Taiichi Ohno (1912 – 1990)

Taiichi Ohno is considered the ‘Father of the Toyota Production System’ (TPS). In developing TPS, Ohno expanded upon and operationalized manufacturing ideas espoused by prior quality and operations management gurus, such as Edwards Deming and Joseph Juran. TPS transformed post WWII Japan into a dominant worldwide leader in manufacturing. TPS also inspired the hugely popular Lean’ production system, used extensively around the world (outside of Toyota and Japan). As articulated in his seminal book, Toyota Production System Beyond Large Scale Production (published in Japanese in 1978 and later translated into English in 1988), Ohno believed that making a factory function was akin to how a human body works.  The autonomic nervous system responds when asleep and functions in good health when correctly cared for, fed, watered, exercised frequently, and treated respectfully. Ohno’s transformational contributions to quality, manufacturing, and operations management (OM) make him an OM guru.

Taiichi Ohno was born in Dalian, China, in 1912 and spent much of his life in Japan, working as an engineer for the Toyota Motor Company. Ohno’s ideas and approach to manufacturing was based on simplicity, efficiency, and a relentless focus on eliminating waste. He believed that every step in the production process should add value to the final product, and he was constantly searching for ways to streamline operations. Ohno extensively observed operational efficiencies. He would spend hours on the factory floor, observing the processes and looking for improvement opportunities. He encouraged workers to take ownership of their jobs, be creative, and always look for improvement.

Ohno’s is credited with developing the Kanban system, a visual method for managing production that allows workers to see what needs to be done quickly and when. He also helped popularize the idea of “Just-in-time” (JIT) manufacturing, which involves producing goods only when needed rather than building up extensive inventories. Ohno’s impact on the automotive industry and manufacturing cannot be overstated. His ideas have been widely adopted worldwide, and his legacy inspires new generations of engineers and innovators. In 2022, Taiichi Ohno was posthumously inducted into the Automotive Hall of Fame.

Toyota Production System (TPS)

The Toyota Production System (TPS) is a manufacturing philosophy and management system developed by the Toyota Motor Corporation to improve efficiency, quality, and flexibility in production processes. It is a comprehensive system that involves all aspects of production, from design and engineering to production and delivery. TPS has two main pillars and eleven support elements which are collectively known as the ‘thirteen pillars of the Toyota Production System’. The two main pillars include:

• Just-in-time (JIT) production involves producing only what is needed, when it is needed, and in the required quantity. This helps to minimize waste and reduce inventory costs.
• Jidoka is a quality control process that stops production when a problem occurs. This facilitates immediate corrective action and helps prevent defects from being passed to the next stage of production.

The eleven support elements include:

1. Konnyaku Stone is a baseball-sized tool made of resins known as the ‘devil’s tongue, which removes imperfections by smoothing and preparing unpainted body panels for paint.
2. Poka-yoke is a mistake-proofing system that helps prevent defects. It involves designing processes and tools so that mistakes are impossible or difficult to occur.
3. Hansei is the process of recognizing and learning from mistakes to avoid them in the future. Hansei-kan meetings are held to discuss production failures and possible solutions.
4. Andon is a system of signals used to communicate production status and problems. This facilitates quick communication and decision-making, and immediate problem resolution.
5. Heijunka is a production leveling system that helps balance production and demand. This reduces fluctuations in production and demand and ensures that resources are used efficiently.
6. Kaizen is a continuous improvement process that makes incremental improvements to the production process.
7. Genchi Genbutsu is the concept that the best way to solve a problem is to observe and see it for yourself. Managers do this via “Genba (or Gemba) walks.”
8. Nemawashi is the idea that decisions should not be dictated by management but made as a team. Information is shared openly with employees who are involved in decision-making.
9. Kanban is a visual scheduling system that ensures the right parts and materials are available at the right time. This helps reduce inventory and lead times and improve production efficiency.
10. Muda (waste), Muri (overburden), and Mura (unevenness/variation) are the underlying wastes or inefficiencies within manufacturing and operational systems.
11. Genba is the physical place of work, and the underlying philosophy is that all actions and operations are transparent and can be seen with a visual inspection.

