is to deliver consistent quality while remaining flexible enough to meet highly customized customer requirements.

Lean Manufacturing is often associated with cost reduction.

In reality, lower costs are the consequence of better processes rather than the primary objective.

The real goal is to design quality into every stage of production.

For manufacturers of industrial HMIs, whose products may operate in medical devices, industrial automation, transportation or other mission-critical environments, preventing defects is significantly more valuable than correcting them after assembly.

Jidoka reflects exactly this philosophy.

In practice, it means:

• Detecting abnormalities as early as possible.
• Stopping the process before defects propagate.
• Identifying root causes rather than treating symptoms.
• Continuously improving the process to prevent recurring issues.

Quality should never depend solely on final inspection.

It should be embedded throughout the entire manufacturing process.

Taiichi Ohno also believed that no process is ever truly finished.

Markets evolve.

Technologies change.

Customer expectations continue to grow.

For this reason, Lean embraces the philosophy of Kaizen, or continuous improvement.

Rather than relying on occasional major transformations, Kaizen encourages organizations to pursue small improvements every day.

These improvements may include:

• Simplifying an assembly procedure.
• Improving workstation ergonomics.
• Optimizing testing sequences.
• Refining production layouts.
• Making quality controls more effective.

Individually, each improvement may appear modest.

Together, they create substantial gains in efficiency, consistency and product quality.

Most importantly, Kaizen recognizes that the people closest to the production process are often those best positioned to improve it.

Today, Lean principles influence software development, healthcare, engineering and logistics as much as manufacturing.

The same mindset naturally applies to the development of industrial Human Machine Interfaces, shaping engineering decisions, production strategies, validation procedures and product evolution.

Taiichi Ohno demonstrated that manufacturing excellence is not achieved through increasingly complex processes, but through a relentless focus on what truly creates value.

In an era where industrial technology evolves faster than ever, his lesson remains surprisingly modern.

Innovation is not only about adding new capabilities.

It is also about having the discipline to remove everything that stands in the way of quality, efficiency and value.

In our next Touchpoints, we will explore how multimodal interaction is redefining industrial Human Machine Interfaces, enabling operators to communicate with increasingly intelligent systems through touch, voice, gestures and haptic feedback.