Image: Sample illustration
The Japanese term Poka Yoke (meaning “avoiding unfortunate mistakes”) can actually be defined simply as “avoiding mistakes”. The fundamental goal is a zero-error state. At the same time, however, it is recognized that no system and no human being is able to completely avoid unintentional errors. They are part of every production and process. Poka Yoke therefore attempts to reduce or completely avoid errors with mostly simple but effective systems and to reduce the impact of errors in the production process on the end product.
Shigeo Shingo is considered the inventor of the principle and the linguistic origin is derived from Go and Shogi (a Japanese variant of chess): In these, poka denotes a wrong move. In a broader sense, it means “stupid mistake, blunder”. Yoke comes from the verb yokeru, which means “to avoid”.
As Poka Yoke was developed as part of the Toyota Production System, it has its origins on the store floor. However, the principles also apply in the office, warehouse and service sector, as the examples below clearly show.
Processes in which fewer errors occur increase quality, but also have a significant impact on productivity. As the quality factor increases, the OEE naturally also increases. Throughput times can often be reduced with less rework and simpler processes. Of course, there are also cost factors.
The application of Poka Yoke is very simple: trace errors back to their sources and check how you can prevent the error from ever occurring again.
The six basic rules help with the application and can be guidelines for a suitable solution
Chamfer on a corner of a component to enable only one correct placement or connection (e.g. also SIM cards)
Staggered, asymmetrical placement of drill holes to create only one mounting option
Position sensors only allow a pressing process to start when the component is inserted correctly
Query of eye color in forms for customer service employees to ensure eye contact with the customer