Seven Types of Waste

A key element of the TPS is the relentless pursuit of waste elimination. ‘Waste’ in this context is defined as anything within a production system that does not directly add value to the customer. Taiichi Ohno identified seven types of waste, also known as the “Seven Muda”, which follow the acronym TIMWOOD (with the acronym representing the first letter of each waste). These include:

1. Transportation: Unnecessary movement of materials or products, leading to increased cost and possible damage or loss.
2. Inventory: Excess inventory that ties up capital and resources can lead to obsolescence or waste.
3. Motion: Unnecessary or excessive movement of people or equipment, leading to increased cost and decreased efficiency.
4. Waiting: Time spent waiting for materials, equipment, or information, leading to decreased efficiency and increased lead time.
5. Overproduction: Producing more than needed or the customer demands, leading to excess inventory, transportation, and storage costs.
6. Over-processing: Unnecessary steps or over-processing of materials or products, leading to increased cost and decreased efficiency.
7. Defects: Products or materials that do not meet quality standards or customer requirements, leading to rework, scrap, or customer dissatisfaction.

An 8th waste was introduced in the 1990s – ‘Skills’, defined as wasting human potential, talent, creativity, and ideation. This created a new acronym, TIMWOODS.

Kaizen

Kaizen is a concept that emphasizes continuous improvement in all aspects of life. Taiichi Ohno was a strong advocate of kaizen in the workplace, believing that minor, incremental improvements made over time could significantly improve productivity, quality, and efficiency. Ohno called these improvements “kaizen events” and encouraged his workers to participate actively. At the heart of Ohno’s kaizen approach was the idea of “muda”, discussed previously. Ohno believed that by eliminating muda through kaizen events, Toyota could streamline its operations and increase efficiency.

Ohno developed several tools and techniques to eliminate muda. These include the Kanban system, which helps to control inventory and reduce waste; the Andon system, which alerts workers to problems in the production process; and the 5S system (Seiri [Sort], Seiton [Set in order], Seiso [Shine], Seiketsu (Standardize], and Shitsuke [Sustain]), which focuses on workplace efficiency, effectiveness, and safety.

The Big Ideas for Operations Management

The TPS transformed Japan into a manufacturing world superpower during the 1970’s and 1980’s and spurred the development of Just-In-Time and subsequently, Lean Production. Lean is still considered a best-in-class approach to production used throughout the world today. As part of developing and implementing the TPS, Ohno participated in developing several concepts, ideas, and techniques designed to improve the effectiveness and efficiency of production systems. These include the ‘seven wastes’, kaizen, visual management, kanban, andon, and 5S. Ohno’s ideas have profoundly impacted all aspects of operations, in manufacturing and service industries, and inspired countless organizations around the world to adopt the principles and practices.

Sources

AHOF. (2022). Taiichi Ohno. Automotive Hall of Fame. https://www.automotivehalloffame.org/honoree/taiichi-ohno/

Kanban Zone. (2023). Toyota Production System. Kanban Zone. https://kanbanzone.com/resources/lean/toyota-production-system/

Kemp, A. (2018, March). Taiichi Ohno: Hero of the Toyota Production System. QAD Blog. https://www.qad.com/blog/2018/03/taiichi-ohno-toyota-production-system

Naydenov, P. (2019, November). Kaizen: Lost in Translation. Kanbanize. https://kanbanize.com/blog/kaizen-continuous-improvement/

Ohno, T. (1988). Toyota Production System: Beyond Large-Scale Production. Productivity Press.

Shingo, S., & Dillon, A. P. (1989). A study of the Toyota production system: From an Industrial Engineering Viewpoint. CRC Press.

Skhmot, N. (2017, August). The 8 Wastes of Lean. The Lean Way. https://theleanway.net/The-8-Wastes-of-Lean#:~:text=The original seven wastes (Muda,by the acronym “TIMWOOD”.

Toyota Blog. (2014, April). 13 pillars of the Toyota Production System. Toyota UK Magazine. https://mag.toyota.co.uk/13-pillars-of-the-toyota-production-system/

Toyota Company. (2023). Toyota Production System. Toyota Company. https://global.toyota/en/company/vision-and-philosophy/production-system/

Toyota Newsroom. (2022). 2022 Automotive Hall of Fame Inducts Taiichi Ohno, ‘Father of TPS.’ Toyota Newsroom. https://pressroom.toyota.com/2022-automotive-hall-of-fame-inducts-taiichi-ohno-father-of-tps/