Techniques for measuring error motions of a precise rotational stage

Rotating stages in semiconductor industry, biotechnology and many other fields require challenging accuracy to perform their functions properly. To evaluate and improve the performance of such precision machinery, it is inevitable to consider the error motion on which knowledge can be used for error compensation, error-reducing design, and other improvement activity. In this study we have measured the 5 DOF error motions of a rotating stage with capacitive sensors. To achieve the measurement accuracy, we have used Donaldson's reversal, Estler's reversal, and other techniques. We have designed a sensor jig to achieve measurement including reversals effectively.