Poka-Yoke Method Yields Better Products, Services

Poka-yoke (PO-ka yo-KAY) is a Japanese term that means to “avoid unexpected surprises” or “avoid blunders.” As explained by TechTarget, when applied to product development, a poka-yoke is a safeguard that prevents a project or product from proceeding to the next step until the proper conditions have been met. This approach has long been used in the manufacturing industry as part of lean principles to ensure quality. It was popularized and developed in the late 1960s by Dr. Shigeo Shingo, an industrial engineer at Toyota.

No one likes making mistakes, be it at work or at home. The poka-yoke design approach is a methodology that helps prevent mistakes from happening in the first place. An example of this in consumer product design would be a microwave oven that incorporates three microswitches and latches in the door to ensure the door is closed before starting. This process eliminates the possibility of causing damage or injury from harmful microwaves without the protection built into the door. Another classic poka-yoke example is the electrical plug with an earth pin that is longer than the other pins and oriented so that it can only be inserted one way, ensuring safer electrical operation of an appliance.

At FTI, we apply this methodology to our product design processes. Our design process leverages six stage gates to ensure that all the required steps are completed and, more importantly, allow any errors to be identified and corrected before proceeding to the next phase. An organization which incorporates poka-yoke can protect profits, lower the risk of injury and increase the probability of meeting customer time and quality expectations.

In our design process, a poka-yoke step would be to identify long lead-time parts and get them ordered well ahead of the time needed. During the preliminary design review, the parts that have long lead times should be determined. Once the review has been completed, these parts can be submitted to purchasing for ordering. However, it is understood that some of these parts may never be used if design requirements and design implementations change. However, this poka-yoke can be considered an acceptable risk compared to having a design ready for production and awaiting receipt of parts ordered too late.

Our teams use poka-yoke both proactively and reactively, introducing an intervention device or process to catch mistakes before they are translated into nonconforming products. When setting up an operation or making changes, poka-yoke can identify points in the system where errors are most likely to occur. FTI engineers can then eliminate those steps and replace them with less error-prone ones. Or, if they cannot replace the steps, teams create ways to minimize the risk of them happening in the first place.

Is your organization utilizing poka-yoke methods to avoid errors? Implementation of quality methods like this can enable you to provide better products and services and place you ahead of your competition.