Product Code Database
Autonomation describes a feature of machine design to effect the principle of 自働化（じどうか jidōka), used in the Toyota Production System (TPS) and lean manufacturing. It may be described as "intelligent automation" or "automation with a human touch".Toyota Production System, Taiichi Ohno, Productivity Press, 1988, page 6. This type of automation implements some supervisory functions rather than production functions. At Toyota, this usually means that if an abnormal situation arises, the machine stops and the worker will stop the production line. It is a quality control process that applies the following four principles: The Essence of Jidoka, Mark Rosenthal, SME Lean Directions Newsletter, 2002 Autonomation aims to:
The purpose of autonomation is that it makes possible the rapid or immediate address, identification and correction of mistakes that occur in a process. Autonomation relieves the worker of the need to continuously judge whether the operation of the machine is normal; their efforts are now only engaged when there is a problem alerted by the machine. As well as making the work more interesting this is a necessary step if the worker is to be asked later to supervise several machines. The first example of this at Toyota was the auto-activated loom of Sakichi Toyoda that automatically and immediately stopped the loom if the vertical or lateral threads broke or ran out.
For instance rather than waiting until the end of a production line to inspect a finished product, autonomation may be employed at early steps in the process to reduce the amount of work that is added to a defective product. A worker who is self-inspecting their own work, or source-inspecting the work produced immediately before their work station is encouraged to stop the line when a defect is found. This detection is the first step in Jidoka. A machine performing the same defect detection process is engaged in autonomation.
Once the line is stopped a supervisor or person designated to help correct problems gives immediate attention to the problem the worker or machine has discovered. To complete Jidoka, not only is the defect corrected in the product where discovered, but the process is evaluated and changed to remove the possibility of making the same mistake again. One solution to the problems can be to insert a "mistake-proofing" device somewhere in the production line. Such a device is known as poka-yoke.
For just-in-time (JIT) systems, it is absolutely vital to produce with zero defects, or else these defects can disrupt the production process – or the orderly flow of work.
JIT and Lean Manufacturing are always searching for targets for continuous improvement in its quest for quality improvements, finding and eliminating the causes of problems so they do not continually crop up.
Jidoka involves the automatic detection of errors or defects during production. When a defect is detected the halting of the production forces immediate attention to the problem.
The halting causes slowed production but it is believed that this helps to detect a problem earlier and avoids the spread of bad practices.JBLL, 18 June 2006
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