ABSTRACT
A poka-yoke system possesses two functions: it can carry out 100 percent inspections and, if abnormalities occur, it can carry out immediate feedback and action. Poka-yoke systems fall into regulatory function categories, depending on their purposes, and setting function categories, according to techniques they use. Two regulatory functions are performed by poka-yoke systems: control methods and warning methods. The use of warning methods may be considered either where the impact of abnormalities is slight or where technical or economic factors make the adoption of control methods extremely difficult. The setting functions of poka-yoke systems can be divided into three categories: contact methods, fixed-value methods, and motionstep methods. With Fixed-Value methods, abnormalities are detected by checking for the specified number of motions in cases where operations must be repeated a predetermined number of times. Motion-Step Methods are methods in which abnormalities are detected by checking for errors in standard motions in cases where operations must be carried out with predetermined motions.
