GENICHI TAGUCHI: BIOGRAPHY, CONTRIBUTIONS AND HIS CONCEPT OF QUALITY - DUDAS - 2025

Genichi Taguchi (1924-2012) was a Japanese engineer and statistician who developed a methodology based on statistics that allowed to improve the quality of manufactured products for the time. His ideas are considered industrial and business revolutionary.

He developed his studies and career in Japan, becoming a renowned character in the business world. His methods are known around the world; however, they are not applied on the same scale.

Genichi Taguchi's proposals met with great reluctance during their early years from the West. Over time, some industries have adapted to the Japanese methodology, while others continue to work under traditional methods.

The influence of its concepts on experimental and robust design, as well as the reduction in variations and some other of its postulates, have transcended the merely industrial and production conceptions to come to be applied in strictly commercial areas.

He was the author of numerous articles and books, and received many awards within and outside of his country. He was a member of the most important Japanese organizations for quality management: the Japanese Association for Quality Control and the Japanese Standard Association.

Biography

Taguchi was born in Tokamachi, a textile town belonging to Niigata prefecture. It is in this place where the future engineer grows up during his childhood. Due to the condition of the town, the Taguchi family was engaged in the manufacture and marketing of kimonos.

Years later this practice would lead Taguchi to study textile engineering at Kiryu University. Other sources claim that Genichi Taguchi graduated from this institution as a mechanical engineer.

Contrary to his wishes, Taguchi could not enter his family's local business because of the outbreak of World War II, which led the young engineer to the ranks and corridors of the astronomical department belonging to the Imperial Navy Institute of Navigation. Japanese.

Public charges

With the end of the Second World War, the then engineer Taguchi held his first public office: he joined the Ministry of Wealth and Public Health led by Motosaburo Masuyama, who was considered an eminence of statistics.

Masuyama encouraged Genichi Taguchi to experiment with statistics in certain industrial settings.

Taguchi's experimental work during these years progressed in parallel with his collaboration with the Institute of Statistical Mathematics.

1950s

Starting in the 1950s, Taguchi began to work in one of the largest telecommunications companies in his country, the Nippon Telegraph and Telephone Corporation (NTT), being appointed to the electrical communications laboratory.

Nippon Telegraph and Telephone Corporation. shibainu / CC BY (https://creativecommons.org/licenses/by/2.0)

During these years, companies began to implement statistical methods for quality control, so the engineer closely studied the potential of this resource.

Genichi Taguchi spent more than a decade working for this company, developing methods to improve the quality and reliability of different products. While this was happening, his company faced a clear rivalry with the American Bell Labs; both sought to develop the best technologies for quality control.

During this decade, Taguchi worked in conjunction with Asian companies and institutions, as well as individuals of North American and European origin. He obtained his doctorate in Statistical Sciences and Mathematics in 1962.

North America

Taguchi quit his job in the lab and took to traveling, visiting universities like Princeton and working as a consultant for fast-growing companies like Xerox, Boeing, Ford Motors, among others.

In North America, Taguchi collaborated with people whose companies were previously his rivals; This made it possible to strengthen cultural and knowledge ties.

Genichi Taguchi started his own private consulting agency, which he directed since 1982. He also devoted himself to teaching, being a professor at Japanese universities.

Most relevant contributions of Genichi Taguchi

Taguchi's main contributions revolved around statistics applied to industrial quality control and management processes, as well as measures that came to influence the administrative mechanisms of Japanese and Western companies.

The compendium of contributions developed and implemented by Genichi Taguchi is known as the Taguchi methods.

1- The loss function

L = K * (Y - M) ^ 2 is the equation of the Teguchi quality loss function.

Taguchi used to approach the production processes and the level of quality of a product through its stages, in order to have a better perception of the final product and its effect on the consumer.

The Japanese developed a mainly graphic descriptive scheme, through which he gave the loss an influential value for the rest of the production stages.

With this, Taguchi was able to make visible a phenomenon capable of affecting the quality of products, which responds to certain conditions that can be overcome by companies and workers.

Taguchi was able to determine the quality of a product based on the loss it generated to society throughout its useful life.

For a better understanding, Taguchi valued this degree of loss in numerical and money values, which gave the company a better idea of ​​its production grades and quality level.

The loss value implemented by Taguchi is never presented as a sudden phenomenon that will definitively affect the final quality of a product.

Its expression is in values ​​suitable for the different hierarchical levels of a production chain, which allows managers and workers to know the loss value of known products.

Through the loss function, Taguchi advocates variability in production. It leaves aside mechanical compliance with certain specifications and focuses on the target value of the final product.

2- Off-line quality control

Under this name, Taguchi developed a series of techniques that would allow the production process to be shielded, and thus minimize the variations that could result in a decrease in the quality of the final product. For all these processes, Taguchi developed and applied statistical tables.

The statistician conceived that the guarantee of a finished quality product is found in the design and manufacturing stages of the product itself.

Then he developed a series of components that would generate better production performance: system design, identification of parameters and determination of tolerance.

- System design

The design of the system consists simply in the conception of a product with the capacity to satisfy the needs of the user; that is functional, stable and of the highest possible value for its expected price in the market.

In this stage, methods are applied that determine consumer needs, which are then transformed into technical values ​​for their systematic application.

- Parameter identification

The parameter identification component is responsible for addressing all the variables involved in the process capable of influencing the final product, and the levels or parameters that will allow controlling the manifestation of these variables are established.

For this, Taguchi used experimental statistical designs, with which he had already worked much of his life.

- Determination of tolerance

The determination of tolerance is, as its name indicates, the assessment of the factors capable of affecting product variations and the tolerance levels that it will have within the conditions established for its production.

Not all variables are worked on, but only those that will provide greater efficiency in terms of the quality level of the product under certain conditions.

Taguchi was able to successfully isolate the most important variables during each stage, to work only with the most important ones.

3- Innovation in experimental design

Taguchi, who always worked with statistics and experimental functions, came to develop certain postulates for the application of industrial experiments in production areas, establishing some reasons to justify their use and maximize their effects.

Some of these postulates are related to determining design parameters to reduce performance disturbance to a minimum, reducing cost without affecting quality, identifying the influence of performance on value, and determining the characteristics of the product and identifying its levels of performance. tolerance.

Genichi Taguchi quality concept

Genichi Taguchi managed a philosophy of quality around certain principles that covered, as mentioned before, the entire production process until the arrival of the product at the hands of the final consumer.

Apart from what was proposed through the loss function, Taguchi advocated the continuous improvement of the quality of a product while reducing its production costs.

The Japanese believed that it was the only way a company could survive in a competitive economic environment.

Taguchi always approached his perceptions and quantitative processes as a whole; therefore, the quality and cost of a product are always accompanied by all the previous processes to which it was subjected during its production, along with the performance it has once it is in the hands of the consumer.

The continuous improvement of quality in the manufacture of a product must be, for Taguchi, an internal philosophy of great importance in the business environment. The neglect of a single gear is enough to lower the quality of a product.

References

1. Genichi Taguchi, SC (2005). Taguchi's Quality Engineering Handbook.
2. Roy, RK (2010). A Primer on the Taguchi Method, Second Edition. Michigan: Society of Manufacturing Engineers.
3. Taguchi, G. (1986). Introduction to quality engineering: designing quality into products and processes.
4. Taguchi, G., & Phadke, MS (1984). Quality Engineering through Design Optimization. In G. Taguchi, & MS Phadke, Quality Control, Robust Design, and the Taguchi Method (pp. 77-96).