Question: Potentiometers. Chamdani, Davis, and Kusumaptra worked with personnel from a potentiometer assembly plant to improve the quality of finished trimming potentiometers. The 14 wire springs fastened to the potentiometer rotor assemblies (produced elsewhere) were causing short circuits and open circuits in the final potentiometers. Engineers suspected that the primary cause of the problems was a lack of symmetry on metal strips holding these springs. Of concern were the distance from one edge of the metal strip to the first spring and the corresponding distance from the last spring to the other end of the strip.
(a) Suggest how the assembly plant might have discovered the short and open circuits.
(b) Suggest how the plant producing the rotor assemblies perhaps became aware of the short and open circuits (the production plant does not test every rotor assembly). (Hint: Think about one of the three important emphases of modern quality philosophy. How does your response relate to the six-step cycle in Table?)
(c) If "lack of symmetry" is the cause of quality problems, what should henceforth be recorded for each metal strip inspected?
(d) Based on your answer to (c), what measurement value corresponds to perfect symmetry?
