John G. Weenig
Jidoka
Engineering Quality
into our Processes
Objectives
• Learn about jidoka
• What techniques from jidoka could help us
improve our operations?
• Does jidoka have application for processes
other than manufacturing?
Material Covered
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Meaning of jidoka
Origins of jidoka
How jidoka works
Jidoka and the Toyota Production System
Using jidoka
Finding more on jidoka
Jidoka
Jidoka – A Japanese term made of three kanji
characters:
Ji – self
Do – movement, motion
Ka – -ize, to be or become
Jidoka
• Jidoka literally means: automation or
autonomation
• Jidoka: A quality control method that involves
thorough, automatic inspection of every product as
it moves through the conversion process.
• Ninbennoaru jidoka
• Taiichi Ohno
• Pursuit of Waste Elimination
Major Benefits
• Quality assurance
• Cost reduction
• Employee fulfillment
– lower turnover rate
– Improved productivity
• Continuous process improvements
What is Jidoka for?
• Jidoka makes any production problems selfevident by stopping production whenever
problems occur.
• Accompanies JIT or lean manufacturing
• Continuous improvement - Kaizen
• Why? Expose the truth
• Find the problems, bring them forth, and fix
them
• Do it once & once and for all
A metaphor
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Completion homework in school
What kind of behavior did that encourage?
Everyone tries to do homework
Yoda “Do or do not, there is no try”
That is Jidoka
Only good quality homework is received by the
teacher and poor work is unacceptable
• Preventing defective work is paramount
How Toyota uses jidoka
• Two deployments:
– Human
– Machine
Human
• Andon – A cord that runs the length of the
production line that when pulled will stop
the entire production line.
Andon Board
Green light – Normal operation
Yellow light – Assistance needed
Red light – Line has been stopped
Andon Board at Denso
Employee Behavior
• Common defects, errors, and problems are
recorded on an easel near the work station
• Daily reviews by team leaders of what
problems exist and their solutions
• Employees proactively seek solutions to
unresolved problems
Machine
• Poka-yoke: Machines are set-up to prevent
defects before they can occur.
– Examples
– Automobile cabin lights turn off when left on
too long
– Washing machines won’t run if the lid is left
open
Wastes Eliminated:
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Rework
Scrap
Waste in movement
Overproduction
Excessive waiting
How it used to work
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A defect is detected by a line worker
Rationalization
Rework or dissatisfaction
Status Quo – Problem might reoccur
Under Jidoka
• A defect is detected
• A line worker pulls the andon cord, which
summons a team leader
• A team leader and worker identify causes
• Solutions implemented
• Cost of line stoppage incurred, but it
incentivizes us to improve
Toyota Production System (TPS)
• At Toyota’s Georgetown, KY Plant…
Workstation
0%
70%
100%
Toyota at Georgetown
Andon cord area
Floor markings
Let’s try it
• Music begins to play and a light on the andon
board begins to flash yellow. What does this
mean?
• What happens if the team leader pulls the andon
cord after a first pull?
• What happens if a solution to a problem cannot be
found?
• Is jidoka a proactive or reactive approach to
continuous improvement?
Summary
• Jidoka: Makes any production problems
self-evident by stopping production
whenever problems occur.
• Put Toyota on the map
• Bedfellow of lean manufacturing &
continuous improvements
• It is organizational learning at its best
Sources and additional readings
Foster, S.T., Managing Quality, Pearson Prentice Hall, NJ, 2007
Miltenburg, John, One-piece flow manufacturing on U-shaped production lines: A tutorial.,IIE Transactions, Vol.33 Issue 4,
p303, April 2001.
Mishina, Kazuhiro; Takeda, Kazunori, Toyota Motor Manufacturing, U.S.A., Inc., President and Fellows of Harvard
College © 1992.
Monden, Yauhiro, Toyota Production System, Georgia: Institute of Industrial Engineers. 1983.
Young, Mark S., A Framework for Successful Adoption and Performance of Japanese Manufacturing Practices in the United
States, The Academy of Management Review © 1992.
Flynn, Barbara B.; Sakakibara, Sadao; Schroeder, Roger G., Relationship between JIT and TQM: Practices and
Performance, The Academy of Management Journal © 1995.
Toyota’s Official website: www.toyota.co.jp/en/vision/production_system/jidoka.html Accessed:03/24/2007