Harold Dodge said – “You cannot inspect quality into a product; it must be built into it.” This is something that has stuck with me ever since I entered the work force. This means that quality must be viewed as an intrinsic attribute of a manufacturing process. The idea of quality being part of the process cannot be brought out by talking to the employees or with slogans or short lived programs. In order to have quality be a part of the process, it has to be a part of the process intrinsically!
I came across the concept of James Watts’ centrifugal governor. This is essentially a feedback system that controls the speed of an engine at a desired state. This is shown in the picture above. As the speed increases, it causes the “flyballs” to move away from each other due to the centrifugal force and this cause the arms to go up, which controls the valve to reduce the fuel intake. This is beautifully explained by Stafford Beer in his 1966 book, “Decision and Control” . He states that with the centrifugal governor, the system is brought under control in the very act of going out of control. The regulation is intrinsic (it is part of the system).
When you think about it, Jidoka in TPS is doing exactly that. Jidoka is the governing principle in TPS to ensure built-in-quality. Jidoka was introduced as a concept by Sakichi Toyoda with his automatic loom that stopped when a thread was broken. Jidoka was explained by Toyota as autonomation or automation with human touch. In Toyota’s little green book, The Toyota Production System – Leaner Manufacturing for a Greener Planet, Jidoka is explained as;
Jidoka is a humanistic approach to configuring the human-machine interface. It liberates operators from the tyranny of the machine and leaves them free to concentrate on tasks that enable them to exercise skill and judgment.
Jidoka ensures that the machines are able to detect any abnormality and automatically stop whenever they occur. This concept of stopping production when there is an abnormality was implemented on the production lines with the use of andon cords. When an operator identifies a problem that cannot be solved within the allotted time, the operator can pull on the andon cord to stop the production line, thus making the problem immediately visible. This is a “human jidoka”. This prevents defective items from progressing down the assembly line causing larger issues and wasting time. It also leads to identifying opportunities for improvement with the product and/or the process as well as a valuable time to provide coaching for the employee.
The concept of Jidoka is an effort to make built-in-quality intrinsic to the manufacturing process. Allowing the operator to stop the entire production line is an act of giving autonomy to the operator. The quality is not being pushed top-down, but allowed to emerge bottom-up. This is an example of what Toyota calls as “Good Thinking leading to Good Products”.
In a similar vein, I wanted to draw comparisons to Zen. In Zen, there is a concept of “monkey mind”. This is the racing mind that does not allow one to sit down and meditate. Many different thoughts and emotions go through the mind when one is trying to have a quiet mind. Buddha taught disciples to focus on the breath as way to calm down the monkey mind. This is a really hard thing to do and requires a lot of practice. When the mind drifts off, it needs to be brought back. The Zen teachers teach us that the source of control is also the mind, the very same thing that causes the focus to be lost. Meditation is the art of coming back to the focus again and again. My favorite story on this is from the great teacher Yunmen Wenyan.
Yunmen was asked by his student, “How can I control my mind to not lose focus when I am trying to meditate?”
Yunmen replied, “The coin that is lost in the river can only be found in the same river.”
Always keep on learning…
In case you missed it, my last post was Learning to See: